FIG. l.-ho lotype of Dendrobates sirensis, NHMW 31892, SVL = 16.8 mm.

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1 FIG. l.-ho lotype of Dendrobates sirensis, NHMW 31892, SVL = 16.8 mm.

HERPETOLOGICA VOL. 47 MARCH 1991 NO.1 Herpetologica, 47(1), 1991, 1-5 1991by The Herpetologists League, Inc.

2 HERPETOLOGICA VOL. 47 MARCH 1991 NO.1 Herpetologica, 47(1), 1991, by The Herpetologists League, Inc. A NEW SPECIES OF POISON-DART FROG (ANURA: DENDROBATIDAE) FROM THE SERRANiA DE SIRA, PERU MANFRED AICHINGER Zoologisches lnstitut, Univ ersitiit Wien, Althanstraj3e 14, A-1090 Wien, Austria ABSTRACT: A new species of poison-dart frog, Dendrobates sirens is, is described from the Serrania de Sira, an isolated mountain range in east-central Peru, Departamento Huanuco, at an elevation from m. Adult specimens have a snout-vent length of mm. The species is easily diagnosed from all dendrobatids by the uniform red coloration of the dorsum and the turquoise-green limbs. Key words: Anura; Dendrobatidae; Dendrobates sirensis; Peru THE Serrania de Sira is an isolated mountain range in the upper Amazon basin between the Rio Pachitea and the Rio Ucayali in east-central Peru. The highest elevations are about m (Terborgh and Weske, 1975). For an approximate location of this mountain range, see Duellman and Toft (1979). Our expedition followed the same route to the Serrania de Sira as described by Terborgh and Weske (1975). Duellman and Toft (1979) first reported on a collection of anurans from this region, including the dendrobatids Col ostethus marchesianus, Phyllobates (now Epipedobates) petersi, and P. (now Epipedobates) pictus. During a herpetological survey from September 1987 to October 1988, five specimens of the poison-dart frog were captured. This new species was collected first in the Serrania de Sira in 1976 by Werner Hanagarth. METHODS Nineteen different measurements (to the nearest 0.1 mm) were made following Myers (1982). The condition of the om oster- num was judged by dissection. Specimens are deposited in Naturhistorisches Museum Wien (NHMW) and Museo de Historia Natural "Javier Prado" in Lima (MHNJP). One paratype is in the collection of Staatliches Museum fiir Naturkunde Stuttgart (SMNS). Museum abbreviations follow Frost (1985). Dendrobates sirensis sp. nov. Fig. I-Frontispiece Holotype.-NHMW (Fig. 1), an adult female, collected on a horizontal tree 1.2 m above a stream in the Serrania de Sira, Rio Llullapichis drainage, 750 m, Departamento Huanuco, Peru (9 28' S, 74 47' W), on 10 September 1987, at 0910 h by M. Aichinger. Paratypes.-MHNJP and MHN JP 11519, adult males, same location as holotype, 780 m, on the ground, on 20 March 1988, at 1530 h and at 1250 m, in September 1988, both by B. Wallnofer, SMNS 07092, adult male, same location, at 1560 m, on the ground, on 23 January 1976, by W. Hanagarth. 1

2 HERPETOLOGICA [Vol. 47, No.1 Diagnosis.-A very small dendrobatid having an adult snout-vent length (SVL) of about 15-17 mm (three males 14.7-15.4 mm, 1 female 16.8 mm).

3 2 HERPETOLOGICA [Vol. 47, No.1 Diagnosis.-A very small dendrobatid having an adult snout-vent length (SVL) of about mm (three males mm, 1 female 16.8 mm). Skin on back slightly granular, moderately granular on venter, and smooth on limbs; dorsum uniform dark red, arms and legs turquoisegreen, venter turquoise-green with a rectangular red patch on the belly, chin red; neither spots nor reticulation present dorsally; teeth absent; first finger much shorter than second; finger discs very conspicuous, enlarged to at least twice finger width; omosternum absent; tympanum visibly concealed posterodorsally. D. sirensis is tentatively assigned to the quinquevittatus group as characterized by Schulte (1981), Myers (1982), and Zimmermann and Zimmermann (1988). It differs from all members of this group (D. captivus, D. fantasticus, D. imitator, D. mysteriosus, D. quinquevittatus, D. reticulatus, D. vanzolinii, D. variabilis) by its uniform red dorsum, its unreticulated feet and venter, and its turquoise-green limbs. Dendrobates sirensis may be confused with other small poison-dart frogs of the genus Dendrobates or Minyobates, like D. granuliferus, D. pumilio, D. speciosus, M. opisthomelas, and M. steyermarki, which all have a bright red dorsal coloration. Dendrobates sirensis differs from D. speciosus, M. opisthomelas, and M. steyermarki in having turquoise-green limbs, from D. granuliferus in having only a slightly granular skin, and from D. pumilio in having a rectangular red patch on the turquoise-green belly. Description.-Size small, SVL of adults mm; (three males mm; one female 16.8 mm): head narrower than body; in all specimens, greatest head width 32-34% of SVL. Males lacking vocal slits and vocal sacs. Teeth absent, omosternum absent. Skin on the back is slightly granular in life, moderately granular on venter, and smooth on limbs. Snout subtruncate in dorsal aspect and sloping in lateral aspect (Fig. 2). Naris situated near tip of the snout and directed laterally; both nares visible from front and from below but not from above. Canthus rostralis rounded; loreal region more or less flat. Interorbital area wider than upper eyelid. Center of naris to edge of eye/eye length = Tympanum seemingly vertically elliptical, but concealed posterodorsally; its approximated diameter 56-64% of the eye length. Hand relatively large (Fig. 3); its length (proximal edge of metacarpal tubercle to tip of longest finger) 78-87% of greatest head width; relative length of adpressed fingers 3 > 4 > 2 > 1; adpressed first finger roughly three-fourths the length of second finger. Discs conspicuously expanded on all but first finger. Disc of third finger 2 2% times wider than distal end of adjacent phalanx; widths of discs without apparent sexual dimorphism. A circular metacarpal tubercle at base of palm, a smaller inner metacarpal tubercle at base of first finger, and one or two usually prominent subarticular tubercles on fingers (one each on fingers 1, 2, 4, two on finger 3). Distal subarticular tubercle on finger 3 small and inconspicuous, but all other tubercles on hand prominently raised; surfaces of discs rounded; lack of pigment contributing to prominent appearance of tubercles. Hind limbs of moderate length, with heel of adpressed limb reaching tympanum. Tibia 36-39% of SVL. Relative length of adpressed toes 4 > 5 > 3 > 2 > 1; first toe short, reaching bottom of subarticular tubercle on base of second toe, and with unexpanded disc; other toes with discs distinctly expanded (but smaller than finger discs). Moderate-sized inner and small outer metatarsal tubercles, somewhat protuberant but with rounded surfaces. One to three subarticular tubercles (slightly protuberant tubercles, one each on toes 1, 2, two each on 3, 5; nonprotuberant tubercles, one each on toes 3, 5, three on toe 3). Hands and feet lack webbing, supernumerary tubercles, or a lateral fringe (Fig. 3). Measurements (in mm) of holotype. The holotype is a female containing two mature ovarian eggs in both ovaries. Measurements of paratypes are given in Table l. Length from snout-vent 16.8; tibia length from heel to fold of skin on knee 6.4; greatest head width (between angles of jaws) 5.4; head width at level of eyes

March 1991] HERPETOLOGICA 3 o I 5m m F IG. 3.-Palma r and plantar surfaces of right hand and foot of holotype of Dendrobates sire nsis, N H MW 3 1892. o 5mm FI G. 2.

4 March 1991] HERPETOLOGICA 3 o I 5m m F IG. 3.-Palma r and plantar surfaces of right hand and foot of holotype of Dendrobates sire nsis, N H MW o 5mm FI G. 2.- Dorsal and lat er al view of the hea d of th e holotype of Dendroba tes sirensis, NHMW ;approximate width of interorbital area 2.1; head length from tip of snout to angle of jaw 4.0; tip of snout to center of naris 0.8; center of naris to anterior corner of eye 1.5; distance between center of nares 2.0; eye length from anterior to posterior corner 1.8; approximated horizontal diameter of tympanum because tympanum posteriorl y indistinct 1.0 ; corner of mouth to lower edge of tympanic rin g 0.6. Length from pr oximal edge of large medial palmar tubercle to tip of longest (third) finger 4.7; width of third finger di sc 1.1; width of third finger (pe n ultimate phalanx) below disc 0.5. Width of di sc of third toe 0.7; width of third toe proximal to d isc 0.5; width of disc of fourth toe 1.0; width of fourth toe (penultimate phalanx) pr oximal to disc 0.5. Coloration in life.-head and dorsum dark red, no di stinct spots or stripes ; tympanum dark brown; iris black. Arms and legs turquoise-gr een; turquoise colora tion lighter on th e ante rodorsal side of proxim al half of upper arm and in groin anteroventrally on proxim al part of th igh extending onto th e bod y. Venter turquoise-green with a rect an gular red pat ch on th e bell y (appr oxim at ely 5 x 3 mrn): chin dark red ; ve nter below rectangular pat ch and th e ventral sur faces of th e legs dark turquoise. Surfaces of palms and soles black. Parat ype MHNJP had an indistinct brown spot in th e interorbital area. One individual which esca ped from captivit y (sex unknown) showed a di sposition of a rather wide, ill-defin ed red lat er al stripe exte nding horizontally fr om th e groin one -third of the dorsum to th e head (M. Henzl, personal com m unica tion). A color transparency of this specimen suggests that this stripe is not homologous with th e incomplet e oblique lat eral lin e that ch ar acterizes many dendrobatids. In preservative, th e red coloration appears pale gray; turquoise changes to black. The red colora tion of par at ype MHNJP cha nged to black. Parat ype SMNS became pale brown but th e coloration in life was as described above (W. Hanagarth, per sonal com m un ica tion). Life history notes.-the holot ype con tained two we ll-develope d eggs in both ovaries (diameter 2.0, 2.1 mrn) as we ll as

4 HERPETOLOGICA [Vol. 47, No.1 T ABLE I.-Measurements (in mm) from paratypes. MHNJP MHNJP SMNS 11518 11519 7092 Characteristic Male Male Male Length from snout to vent 14.7 14.8 15.

5 4 HERPETOLOGICA [Vol. 47, No.1 T ABLE I.-Measurements (in mm) from paratypes. MHNJP MHNJP SMNS Characteristic Male Male Male Length from snout to vent Tibia length from heel to fold of skin on knee Tibia/SVL 36.1% 39.2% 39.0% Greatest head width (between angles of jaws) Head width/svl Head width at level of eyes Width of interorbital area Head length from tip of snout to angle of jaw Tip of snout to center of naris Center of naris to anterior corner of eye Distance between center of nares Eye length from anterior to posterior corner Naris-edge of eye/eye length 75.0% 85.7% 100.0% Horizontal diameter of tympanum (posteriorly indistinct) Diameter tympanum/eye length 56.3% 64.3% 64.3% Corner of mouth to lower edge tympanic ring Length from proximal edge of large medial palmar tubercle to tip of longest (3rd) finger Length hand/greatest head width 78.0% 83.3% 83.0% Width of third finger disc Width of third finger (penultimate phalanx proximal to disc) Third finger disc /width 3rd finger Width of disc of third toe Width of third toe (penultimate phalanx) below disc Width of disc of fourth toe Width of fourth toe below disc three small eggs (diameter < 1 mm). An un preserved female laid a single egg on the surface of a leaf in a plastic box a few days after capture (M. Henzl, personal communication). Individuals are very agile, jumping continuously. The species seems to be extremely rare or secretive. During one year of investigation, only five individuals were observed (two escaped from captivity). Etymology.-The species is named after the type locality, the Serrania de Sira. DISCUSSION Dendrobates sirensis is known only from the Serrania de Sira in east-central Peru at an elevation from m and seems to be endemic in this isolated mountain range. There it lives in sympatry with D. quinquevittatus, which was found from the lowland rainforest at 260 m up to 1080 m. Based on characters that were attributed to the genus by Silverstone (1975), the new species is assigned to Dendrobates. These characters are first finger shorter than the second, well expanded finger discs, and a bright coloration in life. Dendrobates sirensis may be highly arboreal, judging from the relatively long hand with the well developed discs. One individual showed an indication of light red lateral stripes. A female contained only two mature ovarian eggs. Considering these facts, D. sirensis is tentatively assigned to the D. quinqueoittatus group. Based on characteristic behavioral parameters, Zimmermann and Zimmermann (1988) attributed the following characters to the quinquevittatus group: the arboreal frogs live in middle to upper strata in tropical rainforest; females lay only few eggs; males carry one or two tadpoles to bromeliads; larvae feed facultatively on unfertilized eggs laid by the female. Schulte (1981), Myers (1982), and Zimmermann and Zimmermann (1988) placed the following eight species in the quinquevittatus group: D. captivus, D. fantasticus, D. imitator, D. mysteriosus, D.

March 1991] H ER PETO LO GI CA 5 quinqueoittaius, D. reticulatus, D. vanzolinii, and D. variabilis. Myers (198 2) could not document a relationship of D. captivus and D.

6 March 1991] H ER PETO LO GI CA 5 quinqueoittaius, D. reticulatus, D. vanzolinii, and D. variabilis. Myers (198 2) could not document a relationship of D. captivus and D. mysteriosus to th e quinquevittatus group and left th em as possible close relatives to th at group. Dendrobat es quinquevittatus is widespread throughout the Ama zon Basin, inhabiting primarily lowland rainforest (Le scure and Bechter, 1981; Silverstone, 1975). All othe r species of the quinquevittatus group occ ur onl y in compa ra tively small ar eas in th e western Amazonian lowl ands (Kne lle r, 1983; Myers, 1982 ; Schulte, 1986; Zimmermann and Zimmermann, 1984, 1988). Dendrobates captivus, D. imitator, and D. mysteriosus may be restricted to single localities in montane rainfor est. Except for D. mysteriosus, which is known only from a single spec imen (Myers, 1982), D. quinquevittatus lives sym patrically with all other spe cies. Like Minyobates abditus and M. ste y ermarki, which Myer s and Daly (1976) assigned to th e minutus group as defin ed by Silverstone (1975), and M. opisthomelas, Dendrobat es sirensis might be a terminal relict of an ancestor whose range wa s fragment ed by climatic vegetational change s that occur red in th e Andes during Quaternar y time. F urthe r studies on skin alkaloids, knowledge of tadpoles, and th e reproductive biology of this species will be necessar y to define th e exact ge ne ric and group relationships of D. sirensis. R ESUM E N Se describe Dendrobat es siren sis, una nueva especie de batracio ven en oso de la Serrania de Sira, Departamento Huanuco, Peru, a una elevacion de 750 a 1560 m. Es una rana diminuta (15-17 mm) que se puede facil distinguir de otros dendrobatidos por su color acion. La coloracion dorsal del cuerpo es roja y la de las extre m i dades, verde turqui. data. I am indebted to A. Schliiter (Stuttgart) and N. Carillo (Li m a ) for the loan of specimens. Thanks are also du e to M. H enzl, W. Hodl, K.-H. Jungf er, A. Schliite r, and E. Zimmermann for ca re fullv review ing th e m anuscript and to th e Direccion Ge'ner al Foresta l y de Fauna for permits ( AG-DGFF DR FF-SDFF). F ina ncial support was de rived from "os terreichische r Fonds zur Fiirderung der wissenschaftlichen Forschung" (project P6399B) and "Bundesm ini ster iu m Iur W issensc haft und Forschung, osterreich". LIT E RATURE CITED D UELLMA:-I, W. E., AND C. A. TOFT Anurans fro m the Serrania de Sira, Amazonian Peru: T axonomy an d biogeography. H er pet ologica 35 : F HOST, D. R Am phibian Species of the W orld. Allen Pr ess an d th e Associati on of Syste matics Co l lecti on s, Lawrence, Kansas. KNELLER, M Beobachtungen an Dendrobates fantast icus im na tiirlichen Lebensraum un d im Terrarium. Herpetofauna 5 : LESCURE, J., Al':D R. BECHTER Le comportement de reproduction en captivite et Ie pol ymorph isme de Dendrobates quinquevit tatus Steindachner. Revu e fro Aq ua rio!. 8: MYERS, C. W Spotted poison frogs: Description of three new Dendrobates from western Amazonia, and resurrecti on of a lost species from "Chiriq ui". Am. Mu s. Nov it :1-23. MYEHS, C. W., ANDJ. W. DALY A ne w species of poison fr og (Dendrobates) fr om Ande an Ecu a dor including an ana lysis of its skin toxins. Occ. Pa p. Mu s. Nat. H ist. Un iv. Kan sas 59:1-12. SCHULTE, R Dendrobat es qui nqueoittat us ; iikologie, Haltung und Zucht. Herpet ofauna 3: Eine neu e Den drobates-art aus Ostpe ru (Am phibia ; Salientia; Den drobatidae ). Sauria 8: SILVERSTONE, P. A A revision of th e poisondart fro gs of th e ge nus Dendrobat es W agler. Nat. Hi st. Mu s. Los Angeles Co. Sci. Bull. 21:1-53. T EHBORGH, J., ANDJ. S. W ESKE The role of competit ion in th e distributi on of Andean bird s. Ec ology 56: ZIMMERMANN, H., AND E. ZIMMERMANI': D ur ch Nachzucht er ha lten: Baumsteigerfriische Dendrobat es quinqu evittatus und D. reticula tus. Aq u. Mag. 18: Etho- Taxon om ie und zoogeograph ische Artengruppenbild ung bei Pfeilgift friischen (Anur a: Dendrobatidae ). Salamandra 24 : Accepted: 26 Ap ril 1990 Associate Editor: David Cannate lla Acknowledgments.-I thank B, W allnofer for collecting specim ens an d M. Henzl for obse rva tional

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