The Dinosaur Field Guide Supplement

Transcription

1 The Dinosaur Field Guide Supplement September 2010 December 2014 By, Zachary Perry (ZoPteryx) 1

2 Disclaimer: This supplement is intended to be a companion for Gregory S. Paul s impressive work The Princeton Field Guide to Dinosaurs, and as such, exhibits some similarities in format, text, and taxonomy. This was done solely for reasons of aesthetics and consistency between his book and this supplement. The text and art are not necessarily reflections of the ideals and/or theories of Gregory S. Paul. The author of this supplement was limited to using information that was freely available from public sources, and so more information may be known about a given species then is written or illustrated here. Should this information become freely available, it will be included in future supplements. For genera that have been split from preexisting genera, or when new information about a genus has been discovered, only minimal text is included along with the page number of the corresponding entry in The Princeton Field Guide to Dinosaurs. Genera described solely from inadequate remains (teeth, claws, bone fragments, etc.) are not included, unless the remains are highly distinct and cannot clearly be placed into any other known genera; this includes some genera that were not included in Gregory S. Paul s work, despite being discovered prior to its publication. All artists are given full credit for their work in the form of their last name, or lacking this, their username, below their work. Modifications have been made to some skeletal restorations for aesthetic reasons, but none affecting the skeleton itself. Should any artist want their piece modified or removed from this supplement, they may contact the author. All life restorations are by the author and based on the accompanying skeletal diagram. All artwork corresponds to the entry immediately above it. The author apologizes in advance for any typos, overlooked information, and inconsistencies that may be present in this and future supplements. 2

3 Baso-Dinosaurs Dinosaurs Nyasasaurus parringtoni 2.4 m (8 ft) TL, 15 kg (30 lb) Fossil Remains: Partial skeleton. Anatomical Characteristics: Three sacral vertebrae; neck vertebrae elongated, hollow, possibly pitted as in theropods; long deltopectoral crest on humerus. Age: Middle Triassic, Anisian. Distribution: Tanzania; Manda Formation. Habits: Growth apparently more rapid than herrerasaurs. Was likely omnivorous and capable of running faster than most contemporary animals. Notes: Tentatively placed within dinosauria. May be a common ancestor of both ornithischia and saurischia, although some analyses have concluded that it is most likely a theropod. If it is not a dinosaur, then it is the most derived protodinosaur yet known. First remains mistakenly placed in much later Thecodontosaurus. It is not certain that the two known specimens belong under the same genus or species. Theropods Herrerasaurs Sanjuansaurus gordilloi 2.5 m (9 ft) TL, 30 kg (60 lb) Fossil Remains: Minority of skull and partial skeleton. Anatomical Characteristics: Standard for baso-theropods. Age: Late Triassic, Carnian. Distribution: Northern Argentina; Ischigualasto. Habitat: Seasonally well-watered forests, including dense stands of giant conifers. Habits: Generalist predator. Notes: Prey included Pisanosaurus, Panphagia, and Eoraptor. Main enemies Herrerasaurus and large thecodonts. Alcober & Martinez 3

4 ZP Derived Non-Avepods Eodromaeus murphi 1.2 m (4 ft) TL, 5 kg (10 lb) Fossil Remains: Majority of skull and skeleton. Anatomical Characteristics: Relatively standard for baso-therapods, but overall more gracile and with a less robust pubis than herrerasaurs. Age: Late Triassic, Early Carnian. Distribution: Northern Argentina; Ischigualasto. Habitat: Seasonally well-watered forest, including dense stands of giant conifers. Habits: Hunted small game. Notes: More advanced than typical herrerasaurs but less advanced than avepods. Shared its habitat with similar sized Eoraptor and larger Herrerasaurus, was likely prey of the latter. Prey included Panphagia and Pisanosaurus. Sereno & Abraczinskas 4

5 ZP Avepods Daemonosaurus chauliodus 1.5 m (5 ft) TL, 5 kg (10 lb) Fossil Remains: Complete skull and minority of skeleton. Anatomical Characteristics: Snout short and sloping. Eyes large. Teeth in upper jaw elongated. Upper jaw indented near tip and slightly longer than lower jaw. Teeth at front of upper and lower jaws are procumbent. Age: Late Triassic, Rhaetian. Distribution: New Mexico; Chinle. Habitat: Well-watered forest. Habits: Probably preyed on small game. Notes: More advanced than herrerasaurs, but may or may not be avepods. Shared its habitat with Coelophysis, Chindesaurus, and Tawa. Sues et al. ZP Tawa hallae 2.2 m (7 ft) TL, 13 kg (30 lb) Fossil Remains: Complete skull and several skeletons, juvenile to adult. Anatomical Characteristics: Overall build very similar to coelophysoids, but arms longer. Pelvis short like herrerasaurs. Age: Late Triassic, Early Norian. Distribution: New Mexico; Chinle. Habitat: Well-watered forests, including dense stands of giant conifers. Habits: Capable of hunting small and medium game. Skeletons of various ages found together may suggest some sort of group behavior. 5

6 Notes: Likely competed with Coelophysis and Chindesaurus. Enemies included large thecodonts. More advanced than herrerasaurs, but less advanced than coelophysoids; may or may not be avepods. Hartman Tachiraptor admirabilis 1.5 m (5 ft) TL, 5 kg (10 lb) Fossil Remains: Minority of skeleton. Age: Early Jurassic, Hettangian. Distribution: Venezuela; La Quinta. Notes: Potential prey included Laquintasaura. Coelophysoids Panguraptor (or Coelophysis) lufengensis 1.5 m (5 ft) TL, 5 kg (10 lb) Fossil Remains: Majority of skull and partial skeleton. Anatomical Characteristics: Snout and arms relatively short. Age: Early Jurassic, Hettangian. Distribution: Southern China; lower Lufeng. ZP 6

7 Notes: More closely related to Coelophysis than to Syntarsus, suggesting that all should either be lumped into Coelophysis, or Syntarsus should be elevated back to the genus level. Main enemy Sinosaurus, potential prey included early mammals and young prosauropods. Studziński Zupaysaurus rougieri See 75 Notes: Recent research indicates that Zupaysaurus s large crests may actually be displaced lacrimal bone. Sinosaurus triassicus See 76 Notes: Dilophosaurus sinensis has been found to be a junior synonym of this genus and species. Abelisauroids Baso-Abelisauroids ZP 7

8 Fosterovenator churei Fossil Remains: Minority of skeleton. Age: Late Jurassic, Middle Tithonian. Distribution: Wyoming; upper Morrison. Habitat: Semiarid with open floodplain prairies and riverine forests. Notes: Classification uncertain, probably the first known basal abelisauroid from the northern hemisphere. May include remains assigned to Elaphrosaurus? unnamed species. Shared its habitat with the much larger Allosaurus and Torvosaurus, amongst many other dinosaurs. Dahalokely tokana 3.5 m (12 ft) TL, 40 kg (85 lb) Fossil Remains: Minority of skeleton. Anatomical Characteristics: Robustly constructed. Age: Late Cretaceous, Turonian. Distribution: Madagascar; Diego Basin. Notes: Taxonomic placement uncertain due to incompleteness of remains. May be a large basal noasaurid, as some evidence suggests, or a small abelisaurid. At the time of Dahalokely s existence, Madagascar and India were linked together as a large island. Abelisaurids Eoabelisaurus mefi 6 m (20 ft) TL, 750 kg (1,600 lb) Fossil Remains: Partial skull and majority of skeleton. Anatomical Characteristics: Skull tall and arms shortened, but still functional. Vertebral spines over hips and base of tail form shallow ridge. Age: Middle Jurassic, Late Aalenian or Early Bajocian. Distribution: Southern Argentina; Cañadón Asfalto. Notes: Oldest known abelisaurid. Shared its habitat with Piatnitzkysaurus, Condorraptor, and a variety of sauropods. Rauhut 8

9 Kryptops palios See 78 Notes: Portions of skeleton may belong to Eocarcharia. Pycnonemosaurus nevesi See 79 Notes: Correct spelling of Pycnoneosaurus. ZP Majungasaurus crenatissimus See 80 Anatomical Characteristics: Neck robust and fairly long, shorter legs result in a low-slung appearance. Hartman Rahiolisaurus gujaratensis 7.5 m (25 ft) TL, 2 tonnes Fossil Remains: Minority of several skeletons found in association. Anatomical Characteristics: Leg long and gracile. Age: Late Cretaceous, Maastrichtian. Distribution: Western India; Lameta. Habits: Hunted titanosaur sauropods and ankylosaurs. Notes: May be the same as contemporary Indosuchus raptorius. Shared its habitat with Rajasaurus. Vitakridrinda sulaimani 7.5 m (25 ft) TL, 2 tonnes Fossil Remains: Minority of skull and skeleton. 9

10 Age: Late Cretaceous, Maastrichtian. Distribution: Pakistan; Pab. Notes: Appears fairly standard for an abelisaurid, but too little known to be certain. Arcovenator escotae 6 m (20 ft) TL, 750 kg (1,600 lb) Fossil Remains: Minority of skull and skeleton. Anatomical Characteristics: Bony brow ridges well developed. Age: Late Cretaceous, Late Campanian. Distribution: France; Lower Argiles Rutilantes. Habitat: Large subtropical island with large rivers. Notes: Potential prey included titanosaurs and rhabdodonts. Noasaurids Velocisaurus unicus 1.5 m (5 ft) TL, 15 kg (30 lb) Fossil Remains: Minority of skeleton. Anatomical Characteristics: Middle toe enlarged, outer toe atrophied. Claws short and straight. Age: Late Cretaceous, Santonian. Distribution: Northern Argentina; Bajo de la Carpa. Habits: Peculiar foot anatomy, unlike any other known dinosaur, likely an adaptation for running. Notes: Prey may have included Alvarezsaurus and flightless birds. Shared its habitat with Bonitasaura. Averostrans Elaphrosaurs Ceratosaurs Genyodectes serus Fossil Remains: Minority of skull. Anatomical Characteristics: Snout robust, teeth long and dagger-like. Age: Early Cretaceous, Aptian. Distribution: Southern Argentina; Cerro Barcino. Notes: Classification uncertain, but arrangement of teeth most like that of Ceratosaurus. Shared its habitat with Tyrannotitan and Chubutisaurus. Camarillasaurus cirugedae 3 m (10 ft) TL, 70 kg (150 lb) Fossil Remains: Minority of skeleton. Age: Early Cretaceous, Early Barremian. Distribution: Spain; Camarillas. 10

11 Notes: The only Cretaceous age non-abelisauroid ceratosaur known from Eurasia thus far. Prey included hypsilophodonts and iguanodonts. Exact classification uncertain, may be an elaphrosaur. Tetanurans Baso-Tetanurans Kayentavenator elysiae Fossil Remains: Minority of skeleton, juvenile. Age: Early Jurassic, Pliensbachian. Distribution: Arizona; Kayenta. Habitat: Well-watered forest, likely surrounded by arid regions. Notes: May be one of the earliest tetanurans or an advanced coelophysoid. Shared its habitat with Dilophosaurus. Megalosaurs Cruxicheiros newmanorum 9 m (30 ft) TL, 2 tonnes Fossil Remains: Minority of skull and skeleton. Age: Middle Jurassic, Bathonian. Distribution: Central England; Chipping Norton Limestone. Notes: Originally placed in Megalosaurus. Taxonomic placement uncertain, may be a basal carnosaur. Leshansaurus qianweiensis 7 m (21 ft) TL, 700 kg (1,500 lb) Fossil Remains: Partial skull and skeleton. Anatomical Characteristics: Snout fairly wide toward front. Age: Middle to Late Jurassic, Bathonian to Callovian. Distribution: Central China; Dashanpu, Shangshaximiao. Habitat: Heavily forested. Habits: Potential prey included sauropods and stegosaurs. Purpose of widened snout unclear, may have allowed for a larger bite when attempting to wound large prey. Notes: Originally classified as a sinraptorid, is more likely a megalosaur. Snout shows some similarities to Afrovenator. Torvosaurus gurneyi 10 m (30 ft) TL, 3 tonnes Fossil Remains: Minority of skull and skeleton. Anatomical Characteristics: More robust and with fewer teeth than T. tanneri. Age: Late Jurassic, Late Kimmeridgian. Distribution: Portugal; Lourinhã. Habitat: Large seasonally dry island with open woodlands. Habits: Big game hunter, potential prey included sauropods and stegosaurs. 11

12 Notes: Theropod eggs and embryos found in the region likely belong to this species. Sciurumimus albersdoerferi Fossil Remains: Nearly complete juvenile skull and skeleton, external fibers. Anatomical Characteristics: In juveniles: Snout subtriangular. Tail fairly long. Simple protofeathers cover much of body, particularly long over base of tail. Age: Late Jurassic, Early Tithonian. Distribution: Southern Germany; Painten. Habitat: Semi-arid islands. Habits: Likely hunted small game. Adults diet unknown. Notes: The first non-coelurosaur found with definitive feathers. It is unknown if these feathers were retained into maturity. Although superficially similar to Juravenator starki, the two appear to be quite distinct from one another. Not all researchers agree that Sciurumimus is a megalosauroid, preferring to classify it as a very basal coelurosaur. As physical features can change with maturity, any exact classification is tentative. Skeletal shown here is only partially restored. ZP ZP 12

13 Spinosaurs Notes: Fragmentary remains suggest presence in Australia. Other fragments suggest that derived spinosaurs may have existed as early as the Late Jurassic. Ichthyovenator laosensis 8.5 m (28 ft) TL, 1.7 tonnes Fossil Remains: Minority of skeleton. Anatomical Characteristics: Vertebral spines moderately long but show an abrupt decrease in height over hips, and then rise again over base of tail. This gap appears to be natural, but it is unclear if it would have been visible in life. Age: Early Cretaceous, Aptian. Distribution: Laos; Grès supérieurs. Habitat: Coastal river delta. Notes: The first definitive spinosaur from Asia. Probably includes Siamosaurus suteethorni, which is based on inadequate remains. Shared its habitat with sauropods and iguanodonts. Spinosaurus aegypticus See m (49 ft) TL, 10 tonnes Fossil Remains: Minority of skulls and partial skeletons, juvenile and adult. Anatomical Characteristics: Snout pitted with receptor sites, neck fairly long, hand rather long, tall (over 2 m tall) skin-covered sail over body, pelvis small, legs barely longer than arms. Toes bear flattened claws and the hallux is elongated and lowered, so feet likely webbed in life. Limb bones are quite dense internally. Habits: Spent most of its time in the water; either walking on the bottom when in the shallows or paddling with feet when in deeper water, paddling motion likely accompanied by horizontal undulation of the tail. Sensory pits on snout, like those of crocodilians, suggest that Spinosaurus was a tactile feeder of aquatic prey; probably either a sit-and-wait predator of passing game or moved slowly along feeling with snout akin to a stork. Though sail likely played a role in thermoregulation, greatly exaggerated size indicates a primary function of communication to other members of its species, perhaps allowing rivals to assess the size and strength of each other while the majority of the body was submerged. Far forward center of gravity and short legs imply that quadrupedal movement was employed on land, but this is not certain, and a slow bipedal gate is perhaps more likely. Notes: Current skeletal model is a composite of Egyptian and Moroccan material from specimens of varying maturity, thus it raises numerous concerns regarding reliability. Recent studies indicate the Moroccan material can safely be regarded as that of a spinosaur, most likely Spinosaurus, but no material overlaps the original Egyptian remains for comparison. Proposed quadrupedal movement on lands has received numerous criticisms as the theropod pectoral girdle and forelimbs are not designed to support weight or move in a fashion conducive to walking. Short hips and legs are scaled up from the remains of a Moroccan juvenile; as ontogenic changes in dinosaurs can be profound, it s possible that the hips and legs in a mature adult would have been proportioned more normally. 13

14 Ibrahim et al. Oxalaia (or Spinosaurus) quilombensis 14 m (45 ft) TL, 10 tonnes Fossil Remains: Minority of skull and skeleton. Age: Late Cretaceous, Early Cenomanian. Distribution: Eastern Brazil; Alcântara. Notes: Known from only a snout tip and a few other fragments. Avetheropods Baso-Avetheropods Carnosaurs ZP 14

15 Carnosaur Miscellanea Allosauroids Sinraptorids Allosaurids Allosaurus lucasi 10 m (30 ft) TL, 3 tonnes Fossil Remains: Partial skull and minority of skeleton, juvenile and adult. Anatomical Characteristics: Skull more robustly constructed then other Allosaurus species. Age: Late Jurassic, Tithonian. Distribution: Colorado; upper Morrison. Habitat: Semiarid with open floodplain prairies and riverine forests. Habits: Big game hunter. Notes: May include remains assigned to Allosaurus atrox. Lourinhanosaurus (or Allosaurus) antunesi See 96 Notes: Eggs with embryos found nearby likely belong to this species. Classification uncertain, may be a basal coelurosaur. Carcharodontosaurids Veterupristisaurus milneri Fossil Remains: Minority of skeleton. Age: Late Jurassic, Late Kimmeridgian/Early Tithonian. Distribution: Tanzania; middle Tendaguru. Habitat: Coastal, seasonally dry with heavier vegetation further inland. Notes: Fairly large in size. If this is a carcharodontosaurid, it is the earliest known. Aerosteon riocolloradensis See 99 Notes: Correct spelling of Aerosteons. Eocarcharia dinops See 97 Notes: A pelvis assigned to Kryptops may belong to this species. Becklespinax altispinax 7 m (23 ft) TL, 1 tonne Fossil Remains: A few vertebrae. Anatomical Characteristics: At least some vertebral spines relatively tall. Age: Early Cretaceous, Valanginian. 15

16 Distribution: Southeast England; Hastings Beds. Notes: Exact placement of tall spined vertebrae uncertain, initially thought to be above the shoulders but may actually be closer to the hips as in Concavenator. Taxonomic placement questionable, could be another type of allosauroid or even a spinosaurid. Shared its habitat with Hylaeosaurus and iguanodonts. Concavenator corcovatus 6 m (20 ft) TL, 500 kg (1,000 lb) Fossil Remains: Majority of skull and skeleton. Anatomical Characteristics: Vertebrae just before hips rise sharply to form a sail-like structure extending over hips and likely connecting to second smaller rise in vertebrae at base of tail. Alternatively, these may have formed separate hump-like structures. Bony knobs along back of ulna may be quill nodes. Age: Early Cretaceous, Barremian. Distribution: Spain; Calizas de al Huergina. Habitat: Well-watered forest and floodplains. Habits: Sail or hump almost certainly had a display function, but potential mechanical use is unclear. May have been used in thermoregulation and/or as a site for muscle attachments. Preyed included sauropods, iguanodonts, and Pelecanimimus. Notes: Bony knobs on ulna may actually be muscle attachment points, as their arrangement is not consistent with those of known quill nodes. Sinkkonen ZP 16

17 Sauroniops pachytholus 12 m (40 ft) TL, 6 tonnes Fossil Remains: Minority of skull. Anatomical Characteristics: Skull roof robust in structure. Age: Late Cretaceous, Early Cenomanian. Distribution: Morocco; Kem Kem Beds. Habitat: Coastal region with arid interior. Notes: Could potentially be a large abelisaurid, but carcharodontosaurid identity is more likely. Neovenatorids Notes: Subgroup megaraptora, which includes all members except Neovenator and Chilantaisaurus, may actually be basal coelurosaurs close to tyrannosauroids. All are left within neovenatorids at this time until the taxonomy of the group can be resolved. Megaraptor namunhuaiquii See 99 Fossil Remains: Minority of skeletons, adult. Majority of skull and skeleton, juvenile. Anatomical Characteristics: In large juveniles: Skull narrow and subtriangular, teeth relatively small. Arms well developed with slender hand claws, legs long and gracile. Habits: Likely a pursuit predator that used its teeth and claws to wound smaller prey. Notes: Juvenile remains suggest placement of this species and relatives within the tyrannosauroids. Until mature specimens can be found to test this theory, it has been left in its traditional position within neovenatorids. Get Away Trike! Blog 17

18 ZP Siats meekerorum Fossil Remains: Partial skeleton, large juvenile. Anatomical Characteristics: Fairly robust. Age: Early Creatceous, Early Cenomanian. Distribution: Utah; Upper Cedar Mountain. Habitat: Semiarid open woodland. Habits: Big game hunter. Notes: Establishes the presence of neovenatorids in North America and shows that they were capable of reaching the same sizes as carcharodontosaurids. Potential prey included nodosaurs, iguanodonts, and basal hadrosaurs. Datanglong guangxiensis 8 m (26 ft) TL, 1 tonne Fossil Remains: Minority of skeleton. Age: Early Cretaceous. Distribution: Eastern China; Xinlong. Notes: Originally classified as a basal allosauroid, is more likely neovenatorid or perhaps a basal tyrannosaur. Coelurosaurs Tyrannosauroids Baso-Tyrannosauroids Guanlong wucaii See 93 Notes: Almost certainly a tyrannosauroid related to Proceratosaurus and Kileskus. Proceratosaurus bradleyi 18

19 See 123 Notes: Most likely a basal tyrannosauroid close to Guanlong and Kileskus. Kileskus aristotocus 3 m (10 ft) TL, 70 kg (150 lb) Fossil Remains: Minority of skull and skeleton. Anatomical Characteristics: May have had a large midline crest. Age: Middle Jurassic, Bathonian. Distribution: Central Russia; Itat. Notes: Closest relative Proceratosaurus, and like it, probably a basal tyrannosauroid. Juratyrant langhami See 100 Notes: New genus for Stokesosaurus langhami. Yutyrannus huali 9 m (30 ft) TL, 2.5 tonnes Fossil Remains: Complete skull and nearly complete skeletons, external fibers, juvenile and adult. Anatomical Characteristics: Body standard for baso-tyrannosauroid. Low wavy midline crest on snout. Brow hornlets prominent. Arms well developed. Simple feathers up to 20 cm (8 inches) long covered most of body and limbs. Age: Early Cretaceous, Aptian. Distribution: Northeast China; Yixian. Habitat: Well-watered forests and lakes. Habits: Midline crest and brow hornlets were for display. Long feathers were likely for insulation in the cool Yixian climate. Two adults found together with a juvenile suggest this species may have lived in small family groups. Shows a standard tyrannosauroid growth pattern; limbs shorten and skull becomes more robust as age progresses. Notes: The largest dinosaur known to preserve direct evidence of feathers. The largest known predator in its habitat, prey included a variety of smaller therapods, ceratopsians, and ornithopods. Some features of the skull resemble those of allosauroids. Anton 19

20 ZP Hartman ZP Derived Tyrannosaurs Raptorex kriegstenis See 101 Notes: Found to be from younger sediments than the Yixian, most likely from the Nemegt. Also shown to most likely be a young juvenile, rather than a small adult. These factors combine to suggest that Raptorex is actually the juvenile of a larger tyrannosaur species, possibly Tarbosaurus. Tyrannosaurids Qianzhousaurus sinensis 9 m (30 ft) TL, 1 tonne Fossil Remains: Complete skull and partial skeleton. Anatomical Characteristics: Snout very long, low, and shallow. Crenulated midline crest on snout. Age: Late Cretaceous, Late Campanian. Distribution: Southeastern China; Nanxiong. Habits: Likely preferred smaller game, despite large size. Notes: Closely related to Alioramus, and with them likely represents a unique East Asian radiation of long-snouted tyrannosaurids. Some studies have found these long-snouted tyrannosaurs to be the sister group of true tyrannosaurids, rather than actually members. 20

21 Get Away Trike! Blog ZP Lythronax argestes 7.5 m (25 ft) TL, 2.5 tonnes Fossil Remains: Majority of skull and partial skeleton. Anatomical Characteristics: Skull short and stout. Body robust. Age: Late Cretaceous, Early Campanian. Distribution: Utah; Wahweap. Habits: Likely an ambush predator adapted to tackling robust game, such as ceratopsians. Notes: The earliest member of the lineage that would lead to Tyrannosaurus. Hartman ZP Teratophoneus curriei 7 m (23 ft) TL, 2 tonnes Fossil Remains: Partial skulls and skeletons. Anatomical Characteristics: Snout short and number of teeth reduced. Age: Late Cretaceous, Late Campanian. Distribution: Utah; Kaiparowits. Habitat: Riverine forests and floodplains. Habits: Short snout probably an adaptation for hunting well protected game, such as ceratopsians. Notes: Prey included Kritosaurus, Utahceratops, Kosmoceratops, and Hagryphus. Along with Bistahieversor, likely represents a unique lineage of tyrannosaurids in southwestern North America. 21

22 Hartman Zhuchengtyrannus magnus 9.5 m (31 ft) TL, 4 tonnes Fossil Remains: Partial skull. Anatomical Characteristics: Robustly constructed. Teeth bear extensive serrations. Age: Late Cretaceous, Campanian. Distribution: Eastern China; Wangshi Group. Notes: Prey included Sinoceratops, Zhuchengceratops, Tanius and Tsintaosaurus. Nanuqsaurus hoglundi 6 m (20 ft) TL, 1.5 tonnes Fossil Remains: Minority of skull. Age: Late Cretaceous, Late Maastrichtian. Distribution: Northern Alaska; Prince Creek. ZP 22

23 Habitat: Polar forest with warm humid summers and cold dark winters. Notes: Originally considered a species of Albertosaurus/Gorgosaurus, is instead more closely related to tyrannosaurines such as Tyrannosaurus. Potential prey included pachycephalosaurs, ceratopsians, and hadrosaurs. Ornithomimosaurs Baso-Ornithomimosaurs Hexing qingyi 1.1 m (3.5 ft) TL, 5 kg (12 lb) Fossil Remains: Complete skull and partial skeleton. Anatomical Characteristics: Snout narrow, tip of upper jaw curves downward. Tiny teeth restricted to front of jaws. Age: Early Cretaceous, Valanginian or Early Barremian. Distribution: Northeast China; lower Yixian. Habitat: Well-watered forests and lakes. Notes: The smallest known ornithomimosaur. Main enemy Sinornithosaurus. Jin et al. ZP Deinocheirus mirificus See m (36 ft) TL, 6 tonnes Fossil Remains: Complete skull and majority of skeletons, gastroliths. Anatomical Characteristics: Snout elongated, upper jaw shallow and terminates in a fairly broad squared-off beak, lower jaw very robust and terminates in a short cropping beak. Cheeks likely present along posterior half of jawline, no teeth present. Neck and arms are proportional normal for this large an ornithomimosaur, digits end in blunt hooked claws. Relatively narrow body is tilted upright by large hips and bears tall robust vertebral spines over midsection and hips, likely culminating in a camel-like hump in life. Legs relatively short, short toes end in blunt claws, hallux absent. Last few vertebrae of tail fused into a pygostyle, so likely supported a small feather fan. Habits: Small fish bones in stomach hint at an omnivorous lifestyle in and around swampy terrain. Hadrosaur-like beak, lack of teeth, robust lower jaw but weak bite force, and presence of many gastroliths suggest that the majority of this species diet was composed of soft low-growing plant matter with animal matter likely being taken opportunistically. Notes: Bizarre anatomy likely adaptations to supporting its supersized lifestyle, such as the wide beak to maximize eating efficiency and tall vertebral spines lined with stiffening ligaments that helped support the neck and stomach. Closest relatives appear to be Garudimimus and Beishanlong, together they form a sister-group to the ornithomimids. One skeleton shows evidence of being fed upon by Tarbosaurus. Evolution of a pygostyle may be independent of that of more advanced coelurosaurs. 23

24 Lee et al. ZP Lee et al. ZP 24

25 Lee et al. Ornithomimids Anserimimus planinychus See 113 Notes: Correct spelling of Ansermimus. Struthiomimus (or Ornithomimus) sedens See 117 Anatomical Characteristics: Short protofeathers found on neck, back, and legs; longer pennaceous feathers on lower arm of adults. Notes: Long arm feathers, only found in adults, appear ragged and most likely used for display. Qiupalong henanensis Fossil Remains: Partial skeleton. Anatomical Characteristics: Smaller than other derived ornithomimids. Age: Late Cretaceous, probably Campanian. Distribution: Central China; Qiupa. Notes: Closest relatives appear to be North American forms like Struthiomimus. Main enemy Luanchuanraptor. Maniraptors Compsognathids Juravenator starki See 118 Anatomical Characteristics: Small scales cover most of tail, legs, and snout. Simple protofeathers at base of tail and above hips, most likely covered more of body. Sinocalliopteryx gigas See 121 Habits: Known to have consumed smaller dinosaurs, including Sinornithosaurus and a small ornithischian, and the early bird Confuciusornis. Stomachs containing multiple prey items suggest that Sinocalliopteryx had a very high metabolism. Stomachs also found to contain small gastroliths. Maniraptor Miscellanea Bicentenaria argentina 3 m (10 ft) TL, 60 kg (130 lb) Fossil Remains: Majority of skull and partial skeleton. Numerous unevaluated remains. 25

26 Anatomical Characteristics: Snout subtriangular, hand short, legs long. Age: Late Cretaceous, Middle Turonian. Distribution: Western Argentina; Portezuelo. Habitat: Well-watered woodlands with short dry season. Habits: A pursuit predator of small- and medium-sized game. Notes: Little available information on this genus, despite apparent completeness of remains. Site locality contains a number of individuals that have yet to be excavated or thoroughly examined. May be a basal tyrannosauroid. Main enemy Megaraptor. Prey included Macrogryphosaurs and young titanosaurs. ZP Zuolong salleei 3 m (10 ft) TL, 70 kg (150 lb) Fossil Remains: Majority of skull and partial skeleton. Anatomical Characteristics: More robust than compsognathids, snout subtriangular. Age: Late Jurassic, Early Oxfordian. Distribution: Western China; Shishugou. Notes: Main enemy Yangchuanosaurus (=Sinraptor) dongi. ZP 26

27 Choiniere et al. ZP Aorun zhaoi Fossil Remains: Complete skull and partial skeleton, juvenile. Anatomical Characteristics: Head subtriangular. Thumb claw larger and more curved compared to other claws on hand. Age: Late Jurassic, Early Oxfordian. Distribution: Western China; Shishugou. Notes: Difficult to classify due to the immaturity of the specimen. A very basal coelurosaur, may not be a maniraptor, but it is seemingly more advanced than tyrannosauroids and possibly ornithomimosaurs. Main enemies included Sinraptor, Monolophosaurus, Guanlong, and Zuolong; it does not appear to be a juvenile of any of these. Scansoriopterygids Alvarezsaurs Alvarezsaurids Albinykus baatar 0.6 m (2 ft) TL, 1 kg (2 lb) 27

28 Fossil Remains: Complete legs and pelvis. Anatomical Characteristics: Bones in feet fused together. Age: Late Cretaceous, Santonian. Distribution: Mongolia; Javkhlant. Notes: Preserved in a sitting position reminiscent of modern birds. Alnashetri cerropoliciensis 1 m (3.3 ft) TL, 3.5 kg (8 lb) Fossil Remains: Minority of skeleton. Age: Late Cretaceous, Cenomanian. Distribution: Western Argentina; Candeleros. Habitat: Well-watered woodlands with short dry season. Notes: Main enemy Ekrixinatosaurus. Shared its habitat with Buitreraptor. Bonapartenykus ultimus 2.5 m (8 ft) TL, 25 kg (50 lb) Fossil Remains: Minority of skeleton, egg shell fragments. Age: Late Cretaceous, Late Campanian or Early Masstrichtian. Distribution: Western Argentina; Allen. Notes: Shared its habitat with Saltasaurus. Heptasteornis andrewsi Fossil Remains: Minority of skeleton. Age: Late Cretaceous, Maastrichtian. Distribution: Romania; Maastrichtian Sânpetru. Notes: Although the remains are very fragmentary, they are almost certainly those of a small alverezsaur, the first known from Europe. Linhenykus monodactylus 0.6 m (2 ft) TL, 1 kg (2 lb) Fossil Remains: Partial skeleton. Anatomical Characteristics: Completely lacked remnants of other fingers, neck relatively long. Age: Late Cretaceous, Early Campanian. Distribution: Northern China; Wulansuhai. Notes: Despite derived hands, this is still a relatively basal alvarezsaurid. 28

29 Xu et al. Xixianykus zhangi 0.4 m (1.3 ft) TL, 0.25 kg (0.5 lb) Fossil Remains: Partial skeleton. Anatomical Characteristics: Pubis strongly retroverted, foot strongly compressed from side to side. Age: Late Cretaceous, Campanian. Distribution: Eastern China; Majiacun. Notes: The oldest known derived alvarezsaurid. Avepectorans Deinonychosaurs Deinonychosaur miscellanea Pneumatoraptor fodori 0.7 m (2.5 ft) TL, 0.6 kg (1.3 lb) Fossil Remains: Minority of skeleton. Age: Late Cretaceous, Santonian. Distribution: Hungary; Csehbánya. Habits: Hunted small game. Notes: May be a dromaeosaurid or troodontid. Shared its habitat with Hungarosaurus. Anchiornis huxleyi See 128 Notes: Considered a primitive avian by some researchers. Xiaotingia zhengi 29

30 0.5 m (1.7 ft) TL, 0.5 kg (1.1 lb) Fossil Remains: Complete skull and majority of skeleton. Anatomical Characteristics: Overall very similar to Archaeopteryx, but arm and especially hand shorter. Teeth more robust. Hyperextendable toe well developed, but sickle claw not large. Age: Late Jurassic, Early Oxfordian. Distribution: Northeast China; probably Tiaojishan. Habits: Flight ability inferior to that of Archaeopteryx, if present at all. Diet included small game and possibly seeds. Notes: Originally thought to be an archaeopterygid, probably more closely related to Anchiornis. Exact origin of fossil unclear, slightly more derived deinonychosaur traits may lend toward the younger Yixian Formation. Considered a primitive avian by some researchers. Xu et al. 30

31 ZP Eosinopteryx brevipenna 0.3 m (1 ft) TL, 0.25 kg (0.5 lb) Fossil Remains: Complete skull and majority of skeleton, feathers. Anatomical Characteristics: Snout short, eyes large. Arms long, with well-developed symmetrical primary feathers; orientation of wing bones and shape of feathers made flapping flight improbable. Toes slender with unhooked claws, second toe not hyperextendable, hallux semireversed, and lower leg lacked feathers. Tail relatively short and may have lacked a pennaceous feather fan. Age: Late Jurassic, Oxfordian. Distribution: Northeast China; Tiaojishan. Habitat: Well-watered subtropical forest. Habits: Lack of feathers on feet and inability to flap indicates a more terrestrial existence than other small feathered deinonychosaurs of its age; legs and feet well suited for running. Likely a nocturnal predator of small game. Notes: Originally classified as a basal troodont, rather than a basal deinonychosaur. Lack of a feather fan at the end of its tail could be gender or age related, or a retained basal trait. Shared its habitat with Anchiornis, Xiaotingia, Aurornis, and Tianyulong. 31

32 Herran Pamparaptor micros 0.7 m (2 ft) TL, 1 kg (2 lb) Fossil Remains: Minority of skeleton. Anatomical Characteristics: Foot construction primitive. Age: Late Cretaceous, Turonian. Distribution: Southern Argentina; Portezuelo. Notes: Originally considered to be the same as Neuquenraptor. Exact classification uncertain, shows some similarities to troodontids. Balaur bondoc 2 m (6 ft) TL, 20 kg (40 lb) ZP 32

33 Fossil Remains: Partial skeleton. Anatomical Characteristics: Robustly constructed. Outer finger vestigial, claws on remaining fingers strongly hooked. Pubis highly retroverted. Hyperextendable hallux faces forward and bears sickle claw along with inner toe. Age: Late Cretaceous, Early Maastrichtian. Distribution: Romania; Sebeş. Habitat: Forested island. Habits: Robust legs, reduced hands, and retroverted pubis suggest that this species ate more plant matter than most other deinonychosaurs. Probably also an opportunist of small game. Notes: Originally thought to be velociraptorine dromaeosaurid, however, recent studies suggest that this is species is in fact a large and highly unusual member of a lineage closer to birds that also includes such species as Anchiornis and Xiaotingia. Unusual anatomy likely the result insular isolation. Archaeopterygids Ellison Aurornis xui 0.5 m (1.7 ft) TL, 0.5 kg (1.1 lb) Fossil Remains: Complete skull and skeleton, feathers. Anatomical Characteristics: Head subtriangular with highly pointed snout and small teeth. Neck relatively short. Body not deep. Pelvis short and pubis nearly vertical. Arm and hand very long, but unable to flap. Legs similar in length to forelimbs, ankles relatively short. Second toe not hyperextendable, hallux semireversed. Tail moderately long. Body covered in short feathers. Exact arrangement of symmetrical primary feathers uncertain, may have lacked feathers on feet and ankles. Age: Late Jurassic, Early Oxfordian. Distribution: Northeast China; Tiaojishan. Habits: Probably incapable of powered flight, some gliding possible. Fed on small game. Notes: Classification as basal archaeopterygid not certain. The most derived non-avian known, or the most primitive avian known, depending on the position of Archaeopteryx and other basal deinonychosaurs. Shared its habitat with Anchiornis, Xiaotingia, Eosinopteryx, and Tianyulong. 33

34 Herran ZP Dromaeosaurids Microraptorinae Sinornithosaurus millenii See 132 Anatomical Characteristics: Mottled coloration composed of rusty red, black, and gray. Notes: Despite popular claims, was not venomous. 34

35 Microraptor zhaoianus See 133 Anatomical Characteristics: First few teeth of lower jaw slightly procumbent. Two streamer-like feathers at end of tail. All feathers entirely glossy black, however, some individuals show color banding on primary feathers. Habits: Known to have preyed on small mammals, birds, and fish. Streamer feathers on tail and glossy coloration suggest that Microraptor may have been fairly social like many glossy black birds today, such as starlings, crows, and grackles. Differences in coloration amongst individuals likely represent sexual or age differences. Notes: Likely includes M. hanqingi. Changyuraptor yangi 1.2 m (4 ft) TL, 5 kg (10 lb) Fossil Remains: Complete skull and skeleton, feathers. Anatomical Characteristics: Tail long with long feathers (up to 30 cm) running its length. Long primary feathers on arms and legs extending onto feet. Age: Early Cretaceous, Early Aptian. Distribution: Northeast China; Yixian. Habitat: Well-watered forest and lakes. Habits: Small game hunter, able to attack larger prey than Microraptor. Aerial abilities likely inferior to those of Microraptor due to its larger size and long tail feathers. Notes: Possible descendent of Microraptor. Shared its habitat with a wide variety of other dinosaurs. Dromaeosaurid Miscellanea Dromaeosaurines Yurgovuchia doellingi 2.5 m (8 ft) TL, 25 kg (55 lb) Fossil Remains: Minority of skeleton. Age: Early Cretaceous, Barremian. Distribution: Utah; upper Cedar Mountain. Habitat: Short wet season, otherwise semiarid with floodplain prairies and open woodlands, and riverine forest. Notes: Shared its habitat with a variety of iguanodont, nodosaurs, basal therizinosaurs, and basal hadrosaurs. Main enemy Utahraptor. Velociraptorines Linheraptor (or Tsaagan) exquisitus 2 m (7 ft) TL, 15 kg (30 lb) Fossil Remains: Complete skull and majority of skeleton. Anatomical Characteristics: Very similar to Velociraptor, slightly more robust overall. Age: Late Cretaceous, Early Campanian. Distribution: Northern China; Wulansuhai. Habitat: Desert with dunes and oases. 35

36 Habits: Generalist predator. Notes: Apparently more closely related to Tsaagan than either is to Velociraptor. Shared its habitat with at least one of the raptors mentioned above, as well as Protoceratops, oviraptorids, and Saurornithoides. Headden Pyroraptor olympius 1.3 m (4 ft) TL, 5 kg (10 lb) Fossil Remains: Minority of skeleton. Age: Late Cretaceous, Late Campanian to Early Maastrichtian. Distribution: France; Grès à Reptiles. Notes: Shared its habitat with sauropods. Acheroraptor temertyorum 2.5 m (8 ft) TL, 25 kg (55 lb) Fossil Remains: Minority of skull. Anatomical Characteristics: Snout more robust than relatives. Age: Late Cretaceous, Late Maastrichtian. Distribution: Montana; Hell Creek. Habitat: Well-watered forests and floodplains. Notes: First velociraptorine known from North America. ZP 36

37 Unenlaginines Rahonavis ostromi See 138 Notes: Considered a primitive avian by some researchers. Troodonts Byronosaurus jafferi See 141 Notes: Hatchling skulls, originally assigned to Velociraptor, have been found oviraptorid nests. How this would come to be is uncertain, most likely the oviraptorid preyed upon the hatchling troodontids and fed them to its own young. It has been suggested, however, that Byronosaurus may have been a nest parasite, in which case the newly hatched troodontids may have preyed on their sibling oviraptorids. Xixiasaurus henanensis Fossil Remains: Partial skull. Anatomical Characteristics: Snout long and shallow. Age: Late Cretaceous, Campanian. Distribution: Eastern China; Majiacun. Habits: Preyed upon small game, possibly fished. Notes: Closely related to Byronosaurus. Together they probably represent a unique East Asian radiation of troodontids. Geminiraptor suarezarum 2 m (7 ft) TL, 20 kg (40 lb) Fossil Remains: Partial skull. Anatomical Characteristics: Snout not slender. Teeth robust. Age: Early Cretaceous, Early Barremian. Distribution: Utah; upper Cedar Mountain. Habitat: Short wet season, otherwise semiarid with floodplain prairies, open woodlands, and riverine forests. Notes: The oldest confirmed troodontid from North America. Shared its habitat with Eolambia, Hippodraco, and Iguanacolossus. Linhevenator (or Saurornithoides?) tani 2 m (7.5 ft) TL, 20 kg (40 lb) Fossil Remains: Partial skull and skeleton. Anatomical Characteristics: Arms short and robust. Sickle claw large. Age: Late Cretaceous, Campanian. Distribution: Northern China; Bayan Mandahu. Habitat: Desert with dunes and oases. Habits: Possibly hunted larger game than most troodontids. Notes: May be congeneric with Saurornithoides. Talos sampsoni 2 m (7 ft) TL, 15 kg (30 lb) 37

38 Fossil Remains: Partial skeleton. Age: Late Cretaceous, Campanian. Distribution: Utah; Kaiparowits. Notes: Potential prey included Kritosaurus and Hagryphus. Main enemy Teratophoneus. Hartman Gobivenator mongoliensis 1.6 m (5 ft) TL, 3 kg (7 lb) Fossil Remains: Complete skull and majority of skeleton. Anatomical Characteristics: Snout narrow, otherwise standard for large troodontid. Age: Late Cretaceous, late Campanian. Distribution: Mongolia; Djadochta. Habitat: Desert with dunes and oases. Habits: Small game hunter, possible took plant matter on occasion. Notes: The most complete large troodontid known. Potential prey included alvarezsaurs. Shared its habitat with Saurornithoides and velociraptorine dromaeosaurs. Tsuihiji et al. 38

39 ZP Oviraptorosaurs Ningyuansaurus wangi 1 m (3 ft) TL, 3 kg (7 lb) Fossil Remains: Partial skull and majority of skeleton, feathers. Anatomical Characteristics: Skull more elongated than other oviraptorosaurs, also with more teeth and a straighter lower jaw than usual. Body short and deep, pelvis not large. Arms and hands short, outer finger reduced. Legs very long, hallux semireversed. Tail long by oviraptorosaur standards. May have had a feather fan at the end of its tail. Age: Early Cretaceous, Early Aptian. Distribution: Northeast China; upper Yixian. Habitat: Well-watered forests and lakes. Habits: Known to have eaten seeds, so likely omnivorous. Main defense high speed. Notes: The most basal known oviraptorosaur, as favored by the long tail and relatively high number of teeth which are oriented like those of protarchaeopterygids. However, unlike protarchaeopterygids, it has long legs, short arms, and a long skull which are more similar to caudipterygids. Alternatively, it could be an indeterminate basal deinonychosaur. 39

40 Studziński ZP Omnivoropterygids 40

41 See 144 Notes: Most authorities consider omnivoropterygids to be birds distantly related to oviraptorosaurs. Protarchaeopterygids Epidexipterygids Notes: Despite similarities in skull construction, these are almost certainly scansoriopterygids. Caudipterygids Avimimids Caenagnathids Gigantoraptor erlianensis See 152 Notes: Probably a basal caenagnathid rather than an oviraptorid. Epichirostenotes curreii See 151 Notes: New genus and species for Chirostenotes? unnamed species. Leptorhynchos gaddisi 1.5 m (5 ft) TL, 15 kg (30 lb) Fossil Remains: Partial skull and minority of skeletons. Anatomical Characteristics: Lower jaw short and broad. Tip of beak wide and upturned. Age: Late Cretaceous, Late Campanian. Distribution: Texas; Aguja. Habits: Upturned beak may be an adaptation for rooting in soil for plant and animal matter. Notes: Shared its habitat with at least one other caenagnathid species and a variety of other dinosaurs. Oddly shaped beak and presence of close relatives in the same habitat suggests niche partitioning via differences in feeding strategies within caenagnathids. The name Leptorhynchos is currently occupied by a plant, and will need to be changed in the future. Anzu wyliei See m (11 ft) TL, 200 kg (440 lb) Notes: New genus and species for Caenagnathus? unnamed species. Oviraptorids Ajancingenia yanshini 2 m (7 ft) TL, 40 kg (85 lb) Fossil Remains: Majority of skulls and skeletons. Anatomical Characteristics: Beak short and notably hooked. Hand short. Age: Late Cretaceous, Campanian. Distribution: Mongolia; Baruungoyot. Habitat: Semidesert with dunes and oases. 41

42 Notes: New genus for Ingenia yanshini. Remains placed in this genus from other formations are likely the growth stages of related forms. Considerable controversy surrounds the publication and use of this new name; it may not withstand the test of time. Headden Banji long Fossil Remains: Complete skull. Anatomical Characteristics: Relatively short crest bears horizontal striations. Nostrils elongated and follow curvature of crest. Small by oviraptorid standards. Age: Late Cretaceous, Late Maastrichtian. Distribution: Southern China; Nanxiong. Notes: Purpose of striations unclear, may have acted as an attachment point for a keratin extension. Xu ZP Machairasaurus leptonychus Fossil Remains: Minority of skeleton. 42

43 Anatomical Characteristics: Hand not large, claws relatively long and slender. Age: Late Cretaceous, Campanian. Distribution: Northern China; Bayan Mandahu. Habitat: Desert with dunes and oases. Habits: Long claws suitable for pulling down branches. Notes: Main enemies Velociraptor and Linhevenator. Luoyanggia liudianensis 1.5 m (5 ft) TL, 15 kg (30 lb) Fossil Remains: Minority skull and skeleton. Anatomical Characteristics: Beak of lower jaw pointed. Age: Early Late Cretaceous. Distribution: Eastern China; Mangchuan. Notes: Probably a rather primitive oviraptorid. Yulong mini Fossil Remains: Complete skull and majority of skeletons, embryos to subadults; eggs. Anatomical Characteristics: Much smaller than other derived oviraptorids. Snout not as high as in other oviraptorids and no crest present, but these features could be age related. Upper beak pointed and well developed. Age: Late Cretaceous, probably Campanian. Distribution: Central China; Qiupa. Habits: Gathered in groups to nest like other oviraptorids. Notes: Possibly the smallest derived oviraptorid. Proportions of legs similar at all ages, suggesting no change in feeding strategy upon maturity. Shared its habitat with Qiupalong. Main enemy Luanchuanraptor. Lü et al. Wulatelong gobiensis 1.5 m (5 ft) TL, 20 kg (45 lb) Fossil Remains: Partial skull and skeleton. Anatomical Characteristics: Lower jaw deep. Hands and claws slender. Age: Late Cretaceous, Campanian. Distribution: Northern China; Wulansuhai. Notes: Possibly the most basal known oviraptorid. 43

44 Headden Ganzhousaurus nankangensis Fossil Remains: Partial skull and skeleton. Anatomical Characteristics: Lower jaw shallow. Age: Late Cretaceous, Late Maastrichtian. Distribution: Southern China; Nanxiong. Notes: Appears to have had a mix of primitive and advanced features. Shared its habitat with several other oviraptorids and Gannansaurus. Jiangxisaurus ganzhouensis 1.5 m (5 ft) TL, 20 kg (45 lb) Fossil Remains: Partial skull and majority of skeleton. Anatomical Characteristics: Lower jaw not as downturned as relatives. Thumb robust. Age: Late Cretaceous, Late Maastrichtian. Distribution: Southern China; Nanxiong. Notes: Shared its habitat with several other oviraptorids. Nankangia jianxiensis 2 m (7 ft) TL, 40 kg (85 lb) Fossil Remains: Minority of skull and partial skeleton. Anatomical Characteristics: Lower jaw deep and U-shaped. Age: Late Cretaceous, Late Maastrichtian. Distribution: Southern China; Nanxiong. Habits: Probably more herbivorous than other oviraptorids. Notes: Appears to be a relatively basal oviraptorid. Shared its habitat with several other oviraptorids. Therizinosauroids Baso-Therizinosaurs 44

45 Martharaptor greenriverensis 4 m (12 ft) TL, 100 kg (220 lb) Fossil Remains: Minority of skeleton. Age: Early Cretaceous, Barremian. Distribution: Utah; upper Cedar Mountain. Habitat: Short wet season, otherwise semiarid with floodplain prairies, open woodlands, and riverine forests. Notes: Likely a close relative or descendant of Falcarius. Jianchangosaurus yixianensis Fossil Remains: Complete skull and majority of skeleton with feathers, juvenile. Anatomical Characteristics: Skull somewhat robust with a well-developed upper beak and a tooth arrangement like that of ornithischians. Hand not as elongated as Falcarius and lunate carpal not as well developed. Tapering band-like feathers at least over shoulders. It is not certain that the feet belong to this specimen. Age: Early Cretaceous, Early Aptian. Distribution: Northeast China; Yixian. Habitat: Well-watered forests and lakes. Habits: Likely a mid-level browser. Notes: More derived than Falcarius and larger than Beipiaosaurus when fully grown, it shared its habitat with the latter species as well as a wide variety of other dinosaurs. Relatively short neck and some other features may be juvenile traits. Main enemy Yutyrannus. Pu et al. 45

46 ZP Alxasaurids Therizinosaurids Sauropodomorphs Baso-Sauropodomorphs Pampadromaeus barberenai 1.5 m (5 ft) TL, 10 kg (25 lb) Fossil Remains: Majority of skull and skeleton. Anatomical Characteristics: Skull fairly large, front teeth heavily serrated. Arm short. Lower leg long. Age: Late Triassic, Carnian. Distribution: Southern Brazil; Santa Maria. Habits: Possibly more omnivorous than other baso-sauropods. Long lower legs indicate that it was a good runner. Notes: Possibly the most primitive sauropodomorph known. Prey of Staurikosaurus. Cabreira et al. 46

47 ZP Prosauropods Chromogisaurus novasi 2 m (6.5 ft) TL, 25 kg (50 lb) Fossil Remains: Partial skeleton. Age: Late Triassic, Carnian. Distribution: Northern Argentina; Ischigualasto. Habitat: Seasonally well-watered forests, including dense stands of conifers. Notes: Main enemies were herrerasaurs and large thecodonts. Chuxiongosaurus lufengensis Fossil Remains: Complete skull. Anatomical Characteristics: Snout subtriangular. Age: Early Jurassic, Hettangian. Distribution: Southern China; lower Lufeng. Notes: Appears to be the most basal known prosauropod from the Lufeng. Lü et al. Sarahsaurus aurifrontanalis 4.3 m (14 ft) TL, 200 kg (450 lb) Fossil Remains: Complete skull and majority of skeletons. 47

48 Anatomical Characteristics: Snout subtriangular, upper jaw slightly longer than lower. Hands unusually large and robust. Age: Early Jurassic, Sinemurian or Pliensbachian. Distribution: Arizona; Kayenta. Habitat: Partially arid. Habits: Large hands possibly adapted for digging up roots. Notes: Among the most primitive prosauropods known from North America. Colbert & Rowe Seitaad ruessi 3 m (10 ft) TL, 70 kg (150 lb) Fossil Remains: Partial skeleton. Age: Early Jurassic, Pliensbachian. Distribution: Utah; upper Glen Canyon. Notes: A basal prosauropod. ZP 48

49 Sertich & Loewen Aardonyx celestae Fossil Remains: Partial skulls and skeletons, juveniles. Anatomical Characteristics: Elastic cheeks greatly reduced, yet snout still narrow, nasal openings large. Limbs relatively robust. Orientation of limbs suggest more quadrupedal than other prosauropods, but still capable of slow bipedal motion. Age: Early Jurassic, Hettangian. Distribution: South Africa; Upper Elliot. Habitat: Some regions arid. Habits: Lack of large cheeks widened gape, allowing for bulk feeding similar to sauropods. Notes: A highly derived prosauropod, already showing adaptations for quadupedalism and bulk feeding. Yates Arcusaurus pereirabdalorum Fossil Remains: Minority of skull and skeleton. ZP 49

50 Age: Early Jurassic, Hettangian to Sinemurian. Distribution: South Africa; Upper Elliot. Habitat: Semi-arid. Notes: Thought to be a derived prosauropod, but too little is known to be certain. Efraasia (or Plateosaurus) minor See 166 Notes: Split from Plateosaurus (=Sellosaurus) gracilis. Many mostly complete specimens are awaiting further study. Glacialisaurus hammeri Fossil Remains: Minority of skeleton. Age: Early Jurassic, Sinemurian or Pliensbachian. Distribution: Central Antarctica; Hanson. Habitat: Polar forest with warm, daylight-dominated summers and cold, dark winters. Notes: May be another species of Plateosaurus, but too little is known to be certain. Main enemy Cryolophosaurus. Jaklapallisaurus asymmetrica Fossil Remains: Minority of skeleton. Age: Late Triassic, Late Norian or Early Rhaetian. Distribution: Central India; Upper Maleri. Leonerasaurus taquetrensis Fossil Remains: Minority of skull and skeleton. Anatomical Characteristics: Neck possibly more stiff than in other prosauropods. Age: Early Jurassic, probably Pliensbachian or Sinemurian. Distribution: Southern Argentina; Leoneras. Notes: A highly derived prosauropod. Nambalia roychowdhurii Fossil Remains: Partial skeletons. Age: Late Triassic, Late Norian or Early Rhaetian. Distribution: India; Upper Maleri. Notes: Two of the skeletons, a smaller and a larger individual, were found together. Xixiposaurus suni Fossil Remains: Majority of skull and partial skeleton. Anatomical Characteristics: Snout slants sharply downward. Age: Early Jurassic, Hettangian and/or Sinemurian. 50

51 Distribution: Southwest China; Lower Lufeng. Notes: A derived prosauropod. Unaysaurus (or Plateosaurus) tolentinoi 2.5 m (8 ft) TL, 40 kg (80 lb) Fossil Remains: Majority of skull and partial skeleton. Anatomical Characteristics: Head shallow, subrectangular. Arm relatively short. Age: Late Triassic, Norian. Distribution: Southern Brazil; Caturrita. Habits: Short arm indicates that this species was more bipedal than similar prosauropods. Notes: Establishes the presence of Plateosaurus-type prosauropods in the Southern Hemisphere. May include Teyuwasu barbarenai. Shared its habitat with Guaibasaurus. Elias Leyesaurus marayensis 2.5 m (8 ft) TL, 40 kg (80 lb) Fossil Remains: Majority of skull and minority of skeleton. Anatomical Characteristics: Skull subrectangular. Age: Early Jurassic. Distribution: Western Argentina; Quebrada de Barro. Notes: Appears to be a relative of Massospondylus. Apaldetti et al. 51

52 Sauropods Vulcanodonts Eusauropods Cetiosaurs Nebulasaurus taito Fossil Remains: Minority of skull. Age: Middle Jurassic. Distribution: Southern China; Zhanghe. Notes: Known only from a braincase. Closest relative appears to be Spinophorosaurus. Shared its habitat with Yuanmousaurus and Eomamenchisaurus. Euhelopids and Mamenchisaurids Notes: Euhelopids are likely basal titanosaurs and therefore not particularly closely related to mamenchisaurids. Tonganosaurus hei 11 m (35 ft) TL, 3.5 tonnes Fossil Remains: Partial skeleton. Age: Early Jurassic. Distribution: Central China; Yimen. Notes: If this is a mamenchisaurid, it is the earliest known. Huangshanlong anhuiensis Fossil Remains: Minority of skeleton. Age: Middle Jurassic. Distribution: Eastern China; Hongqin. Notes: Only known from an arm, but most likely belongs with mamenchisaurids. Xinjiangtitan shanshanesis 32 m (105 ft) TL, 70 tonnes Fossil Remains: Partial skeleton. Anatomical Characteristics: Hindlimbs relatively short. Age: Middle Jurassic, Aalenian. Distribution: Northwestern China; Qigu. Notes: One of the first gigantic sauropods. 52

53 Gannansaurus sinensis Fossil Remains: Vertebrae. Age: Late Cretaceous, Late Maastrichtian. Distribution: Southern China; Nanxiong. Notes: Shows that euhelopid sauropods, be they titanosauriformes or not, survived to the end of the Cretaceous. Shared it habitat with a variety of oviraptorids. Turiasaurs Zby atlanticus Fossil Remains: Minority of skull and skeleton. Age: Late Jurassic, Late Kimmeridgian. Distribution: Portugal; Lourinhã. Habitat: Large, seasonally dry island with open woodlands. Notes: Main enemies included Allosaurus, and Torvosaurus. Neosauropods Diplodocoids Rebbachisaurids Comahuesaurus windhauseni 14 m (45 ft) TL, 7 tonnes Fossil Remains: Minority of skeleton. Age: Early Cretaceous, Aptian or Albian. Distribution: Western Argentina; Lohan Cura. Notes: Previously thought to be a species of Limaysaurus, appears to be a more basal rebbachisaurid. Demandasaurus darwini Fossil Remains: Minority of skull and skeleton. Age: Early Cretaceous, Late Barremian or Early Aptian. Distribution: Spain; Castrillo la Reina. Notes: Closest relative appears to be Nigerasaurus. Tataouinea hannibalis 14 m (45 ft) TL, 7 tonnes Fossil Remains: Minority of skeleton. Anatomical Characteristics: Skeleton shows extensive pneumaticity. 53

54 Age: Early Cretaceous, Early Albian. Distribution: Tunisia; Ain el Guettar. Habitat: Tropical floodplain surrounded by arid regions. Notes: Demonstrates that sauropods could, at least occasionally, exhibit levels of skeletal pneumaticity previously known only amongst birds, theropods, and pterosaurs. Shared its habitat with a variety of large theropods. Dicraeosaurids Diplodocids Diplodocines Kaatedocus siberi Fossil Remains: Complete skull and minority of skeleton. Anatomical Characteristics: Skull shallow. Age: Late Jurassic, Kimmeridgian. Distribution: Wyoming; lower Morrison. Habitat: Short wet season, otherwise semiarid with open floodplain prairies and riverine forests. Habits: Primarily a high-level browser. Notes: Originally placed in Barosaurus lentus. Leinkupal laticauda 9 m (29 ft) TL, 2 tonnes Fossil Remains: Minority of skeleton. Anatomical Characteristics: Broad tail vertebrae. Age: Early Cretaceous, Late Berriasian. Distribution: Southern Argentina; Bajada Colorada. Notes: The youngest diplodocine diplodocid and the first from South America. Apatosaurines Macronarians ZP 54

55 Macronarian Miscellanea Camarasaurids Cathetosaurus lewisi See 199 Notes: New genus for Camarasaurus lewisi. Brontomerus mcintoshi 14 m (46 ft) TL, 10 tonnes Fossil Remains: Minority of skeletons, juvenile and adult. Anatomical Characteristics: Hips unusually large, probably to support large leg muscles. Age: Early Cretaceous, Late Aptian or early Albain. Distribution: Utah; lower Cedar Mountain. Habitat: Short wet season, otherwise semiarid with floodplain prairies and open woodlands, and riverine forest. Habits: Defenses included kicking with hind legs. Notes: Relationship to other sauropods unclear. Juvenile and adult found in association. Titanosauriformes Titanosauriform Miscellanea Liubangosaurus hei Fossil Remains: Minority of skeleton. Age: Early Cretaceous, Aptian or Albian. Distribution: Southern China; Napai. Notes: May be congeneric with Fusuisaurus, but too little is known to be certain. Brachiosaurids Astrophocaudia slaughteri Fossil Remains: Minority of skeleton. Age: Early Cretaceous, Albian. Distribution: Texas, Oklahoma; Glen Rose, Antlers. Habitat: Floodplain with coastal swamps and marshes. Notes: Portions of remains originally placed in Pleurocoelus and/or Paluxysaurus. Titanosaurids Baso-Titanosaurs 55

56 Agustinia ligabuei See 205 Notes: Some researchers have concluded that Agustinia s bizarre armor is actually just bone that became warped and eroded during the fossilization process. Tambatitanis amicitiae Fossil Remains: Minority of skull and skeleton. Age: Early Cretaceous, Albian. Distribution: Japan; Sasayama. Notes: Probably part of unique East Asian radiation of titanosaurs. Yunmenglong ruyangensis Fossil Remains: Minority of skeleton. Anatomical Characteristics: Neck relatively long. Age: Late Early Cretaceous, Aptian or Albian. Distribution: Central China; Haoling. Notes: Closest relative appears to be Qiaowanlong. Rukwatitan bisepultus 9 m (30 ft) TL, 3 tonnes Fossil Remains: Partial skeleton. Age: Middle Cretaceous. Distribution: Tanzania; Galula. Notes: Suggests that unique titanosaur lineages occurred in northern and southern Africa during this part of the Cretaceous. Lithostrotians Atacamatitian chilensis Fossil Remains: Minority of skeleton. Age: Late Cretaceous, probably Campanian or Maastrichtian. Distribution: Chile; Tolar. Notes: If adult, this was a relatively small titanosaur. Atsinganosaurus velauciensis 10 m (33 ft) TL, 5 tonnes Fossil Remains: Partial skeleton. Age: Late Cretaceous, Early Maastrichtian. Distribution: France; Grès à Reptiles. Notes: Shared its habitat with other sauropods and Pyroraptor. 56

57 Drusilasaura deseadensis 25 m (80 ft) TL, 50 tonnes Fossil Remains: Partial skeleton. Age: Late Cretaceous, Cenomanian or Turonian. Distribution: Southern Argentina; Bajo Barreal. Notes: Shared its habitat with larger Elaltitan. Elaltitan lilloi 30+ m (100+ ft) TL, 80+ tonnes Fossil Remains: Partial skeleton. Age: Late Cretaceous, Late Cenomanian or Early Turonian. Distribution: Southern Argentina; Bajo Barreal. Notes: Among the largest of sauropods. Fukuititan nipponensis 13 m (45 ft) TL, 5 tonnes Fossil Remains: Partial skeleton. Age: Early Cretaceous, Barremian. Distribution: Japan; Kitadani. Notes: Shared its habitat with Fukuiraptor and Fukuisaurus. Narambuenatitan palomoi Fossil Remains: Partial skull and skeleton, large juvenile. Anatomical Characteristics: Snout not short. Age: Late Cretaceous, Early Campanian. Distribution: Northern Argentina; Anacleto. Notes: Main enemies Abelisaurus and Aerosteon. Panamericansaurus schroederi 11 m (35 ft) TL, 2.5 tonnes Fossil Remains: Minority of skeleton. Age: Late Cretaceous, Campanian. Distribution: Central Argentina; Allen. Habitat: Semiarid coastline. Notes: Closely related to Aeolosaurus. Petrobrasaurus puestohernandezi 18 m (60 ft) TL, 15 tonnes Fossil Remains: Minority of skull and skeleton. Anatomical Characteristics: Age: Late Cretaceous, Santonian. Distribution: Southern Argentina; Plottier. 57

58 Rugocaudia cooneyi Fossil Remains: Minority of skeleton. Age: Early Cretaceous, Albian. Distribution: Montana; Cloverly. Habitat: Short wet season, otherwise semiarid with floodplain prairies and open woodlands, and riverine forests. Notes: Suggests that sauropods may have persisted in North America throughout the Cretaceous. Some researches consider this to be a dubious genus. Main enemy Acrocanthosaurus. Tapuiasaurus macedoi 13 m (43 ft) TL, 8.5 tonnes Fossil Remains: Complete skull and partial skeleton. Anatomical Characteristics: Head long, shallow, bony nostrils strongly retracted to above orbits but fleshy nostrils probably still near front of snout, which is broad, rounded, lower jaws short; pencilshaped teeth limited to front of jaws, head flexed downward relative to neck. Skeleton robust. Age: Early Cretaceous, Aptian. Distribution: Southeast Brazil; Quiricó. Habits: Probably capable of browsing at most levels. Notes: The earliest known advanced titanosaur. Sanches Yongjinglong datangi 13 m (45 ft) TL, 5 tonnes Fossil Remains: Minority of skull and skeleton. Anatomical Characteristics: Scapula very large. Age: Late Early Cretaceous. Distribution: Northern China; Hekou Group. Notes: Shared its habitat Daxiatitan and Huanghetitan. Overosaurus paradasorum 10 m (33 ft) TL, 5 tonnes Fossil Remains: Minority of skeleton. Age: Late Cretaceous, Early Campanian. 58

59 Distribution: Central Argentina; Anacleto. Habitat: Semiarid coastline. Notes: Shared its habitat with a variety of other sauropods. Main enemies abelisaurids and Aerosteon. Brasilotitan nemophagus 7 m (23 ft) TL, 1 tonne Fossil Remains: Minority of skull and skeleton. Anatomical Characteristics: Lower jaw strongly squared-off, neck relatively short. Age: Late Cretaceous, probably Campanian or Maastrichtian. Distribution: Southern Brazil; Adamantina. Habits: Probably a low-level grazer. Notes: Related to Bonitasaura, but does not appear to have possessed a beak. Normanniasaurus genceyi Fossil Remains: Minority of skeleton. Age: Early Cretaceous, Albian. Distribution: France; Poudingue Ferrugineux. Notes: A relatively basal titanosaur. Dreadnoughtus schrani 26+ m (85+ ft) TL, 50+ tonnes Fossil Remains: Minority of skull and majority of skeletons. Anatomical Characteristics: Skeleton well pneumatisized, shorter limbs than most other gigantic titanosaurs, neck proportionally long. Age: Late Cretaceous, late Campanian or early Maastrichtian. Distribution: Argentina; Cerro Fortaleza. Habitat: Large rivers present. Habits: Likely a generalist browser, able to feed on both groundcover and in the treetops. Notes: The most complete gigantic titanosaurs discovered thus far. The largest known specimen is skeletally immature, but likely still an adult capable of breeding. Specimens show signs of scavenging by small theropods. Lacovara et al. Quetecsaurus rusconii 15 m (50 ft) TL, 10 tonnes Fossil Remains: Minority of skull and partial skeleton. 59

60 Age: Late Cretaceous, Turonian. Distribution: Western Argentina; Cerro Lisandro. Habitat: Swamps present. Vahiny depereti Fossil Remains: Minority of skull. Age: Late Cretaceous, Campanian. Distribution: Madagascar; Maevarano. Habitat: Seasonally dry floodplain with coastal swamps and marshes. Notes: Shared its habitat with Rapetosaurus, to which it was not closely related. Main enemy Majungasaurus. Saltasaurs Ornithischians Baso-Ornithischians Laquintasaura venezuelae 1 m (3.5 ft) TL, 1 kg (2 lb) Fossil Remains: Majority of skull and skeleton. Anatomical Characteristics: Skull more robust than other baso-ornithischians. Age: Early Jurassic, Hettangian. Distribution: Venezuela; La Quinta. Notes: Likely prey of Tachiraptor. Genasaurs Thyreophorans Barrett et al. 60

61 Scelidosaurs Bienosaurus lufengensis Fossil Remains: Minority of skull and skeleton. Age: Early Jurassic, Hettangian. Distribution: Southern China; lower Lufeng. Notes: Main enemy Sinosaurus triassicus. Shared its habitat with prosauropods. Euryopods Stegosaurs Huayangosaurids Stegosaurids Ankylosaurs Minmids Chuanqilong chaoyangensis Adult size uncertain Fossil Remains: Majority of skull and skeleton. Anatomical Characteristics: Tail club probably absent, full extent of armor uncertain. Age: Early Cretaceous, Aptian. Distribution: Northeast China; Jiufotang. Habitat: Well-watered forests and lakes. Notes: Closely related to Liaoningosaurus, with which it shared its habitat. Like Liaoningosaurus, possibly not a minmid. Polacanthians Taohelong jinchengensis 5 m (17 ft) TL, 1.9 tonnes Fossil Remains: Minority of skeleton. Anatomical Characteristics: Irregularly shaped osteoderms on sacral shield. Age: Early Cretaceous. Distribution: Central China; Hekou Group. Notes: Closely related to Polacanthus. Ankylosaurids Zhongyuansaurus luoyangensis 61

62 Fossil Remains: Majority of skull and minority of skeleton. Anatomical Characteristics: Skull shallow, lacked tail club. Age: Early Late Cretaceous. Distribution: Eastern China; unknown. Notes: Possibly the basal most ankylosaurid. If not, then it may be a polacanthian or a basal nodosaur. Zaraapelta nomadis 5 m (16 ft) TL, 2 tonnes Fossil Remains: Majority of skull and minority of skeletons. Anatomical Characteristics: Double-row of osteoderms on top of skull, conical hornlets on the upper rim of orbits, four prominent postorbital horns. Beak blunt. Elongated osteoderm runs majority of the length of lower jaw. Tail club present but shape uncertain. Age: Late Cretaceous, Campanian. Distribution: Mongolia; Baruungoyot. Habitat: Seasonal woodland. Notes: Closely related to Tarchia and Saichania, with which it shared its environment. Highly ornamented cranium possibly a sexual display. Arbour et al. Anodontosaurus lambei See 234 Notes: Resurrected genus and species for Euplocephalus unnamed species. Scolosaurus cutleri 6 m (20 ft) TL, 2 tonnes Fossil Remains: Majority of skull and minority of skeletons. Anatomical Characteristics: Hornlets at back of skull and under eyes are large, three-sided, and triangular; eye sockets large. Osteoderms have a smooth surface. Limbs robust. Tail club modest-sized and heart-shaped when viewed from above. Age: Late Cretaceous, Late Campanian. Distribution: Montana; Upper Two Medicine. Habitat: Seasonally dry upland woodlands. Notes: Split from Euoplocephalus tutus. Skull of one specimen shows evidence of being stepped on. Shared its habitat with Edmontonia and a wide variety of other dinosaurs. Probably includes Oohkotokia horneri. 62

63 Dyoplosaurus acutosquameus 5 m (16 ft) TL, 2 tonnes Fossil Remains: Minority of skull and partial skeleton. Anatomical Characteristics: Tail club very narrow. Age: Late Cretaceous, Late Campanian. Distribution: Alberta; Lower Dinosaur Park. Habitat: Well-watered, forested floodplain with coastal swamps and marshes, cool winters. Notes: Split from Euoplocephalus tutus. Ziapelta sanjuanensis 5.5 m (18 ft) TL, 2.5 tonnes Fossil Remains: Majority of skull and minority of skeleton. Anatomical Characteristics: Large postorbital horns. Six large spines on cervical rings. Age: Late Cretaceous, Campanian. Distribution: New Mexico; Kirtland. Habitat: Moderately watered floodplain woodlands, coastal swamps and marshes. Notes: Shared its habitat with Nodocephalosaurus. Main enemy Bistahieversor. Ahshislepelta minor 4 m (12 ft) TL, 1 tonne Fossil Remains: Minority of skeleton. Anatomical Characteristics: Osteoderms have a knobby texture. Age: Late Cretaceous, Late Campanian. Distribution: New Mexico; Kirtland. Habitat: Moderately watered floodplain woodlands, coastal swamps and marshes. Notes: Smallest ankylosaurid in region. Main enemy Bistahieversor. Nodosaurids Propanoplosaurus marylandicus Fossil Remains: Natural cast of a young juvenile including most of the body and head. Anatomical Characteristics: Only osteoderms on head well developed. Age: Early Cretaceous, Late Aptian. Distribution: Maryland; Patuxent. Notes: Reduced armor is likely a condition only present in young juveniles. Tatankacephalus cooneyorum 6 m (20 ft) TL, 3.5 tonnes Fossil Remains: Partial skull and minority of skeleton. Anatomical Characteristics: Skull domed and with a ridge along back edge. Age: Early Cretaceous, Late Aptian or Early Albian. Distribution: Montana; Cloverly. Habitat: Short wet season, otherwise semiarid with floodplain prairies, open woodlands, and riverine forests. Notes: Placement uncertain. Shared its habitat with Sauropelta, Tenontosaurus, and Deinonychus. 63

64 Dongyangopelta yangyanensis 4.5 m (15 ft) TL, 1.4 tonnes Fossil Remains: Minority of skeleton. Anatomical Characteristics: Pelvic shield fused with moderately-sized, smooth, rounded osteoderms; other osteoderms have a very rough surface indicating they once supported larger attachments. Age: Early Late Cretaceous, Cenomanian. Distribution: East China; Chaochuan. Notes: Shared its habitat with fellow nodosaurid Zhejiangosaurus. Europelta carbonensis 4.5 m (15 ft) TL, 1.4 tonnes Fossil Remains: Majority of skull and partial skeletons. Anatomical Characteristics: Nostrils rather large, moderately sized jugal ridges present. Subrectangular osteoderms cover neck gradually becoming more oval shaped toward hips. Three moderately sized shoulder spines, largest toward front. Plate-like osteoderms along sides of hips and tail have a rounded margin. Age: Early Cretaceous, Early Albian. Distribution: Spain; Escucha. Notes: Oldest European nodosaurid, suggests that nodosaurids replaced polacanthian ankylosaurs in Europe during the latter part of the Cretaceous, just as they did in North America. Shared its habitat with Proa. Hartman ZP 64

65 Kirkland et al. Heterodontosauriformes Heterodontosaurids Tianyulong confuciusi See 240 Age: Late Jurassic, Oxfordian. Distribution: Northeast China; Tiaojishan. Manidens condorensis 0.75 m (2.5 ft) TL, 0.8 kg (1.8 lb) Fossil Remains: Complete skull and partial skeleton. Anatomical Characteristics: Snout shorter than relatives, short fangs present. Age: Middle Jurassic, Aalenian or Early Bathonian. Distribution: Northern Argentina; Cañadón Asfalto. Notes: Main enemies Piatnitzkysaurus, Condorraptor, and Eoabelisaurus. Shared its habitat with many sauropods. Pol et al. Pegomastax africana 1.2 m (4 ft) TL, 3.5 kg (7.5 lb) Fossil Remains: Partial skull. Anatomical Characteristics: Beak and lower jaw robust. Age: Early Jurassic, Hettangian or Sinemurian. 65

66 Distribution: South Africa; Upper Elliot. Habitat: Arid. Notes: Shared its habitat with Heterodontosaurus, which it was not particularly closely related to. Prey of Coelophysis. Marginocephalians Pachycephalosaurids Acrotholus audeti 1.5 m (5 ft) TL, 10 kg (20 lb) Fossil Remains: Skull dome. Anatomical Characteristics: Skull heavily reinforced despite small size. Age: Late Cretaceous, Late Santonian. Distribution: Alberta; Milk River. Notes: The earliest fully domed pachycephalosaurid known from North America. Amtocephale (or Stegoceras) gobiensis Fossil Remains: Skull dome. Age: Late Cretaceous, Turonian or Santonian. Distribution: Mongolia; Bayan Shireh. Notes: Main enemy Achillobator. Shared its habitat with Garudimimus. Stegoceras? novomexicanum 1.5 m (5 ft) TL, 10 kg (20 lb) Fossil Remains: Minority of skulls. Age: Late Cretaceous, Late Campanian. Distribution: New Mexico; Fruitland, Kirtland. Habitat: Floodplain woodlands. Notes: It is not certain that this species belongs in Stegoceras. Ceratopsians Chaoyangosaurs Paxceratopsians Psittacosaurids Neoceratopsians Protoceratopsids 66

67 Aquilops americanus 0.6 m (2 ft) TL, 2 kg (4 lb) Fossil Remains: Majority of skull, possibly juvenile. Anatomical Characteristics: Beak of upper jaw strongly hooked with a distinct knob on its anterior edge, which may have been enlarged with keratin to form a short horn or crest. Beak of lower jaw relatively straight and pointed. Rear of skull flares outwards giving a highly triangular profile when viewed from above. Age: Early Cretaceous, Albian. Distribution: Montana; Cloverly. Habitat: Short wet season, otherwise semiarid with floodplain prairies and open woodlands, and riverine forests. Habits: Low-level browser. Beak ornamentation likely for display, but could have also assisted in rooting in soil for food. Notes: The oldest and most primitive ceratopsian known from North America. Its closest relatives appear to be from Asia, indicating multiple faunal exchanges between Asia and North America during the Cretaceous, probably via an intermittent land bridge across the Bering Sea. Main enemy Deinonychus. Farke et al. ZP Farke et al. Archaeoceratops yujingziensis 0.5 m (1.7 ft) TL, 2 kg (4 lb) Fossil Remains: Partial skeleton. Anatomical Characteristics: Insufficient information Age: Early Cretaceous, Aptian. Distribution: Central China; Xinminbao. Habitat: Well-watered forest and lakes. Notes: Potential synonymous with A. oshimai, with which it shared its environment. 67

68 Ajkaceratops kozmai 1.1 m (3.5 ft) TL, 10 kg (20 lb) Fossil Remains: Minority of skull. Age: Late Cretaceous, Santonian. Distribution: Hungary; Csehbánya. Notes: The first ceratopsian known form Europe. Shared its habitat with Hungarosaurus. Gryphoceratops morrisoni 0.5 m (1.7 ft) TL, 2 kg (4 lb) Fossil Remains: Minority of skull. Age: Late Cretaceous, Late Santonian. Distribution: Alberta; Milk River. Notes: The smallest ceratopsian known from North America. Koreaceratops hwaseongensis 0.9 m (3 ft) TL, 10 kg (20 lb) Fossil Remains: Minority of skeleton. Anatomical Characteristics: Vertebral spines over tail form an ascending sail, tallest near the end. Age: Early Cretaceous, Albian. Distribution: South Korea; Tando Beds. Notes: Purpose of sail-tail unclear, probably not used for swimming, more likely for display. Unescoceratops koppelhusae 1.3 m (4.3 ft) TL, 20 kg (40 lb) Fossil Remains: Minority of skull. Anatomical Characteristics: Teeth highly rounded. Age: Late Cretaceous, Late Campanian. Distribution: Alberta; Dinosaur Park. Habitat: Well-watered forests. Habits: Purpose of unusual teeth unclear, may have been for cracking nuts or eating gritty foods. Zhuchengceratops inexpectus 2.5 m (8 ft) TL, 175 kg (380 lb) Fossil Remains: Minority of skull and partial skeleton. Anatomical Characteristics: Lower jaw deep. Age: Late Cretaceous, probably Campanian. Distribution: Eastern China; Wangshi Group. Notes: Shared its habitat with Sinoceratops, Tanius, and Tsintaosaurus. Prey of Zhuchengtyrannus. Ceratopsids Centrosaurines Xenoceratops (or Albertaceratops) foremostensis 68

69 6 m (20 ft) TL, 3 tonnes Fossil Remains: Partial skull. Anatomical Characteristics: Modest sized brow horns curve forward, nasal boss low. Frill subhorizontal, concave, and slightly indented; a pair of flattened spines adorn top with another smaller pair on sides, small hornlets between. Age: Late Cretaceous, Middle Campanian. Distribution: Alberta; Foremost. Habitat: Well-watered, forested floodplain with coastal swamps and marshes, cool winters. Notes: The oldest centrosaurine known from Alberta. Medusaceratops (or Albertaceratops) lokii 6 m (20 ft) TL, 3 tonnes Fossil Remains: Partials skulls. Anatomical Characteristics: Nasal boss low and narrow, frill subvertical, back rim bore a pair of massive, sideways-arcing spikes, smaller sideways-arcing spikes rim sides. Age: Late Cretaceous, Middle Campanian. Distribution: Alberta; Judith River. Habitat: Well-watered, forested floodplain with coastal swamps and marshes and drier upland woodlands. Habits: Spikes rimming frill may have been used in defense. Notes: Originally placed in Albertaceratops nesmoi, may be the same genus or species. Nasutoceratops (or Albertaceratops) titusi 4.5 m (15 ft) TL, 1.2 tonnes Fossil Remains: Majority of skull and minority of skeleton. Anatomical Characteristics: Frill short and nearly horizontal with small hornlets lining rim and at base of median bar. Brow horns moderately long, point forward, curving inward and up. Nasal region strongly expanded upward, nasal boss nearly absent. Age: Late Cretaceous, Late Campanian. Distribution: Utah; Kaiparowits. Habits: Inward curving horns better suited for conflicts within own species than in defense. Notes: Shared its habitat with Kosmoceratops and Utahceratops, along with a variety of other dinosaurs. Main enemy Teratophoneus. 69

70 Sampson et al. ZP Sampson et al. Spinops (or Centrosaurus) sternbergorum 6 m (20 ft) TL, 3 tonnes Fossil Remains: Partial skull. Anatomical Characteristics: Nasal horn medium-sized, brow horns small. Frill subhorizontal, two large spikes on back rim, two smaller downward curving spikes in front of these. Age: Late Cretaceous, Campanian. Distribution: Alberta; upper Oldman or lower Dinosaur Park. Habitat: Well-watered, forested floodplain with coastal swamps and marshes. Notes: May or may not be a distinct genus from Centrosaurus. Main enemy Daspletosaurus. Coronosaurus (or Centrosaurus) brinkmani See 260 Notes: New genus for Centrosaurus brinkmani, as found to phylogenetically closer to Styracosaurus than Centrosaurus. Rubeosaurus (or Centrosaurus) ovatus See 262 Notes: New genus for Styracosaurus ovatus. Pachyrhinosaurus (or Centrosaurus) perotorum 5 m (17 ft) TL, 2 tonnes 70

71 Fossil Remains: Partials skulls, juvenile and adult. Anatomical Characteristics: In mature adults, very large nasal boss possesses a raised central area and nearly connects with smaller bosses over eyes; heavily pitted surface of bosses suggest they were enlarged with keratin in life. Frill subhorizontal with two sideways arcing blades at the top of the rim, central region and rim lined with small hornlets. Beak relatively blunt. Age: Late Cretaceous, Late Maastrichtian. Distribution: Alaska; Prince Creek. Habitat: Polar forest with warm humid summers and cold dark winters. Notes: Main enemy Nanuqsaurus. Fiorillo and Tykoski Sinoceratops zhuchengensis 6 m (20 ft) TL, 3 tonnes Fossil Remains: Partial skull. Anatomical Characteristics: Nasal horn medium-sized, brow horns very small. Frill subvertical, rimmed with flattened triangular spines that curve forward, bony knobs rim front outer edge. Age: Late Cretaceous, Campanian. Distribution: Eastern China; Wangshi Group. Notes: The only centrosaurine ceratopsid known from Asia, probably represents an incursion from North America. Shared its habitat with a variety of hadrosaurs. Prey of Zhuchengtyrannus. Panzarin ZP Ceratopsines Chasmosaurines Anchiceratops ornatus 71

72 See 268 Notes: It is not certain that the holotype skull belongs with the skeleton that it was assigned to. Torosaurus latus (and/or utahensis) 8.5 m (28 ft) TL, 10 tonnes See page 266 Fossil Remains: Majority of skulls and skeletons, juvenile to adult. Anatomical Characteristics: Snout shallow, nasal horn small, brow horns long and straight. Frill greatly elongated with two large openings, rimmed by small hornlets. Skeleton robust. Age: Late Cretaceous, Late Maastrichtian. Distribution: Saskatchewan, Montana, Wyoming, Dakotas; Frenchman, Laramie, Denver, Hell Creek. Habitat: Well-watered forests to dry woodlands. Habits: Low-level browser. Frill used mainly for display, brow horns for defense against predators and in conflicts with own species. Notes: Resurrected genus and species from Triceratops horridus, where it was previously considered the fully mature form. Discovery of mislabeled juvenile remains were the cause; however, these remains are from the more westerly Torosaurus utahensis (shown here), which may actually be a different genus. In the possible event that T. latus is refound to be a form of Triceratops, T. utahensis would take on the genus name Torosaurus. If instead, T. latus is confirmed to be distinct, then T. utahensis will likely be placed in a new genus. Either way, Torosaurus is valid. Classification as a chasmosaurine is not certain. Hunt & Lehman Kosmoceratops richardsoni 5 m (17 ft) TL, 2 tonnes Fossil Remains: Majority of skull and skeleton. Anatomical Characteristics: Brow horns short, curve down perpendicular to the skull. Nasal horn short and thin. Frill is wider than long, slightly concave, with ten short downward curving horns lining the top, small hornlets along sides. Frill openings small. Age: Late Cretaceous, Late Campanian. Distribution: Utah, Alberta; Kaiparowits, Dinosaur Park. 72

73 Notes: Shortness of frill and small frill openings separate this genus from closely related Chasmosaurus. Main enemy Teratophoneus. Presence in Alberta uncertain. Sampson et al. ZP Sampson et al. Coahuilaceratops (or Chasmosaurus) magnacuerna 6.4 m (21 ft) TL, 4.7 tonnes Fossil Remains: Partial skull. Anatomical Characteristics: Brow horns very large, curve forward. 73

74 Age: Late Cretaceous, Late Campanian. Distribution: Northern Mexico; Cerro del Pueblo. Notes: Shared its habitat with Hypacrosaurus (=Velafrons) coahuilensis. Mojoceratops (or Chasmosaurus) perifania 4.3 m (14 ft) TL, 1.5 tonnes Fossil Remains: Partial skulls and minority of skeleton. Anatomical Characteristics: Brow horns long and arch sideways. Nasal horn short. Frill subhorizontal, back rim very broad and forms a shallow U, corners bore large hornlets, small hornlets along rims. Age: Late Cretaceous, Late Campanian. Distribution: Alberta; Dinosaur Park. Habitat: Well-watered, forested floodplain with coastal swamps and marshes, cool winters. Notes: Split from Chasmosaurus russelli, may still be the same genus or species, perhaps as the fully mature or male form. Mercuriceratops (or Chasmosaurus) gemini 6 m (20 ft) TL, 3 tonnes Fossil Remains: Minority of skulls. Anatomical Characteristics: Frill subhorizontal, squamosal region of frill flares out into small wing-like processes rimmed with small hornlets. Age: Late Cretaceous, Campanian. Distribution: Alberta, Montana; Judith River, Dinosaur Park. Habitat: Well-watered forests and floodplains. Notes: Unique frill ornaments likely enhanced display of frill. Utahceratops (or Pentaceratops) gettyi 6 m (20 ft) TL, 3 tonnes Fossil Remains: Complete skull and majority of skeletons. Anatomical Characteristics: Nasal horn short and placed high on snout, brow horns very short and point to the sides. Frill subhorizontal, broadest at base, large vertical frill openings placed high up, strongly indented, large hornlets at top decrease in size down sides. Age: Late Cretaceous, Late Campanian. Distribution: Utah; Kaiparowits. Notes: May be a species of Pentaceratops or Chasmosaurus. Shared its habitat with Kosmoceratops. Main enemy Teratophoneus. 74

75 Sampson et al. ZP Sampson et al. 75

76 Vagaceratops (or Chasmosaurus) irvinensis See 270 Notes: New genus for Chasmosaurus irvinensis. Judiceratops (or Chasmosaurus) tigris 4.5 m (15 ft) TL, 1.2 tonnes Fossil Remains: Partial skull. Anatomical Characteristics: Frill rounded with a thick midline bar, hornlets large at base of frill and decrease in size toward rear. Brow horns moderately long and splay forward and outward slightly, teardrop shaped in cross section. Age: Late Cretaceous, Middle Campanian. Distribution: Montana; Judith River. Habitat: Well-watered, forested floodplain with coastal swamps and marshes. Notes: The oldest known chasmosaurine. Pentaceratops (or Chasmosaurus) aquilonius Fossil Remains: Minority of skull. Age: Late Cretaceous, Late Campanian. Distribution: Alberta; Dinosaur Park. Habitat: Well-watered forest and floodplain with coastal marshes and cool winters. Notes: Validity questionable, probably belongs in a species of Chasmosaurus. Bravoceratops (or Pentaceratops) polyphemus 8 m (25 ft) TL, 9 tonnes Fossil Remains: Minority of skull. Anatomical Characteristics: Snout narrow, frill long and tall with large openings and a fan-shaped median bar. Brow horns moderately large, nasal horn small. Age: Late Cretaceous, Early Maastrichtian. Distribution: Texas; Javelina. Habitat: Seasonally dry open woodlands. Notes: Possibly ancestral to Torosaurus? utahensis, as features are intermediate of advanced chasmosaurines such as Torosaurus and less advanced forms such as Coahuilaceratops (or Pentaceratops), the latter of which appears to be close relative. Main enemy Tyrannosaurus. Wick and Lehman 76

77 Titanoceratops (or Pentaceratops) ouranos 9 m (30 ft) TL, 11 tonnes Fossil Remains: Majority of skull and partial skeleton. Anatomical Characteristics: Nasal horn short, brow horns long and curve forward. Frill probably elongated, tilted upward. Belly broad, and hind legs bowed. Age: Late Cretaceous, Campanian. Distribution: New Mexico; upper Fruitland or lower Kirtland. Habitat: Moderately watered floodplain woodlands, coastal swamps and marshes. Notes: Split from Chasmosaurus (Pentaceratops) sternbergi. Other remains placed in the former genus could belong here, but this is not certain. Ornithopods Longrich Hypsilophodonts Notes: This is likely a waste-basket group containing a number of superficially similar forms. Kulindadromeus zabaikalicus 1.5 m (4.5 ft) TL, Fossil Remains: Majority of skulls and skeletons, juvenile to adult, filament and scale impressions. Anatomical Characteristics: Snout subtriangular, jaws tipped with a short blunt beak. Eyes fairly large. Remainder of body fairly standard for small hypsilophodontid-type ornithischian. Short (up to 3 cm) filaments cover body, neck, upper arm, leg down to shin, and at least most of head; these fall into three categories: standard hair-like filaments cover majority; upper arm and thigh covered in groups of hexagonal non-overlapping scale-like structures each of which bears 6-7 filaments projecting downward from it (up to 1.5 cm); leg below knee down to mid shin covered in bundles of ribbon-like structures (up to 2 cm) each which is composed of many much smaller filaments. Small scales are present on exposed portions of limbs and tail; overlapping hexagonal scales on lower shins and non-overlapping rounded scales on the remainder of the limbs. At least five overlapping rows of rectangular scales cover tail, 77

78 largest at the top and decreasing with size ventrally, each scale possesses a forward facing prong on its leading edge, scales at end of tail are smaller, rounded, and non-overlapping Age: Mid to Late Jurassic, late Bajocian to early Tithonian. Distribution: East Russia; Ukureyskaya. Habitat: Habits: Low-level browsing herbivore, probably eating small animals on occasion. Well suited for running and possibly burrowing. Specimens found in association suggest some sort of herding behavior. Notes: Filamental covering used for insulation, longer ribbon-like structures may have been for display. Overlapping rows of scales on tail may have helped keep the tail keep rigid and/or acted as low grade armor for protection against small predators. If the filaments are homologous to the feathers of theropods, it is likely that the origin of filamental coverings can be extended to the base of dinosauria, and possibly even further to the common ancestor of dinosaurs and pterosaurs. Kulindadromeus likely falls outside of hypsilophodonts, but is placed here until the taxonomy of this group is sorted out. Kulindapteryx and Daurosaurus are invalid synonyms of this species. Godefroit et al. Hexinlusaurus multidens See 274 Notes: New genus for Agilisaurus? unnamed species. Slightly more derived than Agilisaurus. ZP 78

79 Leaellynasaura amicagraphica See 276 Anatomical Characteristics: Eyes large, tail exceptionally long and flexible. Notes: If a dense covering of fibers were present, flexible tail could have been used for insulation while at rest; potential other uses include a balancing aid or means of visual communication to other members of the group. Gideonmantellia amosanjuanae Fossil Remains: Partial skeleton, juvenile. Age: Early Cretaceous, Barremian. Distribution: Spain; Camarillas. Notes: Closest relatives appear to be in North America. Prey of Camarillasaurus. Haya griva 2 m (6.5 ft) TL, 20 kg (45 lb) Fossil Remains: Complete skull and majority of skeletons, juvenile and adult. Gastroliths. Anatomical Characteristics: Skull subtriangular with pointed beak. Legs robust. Age: Late Cretaceous, Santonian. Distribution: Mongolia; Javkhlant. Habitat: Swallowed gastroliths to help digest plant matter. Probably not as agile as similar species. Notes: Shared its habitat with Yamaceratops. Buchholz 79

80 Koreanosaurus boseongensis 2.5 m (8 ft) TL, 45 kg (100 lb) Fossil Remains: Partial skeleton. Anatomical Characteristics: Robustly constructed. Legs relatively short. Age: Late Cretaceous, Santonian or Campanian. Distribution: South Korea; Seonso Conglomerate. Habits: Like its closest relatives, likely dug burrows using robust arms. Yueosaurus tiantaiensis 2 m (6.5 ft) TL, 20 kg (45 lb) Fossil Remains: Partial skeleton. Anatomical Characteristics: Standard for hypsilophodonts, but skull is unknown. Age: Early Cretaceous, probably Albian. Distribution: Eastern China; Liangtoutang. Notes: Among the most basal known ornithopods from Asia. ZP Zheng et al. Trinisaura santamartaensis Fossil Remains: Partial skeleton. Age: Late Cretaceous, Campanian. Distribution: Western Antarctica; Snow Hill Island. 80

81 Habitat: Polar forests with warm, day-light dominated summers and cold, dark winters. Notes: May be a basal iguanodontian. The first ornithopod described from Antarctica. Shared its habitat with Antarctopelta. Albertadromeus syntarsus 2 m (6.5 ft) TL, 20 kg (45 lb) Fossil Remains: Partial skeleton. Anatomical Characteristics: Lower leg long and slender. Age: Late Cretaceous, Campanian. Distribution: Alberta; Oldman. Habitat: Well-watered, forested floodplain with coastal swamps and marshes, cool winters. Habits: Well adapted for running. Notes: Closely related to Orodromeus and Zephyrosaurus. Thescelosaurus assiniboiensis Fossil Remains: Minority of skull and partial skeleton. Anatomical Characteristics: Hips relatively small. Age: Late Cretaceous, Late Maastrichtian. Distribution: Saskatchewan; Frenchman. Habitat: Well-watered forest. Notes: Somewhat intermediate between Parksosaurus and Thescelosaurus neglectus; and considerably smaller than both. Iguanodontians Tenontosaurs Rhabdodonts Mochlodon (or Rhabdodon) vorosi Fossil Remains: Minority of skull and skeleton. Age: Late Cretaceous, Early Campanian. Distribution: Austria; Gosau. Habitat: Forested island. Notes: Likely includes some remains assigned M. suessi, which is invalid. Dryosaurs Eousdryosaurus nanohallucis 1.6 m (5 ft) TL, 13 kg (30 lb) Fossil Remains: Partial skeleton. Anatomical Characteristics: Hallux reduced. Age: Late Jurassic, late Kimmeridgian. 81

82 Distribution: Portugal, Alcobaca Habits: Well adapted for running. Notes: A basal dryosaurid. Dysalotosaurus (or Dryosaurus) lettowvorbecki See 283 Notes: Resurrected genus for Dryosaurus lettowvorbecki. Ankylopollexia Camptosaurs Uteodon (or Camptosaurus) aphanoecetes See 285 Notes: New genus for Camptosaurus aphanoecetes. Ankylopollexia Miscellanea Kukufeldia tilgatensis Fossil Remains: Minority of skull. Age: Early Cretaceous, Barremian. Distribution: Southeast England; Weald Clay. Notes: Originally placed in Iguanodon anglicus. Shared its habitat with Baryonyx. Barilium dawsoni See 286 Notes: New genus for Iguanodon dawsonii. Bolong yixianensis Fossil Remains: Partial skull and skeleton. Age: Early Cretaceous, Barremian or Aptian. Distribution: Northeast China; Yixian. Habitat: Well-watered forests and lakes. Notes: Main enemy Yutyrannus. The most primitive iguanodont known from Asia. Cumnoria prestwichii See 285 Notes: New genus for Camptosaurus prestwichii. Found to be a more derived iguanodont than Camptosaurus. Sellacoxa (or Barilium) pauli 8 m (25 ft) TL, 2.5 tonnes Fossil Remains: Partial skeleton. 82

83 Age: Early Cretaceous, Early Valanginian. Distribution: Southeast England; Hastings Beds. Notes: Originally placed in Barilium dawsonii. May still be a species of Barilium. Ratchasimasaurus suranareae Fossil Remains: Minority of skull. Age: Early Cretaceous, Aptian. Distribution: Thailand; Khok Kruat. Notes: Shows a combination of primitive and advanced characteristics. Potential synonymous with Siamodon. Iguanodontoids Iguanodonts Delapparentia turolensis 10 m (35 ft) TL, 6 tonnes Fossil Remains: Partial skeleton. Age: Early Cretaceous, Early Barremian. Distribution: Spain; Camarillas. Notes: Main enemy Camarillasaurus. Dollodon bampingi See 289 Notes: Correct spelling of Dollodon bambingi. Hippodraco scuttodens 4.5 m (15 ft) TL, 400 kg (900 lb) Fossil Remains: Complete skull and partial skeleton. Anatomical Characteristics: Skull subrectangular. Age: Early Cretaceous, Late Barremian or Early Aptian. Distribution: Utah; upper Cedar Mountain. Habitat: Short wet season, otherwise with floodplain prairies, open woodlands, and riverine forests. Habits: Middle-level browser. Notes: Shared its habitat with Iguanacolossus, Eolambia and Animantarx. 83

84 McDonald et al. Hypselospinus fittoni See 288 Notes: New genus for Iguanodon fittoni. Likely includes Huxleysaurus hollingtoniensis. Iguanacolossus fortis 10 m (35 ft) TL, 6 tonnes Fossil Remains: Partial skull and skeleton. Age: Early Cretaceous, Early Barremian. Distribution: Utah; upper Cedar Mountain. Habitat: Short wet season, otherwise with floodplain prairies, open woodlands, and riverine forests. Habits: Middle- and high-level browser. Notes: The largest iguanodont known from North America. Shared its habitat with Hippodraco, Eolambia and Animantarx. McDonald et al. Proa valdearinnoensis 8 m (25 ft) TL, 2.5 tonnes Fossil Remains: Majority of skull and partial skeleton. Anatomical Characteristics: Lower jaw fairly deep, lower beak pointed. Age: Early Cretaceous, Early Albian. Distribution: Spain; Escucha. Habits: Beak well suited for cracking hard objects, such as nuts. Notes: The latest known Early Cretaceous iguanodontoid from Europe. 84

85 Darwinsaurus evolutionis See 288 Notes: New genus and species name for Unnamed genus and species. May include remains assigned to Mantellodon carpenteri. Siamodon nimngami Fossil Remains: Minority of skull. Age: Early Cretaceous, Aptian. Distribution: Thailand; Khok Kruat. Notes: Potentially synonymous with Ratchasimasaurus. Hadrosaurs Baso-Hadrosaurs Zhuchengosaurus maximus See 294 Notes: May be synonymous with Shantungosaurus. Batyrosaurus rozhdestvenskyi Fossil Remains: Partial skull and minority of skeleton. Age: Late Cretaceous, Santonian to Campanian. Distribution: Kazakhstan; Bostobinskaya. Notes: Remains assigned to Arstanosaurus akkurganensis are probably a juvenile of this genus. Huehuecanauhtlus tiquichensis 7 m (23 ft) TL, 2 tonnes Fossil Remains: Minority of skull and partial skeleton. Anatomical Characteristics: Vertebral spines over hips form shallow ridge. Age: Late Cretaceous, Santonian. Distribution: Western Mexico; Barranca Los Bonetes. Notes: One of the best known southerly hadrosaurs. May be an euhadrosaur. 85

86 Ramírez-Velasco et al. Jeyawati rugoculus 6 m (20 ft) TL, 1 tonne Fossil Remains: Partial skull and minority of skeleton. Anatomical Characteristics: Snout elongated and slightly curved down, beak narrow. Wrinkled bone on upper eye socket likely contained excessive blood vessels. Age: Late Cretaceous, Turonian. Distribution: New Mexico; Moreno Hill. Habitat: Coastal swamps and marshes. Habits: Low-level browser and grazer. May have had a display structure above or behind eyes that could be flushed red with excess blood. Notes: Classification as a baso-hadrosaur uncertain, may be a derived iguanodontoid. Shared its habitat with Nothronychus and Zuniceratops. Nanyangosaurus zhugeii 5 m (16 ft) TL, 600 kg (1,200 lb) Fossil Remains: Partial skeleton. Anatomical Characteristics: Hand relatively long. Age: Early Cretaceous, Albian. Distribution: Eastern China; Sangping. Notes: The earliest confirmed hadrosaur. Xuwulong yueluni 4 m (13 ft) TL, 300 kg (650 lb) Fossil Remains: Complete skull and partial skeleton. Anatomical Characteristics: Snout narrow, beak rounded, lower jaw fairly robust. Age: Early Cretaceous, Aptian or Albian. Distribution: Northwest China; Xinminpu. Habits: Middle- and low-level browser. Notes: Main enemy Xiongguanlong. Shared its habitat with Beishanlong and Suzhousaurus. Lapampasaurus cholinoi Fossil Remains: Minority of skeletons. 86

87 Age: Late Cretaceous, Late Campanian or Early Maastrichtian. Distribution: Southern Argentina; lower Allen. Habitat: Semiarid coastline. Notes: Yet to be described in detail, could be synonymous with Willinakaqe. Yunganglong datongensis Fossil Remains: Minority of skull and partial skeleton. Age: Early Late Cretaceous. Distribution: Eastern China; Zhumapu. Notes: Probably includes remains assigned to Bactrosaurus. Gongpoquansaurus mazongshanensis Fossil Remains: Partial skull and skeleton. Anatomical Characteristics: Skull subrectangular, hand short. Age: Early Cretaceous, Albian. Distribution: Central China; Xinminbo Group. Notes: New genus for Probactrosaurus mazongshanensis as has found to be less derived than Probactrosaurus. Some remains may belong to Equijubus. Zhanghenglong yangchengensis 5 m (16 ft) TL, 600 kg (1,200 lb) Fossil Remains: Partial skull and minority of skeleton. Age: Late Cretaceous, Middle Santonian. Distribution: Eastern China; Majiacun. Habits: Likely a mid-level browser. Notes: An advanced non-hadrosaurid hadrosauroid. Probactrosaurus gobiensis See 292 Notes: Probably a moderately derived hadrosaur, close to euhadrosaurs, rather than an iguanodont. Plesiohadros djadokhtaensis 7 m (23 ft) TL, 2 tonnes Fossil Remains: Majority of skull and partial skeleton. Anatomical Characteristics: Skull subtriangular, beak rounded. Age: Late Cretaceous, Campanian. Distribution: Mongolia; Djadokhta. Habitat: Desert with dunes and oases. Habits: Likely a generalist browser and grazer. Notes: Yet to be described in detail. Euhadrosaurs 87

88 Hadrosaurines Acristavus (or Brachylophosaurus) gagslaroni 8 m (26 ft) TL, 3 tonnes Fossil Remains: Majority of skulls and minority of skeleton. Anatomical Characteristics: Beak narrow, squared off. Lacked cranial crest. Age: Late Cretaceous, Campanian. Distribution: Montana, Utah; Two Medicine, Wahweap. Habitat: Seasonally dry woodlands. Habits: Middle- and low-level browser. Notes: Too little is known to determine if the lack of a crest is gender related. Gates ZP Kundurosaurus nagornyi 8.5 m (27 ft) TL, 3 tonnes Fossil Remains: Partial skull and minority of skeleton. Anatomical Characteristics: Snout short. Age: Late Cretaceous, Late Maastrichtian. Distribution: Eastern Russia; Udurchukan. Notes: Appears to be an intermediate between Saurolophus and Edmontosaurus. Shared its habitat with Amurosaurus. Godefroit et al. Latirhinus uitstlani 7.5 m (25 ft) TL, 2.5 tonnes Fossil Remains: Majority of skull and partial skeleton. Anatomical Characteristics: Beak broad, nasal crest well developed. Age: Late Cretaceous, Middle Campanian. 88

89 Distribution: Northeastern Mexico; Cerro del Pueblo. Habits: Low-level browser. Notes: Skeletal characteristics intermediate between hadrosaurines and lambeosaurines. Shared its habitat with Hypacrosaurus and Coahuilaceratops. Willinakaqe salitralensis 9 m (30 ft) TL, 4 tonnes Fossil Remains: Several partial skulls and skeletons, juvenile and adult. Anatomical Characteristics: Snout short, beak squared off, low ridge between nasal openings. Age: Late Cretaceous, Late Campanian and/or Early Maastrichtian. Distribution: Southern Argentina; lower Allen. Habitat: Semiarid coastline. Habits: Likely consumed low lying vegetation. Notes: The southerly hadrosaur known from the most complete remains. Shows strong similarities to North American Kritosaurus. Shared its habitat with Austroraptor and a variety of sauropods. Valieri et al. ZP 89

90 Rhinorex (or Kritosaurus) condrupus 9 m (30 ft) TL, 4 tonnes Fossil Remains: Majority of skull and partial skeleton, skin impressions Anatomical Characteristics: Snout strongly downturned, shallow crest ridge over large nasal openings. Skin covered in small, non-overlapping, roughly hexagonal scales interspersed with occasional, larger, slightly domed scales. Age: Late Cretaceous, Campanian. Distribution: Utah; Neslen. Habitat: Coastal region. Notes: Potentially synonymous with Kritosaurus (or Gryposaurus) monumentensis. Gates and Scheetz ZP Canardia garonnensis 7 m (23 ft) TL, 2.2 tonnes Fossil Remains: Partial skull and minority of skeleton. Age: Late Cretaceous, Late Maastrichtian. Distribution: France; Marnes d Auzas. Notes: Possibly a basal lambeosaurine, along with close relative Aralosaurus. Lambeosaurines Tsintaosaurus sphinorhinus See 308 Anatomical Characteristics: Crest is actually a fan or leaf shaped structure similar to Olorotitan, rather than just a forward projecting tube. 90

91 Prieto-Márquez and Wagner Blasisaurus canudoi 6 m (20 ft) TL, 1 tonne Fossil Remains: Partial skull and skeleton. Age: Late Cretaceous, Late Masstrichtian. Distribution: Spain; Arén. Notes: Potentially synonymous with Arenysaurus, but too little is known to be certain. Kazaklambia convincens Fossil Remains: Partial skull and majority of skeleton, juvenile. Anatomical Characteristics: Standard for juvenile lambeosaurine. Age: Late Cretaceous, Santonian. Distribution: Kazakhstan; Dabrazinskaya Svita. Notes: A basal Hypacrosaurus-type lambeosaurine; originally designated a species of Corythosaurus, and then Procheneosaurus. Procheneosaurus remains, which consist solely of juveniles, are assignable to other Hypacrosaurus-type lambeosaurines, namely Hypacrosaurus and kin in North America and Kazaklambia in Asia. Kazaklambia is the most basal known Hypacrosaurus-type lambeosaurine and may indicate an Asiatic origin for this group. Adelolophus hutchisoni Fossil Remains: Minority of skull. Age: Late Cretaceous, Early Campanian Distribution: Utah; Wahweap. Notes: Earliest known North American lambeosaurine hadrosaur. Shared its habitat with Diabloceratops and Acristavus, main enemy Lythronax. Magnapaulia laticaudus See 314 Fossil Remains: Partial skull and skeleton, skin impressions. 91

92 Anatomical Characteristics: Small non-overlapping roughly hexagonal scales on upper portions of body, slightly larger osteoderm-like scales scattered on tail region. Notes: New genus for Hypacrosaurus laticaudus. Márquez et al. 92