A new species of the deep-sea genus Bresilia (Crustacea: Decapoda: Bresiliidae) discovered from a shallow-water cave in Madeira

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1 J. Mar. Biol. Ass. U.K. (2004), 84,191^199 Printed in the United Kingdom A new species of the deep-sea genus Bresilia (Crustacea: Decapoda: Bresiliidae) discovered from a shallow-water cave in Madeira Ricardo Calado* Ð,PierreChevaldonne O and Antonina dos Santos P *Laborato rio Mar timo da Guia^IMAR, Estrada do Guincho, Cascais, Portugal. O UMR DIMAR, Centre d Oce anologie de Marseille, Station Marine d 0 Endoume, Rue Batterie des Lions, Marseille, France. P Instituto de Nacional de Investigac a o Agra ria e das Pescas, Av. de Bras lia, s/n Lisboa, Portugal. Ð Corresponding author, rjcalado@hotmail.com During a recent survey of the biodiversity of shallow-water aphotic marine caves of Madeira Island (north-east Atlantic), 12 specimens of the rare deep-sea shrimp genus Bresilia (Caridea: Bresiliidae) were collected from a depth of 15 m. The collected shrimps are described and illustrated as Bresilia saldanhai sp. nov., increasing to ve known species of the genus. Morphological characters are compared and discussed, and an updated world key for the genus Bresilia is presented. For the rst time, a species of this poorly known genus can be described from a signi cant number of intact specimens. This occurrence once more demonstrates the strong environmental similarities and evolutionary ties between marine caves and the deep sea. INTRODUCTION Dark marine caves of the littoral zone and deep-sea rocky habitats display remarkably similar environmental conditions, such as the absence of light, depleted food availability, and sometimes constant low temperatures (Hart et al., 1985; Harmelin et al., 1985; Harmelin, 1997). Faunal a nities have been found indicating that in many instances, caves and other shallow cryptic habitats, may be considered as refugia or extensions of the deep aphotic system in the littoral zone (Harmelin et al., 1985). Caves are like natural laboratories presenting unique opportunities for researchers to easily access organisms and processes otherwise very di cult to sample and understand. North-eastern Atlantic Macaronesian islands are of particular interest to understand the biogeographical ties existing between Mediterranean and Atlantic faunas. With the objective of better understanding the relationships between the relatively well-studied Mediterranean cave communities and those of Madeira (Portugal), a survey of Madeiran shallow-water caves was conducted during the year One of the most striking results of this biodiversity survey was the chance discovery of a new species of the deep-sea genus Bresilia Calman, This genus was previously represented by only four species whose known distribution, depth range and habitat are reported in Table 1. It is remarkable that each of these four species occurs in relatively deep waters and is very poorly known. Bresilia atlantica Calman, 1896, for which the family Bresiliidae was created, was originally described from a single specimen dredged o Ireland (Calman, 1896). Four additional specimens were later recovered from the same area (Kemp, 1910). Bresilia corsicana Forest & Cals, 1977 is currently known from a single Mediterranean specimen (Forest & Cals, 1977). The other two, Bresilia plumifera Bruce, 1990, and Bresilia antipodarum Bruce, 1990, are Australian species also described from single specimens (Bruce, 1990a,b). Interestingly, the new species of Bresilia from Madeira is known from a dozen specimens, and its population can be conveniently sampled by cave divers in only 15 m depth, providing opportunities to better understand the biology, ecology and phylogenetic relationships of this rare and debated group of caridean shrimps. MATERIALS AND METHODS Specimens were collected by SCUBA diving using a hand-held collection bottle and were stored in 80% ethanol. Drawings and measurements were made with a camera lucida on a Wild M8 dissecting stereomicroscope, and on a Zeiss microscope for. Canada balsam and Faure s liquid were used in the preparation of slides of appendages. Setal counts refer to a proximal-to-distal sequence. Total length (TL) was measured from the tip of the rostrum to the posterior end of the telson. Carapace length (CL) was measured from the posterior orbital margin to the posterior margin of carapace. The described specimens have been deposited in the Museu Municipal do Funchal in Madeira, Portugal (MMF34416^MMF34420). SYSTEMATICS Order DECAPODA Latreille, 1802 Suborder PLEOCYEMATA Burkenroad, 1963 Family BRESILIIDAE Calman, 1896 Genus Bresilia Calman, 1896 Bresilia saldanhai sp. nov. (Figures 1^4) Type material Holotype: adult female 2.58 mm CL (10.24 mm TL; 1.54 mm rostrum; 2.22 mm rst pereiopod chela length; 1.64 mm second pereiopod chela length) [MMF34416].

2 192 R. Calado et al. A new bresiliid shrimp from a Madeiran cave Table 1. World distribution, depth range and habitat of the ve Bresilia species. B. atlantica (Calman, 1896; Kemp, 1910) B. antipodarum (Bruce, 1990a) B. corsicana (Forest & Cals, 1977) B. plumifera (Bruce, 1990b) B. saldanhai sp. nov. (present study) World distribution Eastern Atlantic, south of Ireland Western Paci c, Tasman Sea, Eastern Tasmania Western Mediterranean, Corsica Channel Western Paci c, Tasman Sea, Taupo Seamount Depth range 1229 to 1372 m 800 m 450 m 133 m 15 m Habitat Unknown Over coarse shelly Among Madrepora Unknown sand oculata Eastern Atlantic, Garajau Cave, Madeira Island Close to the cave walls; near the wall/ oor interface Figure 1. Bresilia saldanhai, sp. nov., female holotype, 2.58 mm CL. Lateral view. Scale bar: 1 mm. Paratypes: four adult males (1.19^1.57 mm CL; 5.31^ 5.50 mm TL) [MMF34417 and 34418], two adult females with eggs (2.31^2.58 mm CL; 8.82^10.24 mm TL) [MMF34419], one juvenile (1.00 mm CL; 4.31mm TL) [MMF34420]. Four additional adult specimens have been dedicated to molecular studies: three were males (1.22^2.19 mm CL, 4.8^7.7 mm TL) and one was of undetermined sex (damaged; 1.95 mm CL, 7.4 mm TL). All specimens have been collected by SCUBA diving by one of us (P.C.) in an underwater cave at Ponta Garajau, south of Madeira Island, Eastern Atlantic (32.638N W), water depth: 15 m, 26 September Diagnosis Bresilia saldanhai displays all the morphological characters used by Vereshchaka (1997) for the diagnosis of the family Bresiliidae: rostrum denticulate, exopods well developed in maxilliped 3 and the rst two pairs of pereiopods; epipods absent from pereiopods; arthrobranchs absent; and appendix interna well developed in pleopods 2^4. Description of adult female A small slenderly built shrimp, of subcylindrical, slightly compressed body form, bright red in vivo. Carapace smooth and glabrous. Rostrum slender, straight and acute, well developed, tip reaching to about level of distal margin of second of antennular peduncle; dorsal carina thin, extending feebly onto carapace, with 10^13 small acute dorsal teeth, the rst one being posterior to the posterior orbital margin. Ventral margin with 1^2 small acute sub-distal teeth. Antennal and pterygostomial spines present, the latter more acute. Inferior orbital angle acute. Ventral margin of carapace presenting an in exion near the second pereiopods. Eye with rounded, pigmented cornea, reaching to about middle of rostral length. Corneal diameter about 20^22% of CL. Abdomen smooth, third strongly produced postero-dorsally. Pleura of rst three s large, broadly rounded, fourth small with posteroventral extension with an acute spine and another small one on the lateral posterior margin. Pleura of fth almost convex with two teeth in the posterior end. Sixth compressed with posterior border almost straight. Telson about 1.2^1.3 of CL, and 0.6^0.8 of sixth abdominal length, slightly shorter than uropods, rather straight and slender, with lateral margins feebly convergent proximally, more strongly convergent for distal 2/3^3/4, with 6^7 pairs of small submarginal dorsal spines on distal 2/3^3/4; posterior margin roundly truncated, about 1/3 of anterior margin width, displaying three pairs of non-setulose spines, lateral posterior spines about the size of dorsal spines, intermediate spines large, robust, 3^4 times longer than dorsal spines, submedian spines 1.5^2 times longer than dorsal spines. Antennule with proximal of peduncle broad, stylocerite broad, acute, not reaching distal margin of

3 A new bresiliid shrimp from a Madeiran cave R. Calado et al. 193 Figure 2. Bresilia saldanhai, sp. nov., female holotype. (A) Anterior portion of thorax, lateral detail; (B) antennule; (C) antenna, ventral view; (D) mandible; (E) maxilulla; (F) maxilla; (G) telson; (H) left uropod. Scale bars: A, B, H, 1 mm; C^G, 0.1 mm.

4 194 R. Calado et al. A new bresiliid shrimp from a Madeiran cave Figure 3. Bresilia saldanhai, sp. nov., female holotype. (A) First maxilliped; (B) second maxilliped; (C) third maxilliped; (D) rst pereiopod; (E) second pereiopod; (F) fth pereiopod. Scale bars: A^D, 0.1 mm; E^F, 0.5 mm.

5 A new bresiliid shrimp from a Madeiran cave R. Calado et al. 195 Figure 4. Bresilia saldanhai, sp. nov. (A) First pleopod of female holotype; (B) rst pleopod of male paratype; (C) second pleopod of male paratype; (D) second pleopod of female holotype. Scale bars: A, B, D, 0.5 mm; C, 0.1 mm., medial border setose, with small ventral tooth, statocyst obsolete; second and third s almost the same size. Inner agellum with 34 small articles and the outer agellum almost twice the size of the endopod. Antenna with the two proximal articles robust, the second one with large distal dorsolateral tooth and strong ventrolateral tooth, third and fourth s small, the latter presenting a long plumose seta, the fth being much longer with 9^15 in the distal margin. Scaphocerite large, far exceeding the antennular peduncle, broadly rounded distally, lateral margin straight, with well-developed distal tooth, not exceeding distal margin of lamella. Flagellum very long, six times the scaphocerite length and with three small on the distal end. Epistome with long slender acute median process projected forward. Labrum large. Paragnaths developed, alae with transverse conical lobes. Mandible small, feebly calci ed, with palp well developed, 2-ed, proximal subcylindrical, with one seta on distal margin, distal subequal to proximal length, attened, with four long and one short setulose marginal and ve pairs of subdistal short ; molar process reduced, laminar, tapering to distal point; incisor process broader, distally tapered to 7^9 acute teeth, with preterminal tubercle on dorsal margin. Maxillula with slender, curved palp, with two unequal, pre-terminal ; upper lacinia broad, with 14^16 stout, dentate marginal spines, largest ve ventral marginal, with submarginal row of six more slender serrulate spines and proximal row of seven slender serrulate spines; lower lacinia slender, with four long setulose on ventral margin, and six pairs of long stout spines along the dorsal margin. Maxilla with elongate palp, styliform, with one seta on distal end; basal endite bilobed, distal lobe subcircular with 14 marginal setulose and nine sub-marginal ones, proximal lobe more elongate, with 11 marginal setulose and seven sub-marginal ones; coxal endite simple with nine marginal setulose and ve submarginal ones; scaphognathite well developed, more than three times longer than wide, with 72, 11 of them very long and on the posterior margin. First maxilliped with small simple palp, with six plumose distomedially and a small one on the posterior end; basal endite small, broad with 27 sparsely setulose, exopod with caridean lobe, with 17 sparsely plumose marginal, agellum slender, with several short plumose distally; epipod bilobed, elongate and narrow. Second maxilliped with endopod stout, dactylar terminal, distally rounded, with 16 long serrulate

6 196 R. Calado et al. A new bresiliid shrimp from a Madeiran cave Table 2. Comparative presentation of morphological characters of the ve Bresilia species. B. atlantica (Calman, 1896; Kemp, 1910) B. antipodarum (Bruce, 1990a) B. corsicana (Forest & Cals, 1977) B. plumifera (Bruce, 1990b) B. saldanhai sp. nov. (present study) Rostrum Branchiostegite Antennule Antenna Cornea Mandibles First maxilliped exopod Third maxilliped endopod Pointing up; nearly reaching the distal end of the second of antennular peduncle; 3^ 4 teeth on upper margin (the rst just behind the orbit); 2^7 teeth on the lower margin Obtusely angulated above the base of the rst pereiopods Stylocerite very large, reaching to distal margin of Ischiocerite without Devoid of pigment; faint traces of facets without Without agellum Without plumose on antepenultimate First pereiopod chela Posteroventral margin unarmed Second pereiopod chela Third abdominal Fourth abdominal Fifth abdominal Telson posterior margin Size of studied specimens (TL) Tipped with minute tufts of Strongly gibbous, but not produced posterodorsally; not carinated with 1 small tooth with 1 small tooth Roundly truncated Slightly pointing down; reaching to about level of distal margin of proximal of antennular peduncle; upper margin with 9 small acute teeth, all posterior to orbital margin; lower margin with one very small acute tooth Very acute, with intervening margin deeply concave Stylocerite very large, reaching to distal margin of Ischiocerite without Devoid of pigment; without facets without Presenting a well developed agellum n.a. Posteroventral margin with three transverse rows of short cleaning Tipped with minute tufts of Strongly produced posterodorsally, with conspicuous blunt, triangular, median carina Pleura broadly rounded, with very small posteroventral tooth Pleura bluntly subrectangular, with small posteroventral tooth Angulate, with central portion slightly produced and with small median point Slightly pointing down; barely reaching the proximal end of the second of antennular peduncle; 10 acute teeth on upper margin (the rst just above the orbit); 1 distal toothonlower margin Obtusely angulated above the base of the third pereiopods Stylocerite broad, acute, not reaching distal margin of, with a spineinthe external face Ischiocerite without Well pigmented; facets present without Without agellum Without plumose on antepenultimate Posteroventral margin with four transverse rows of short stout plumose Tipped with a nail and minute tufts of Not produced posterodorsally; not carinated produced; angular; with 1 small tooth with 2 small teeth Straight; not reaching the distal end of the rst of antennular peduncle; upper margin with 4 small acute teeth ( rst tooth proximal to posterior orbital margin; lower margin unarmed) Anterior margin deeply convex Stylocerite broad, acute, not reaching distal margin of Ischiocerite bearing Well pigmented without Presenting a slender agellum With plumose on antepenultimate Posteroventral margin with three transverse rows of short serrulated spines, with single larger stout simple spine n.a. Strongly produced posterodorsally with medium carina produced; rounded with 1 small tooth Straight, slender and acute, well developed, tip reaching to about level of distal margin of second of antennular peduncle; dorsal carina thin, extending feebly onto carapace, with 10^13 small acute dorsal teeth, the rst one posterior to posterior orbital margin Obtusely angulated above the base of the third pereiopods Stylocerite broad, acute, not reaching distal margin of Ischiocerite bearing Well pigmented; facets present with 1 seta Presenting a slender agellum Without plumose on antepenultimate Posteroventral margin with two transverse rows of short, with single larger stout simple spine Tipped with minute tufts of Strongly produced posterodorsally; not carinated produced; angular; with 1 small tooth with 2 small teeth With median notch n.a. Roundly truncated 17^29mm 14.5mm 15mm 6mm 4.3^10.24mm n.a., information not available; TL, total length.

7 A new bresiliid shrimp from a Madeiran cave R. Calado et al. 197 marginal spines and eight similar sub-marginal spines; propod longer than wide, with seven sparsely distributed ; carpus short, unarmed; ischiomerus longer than wide with four spines medially; basis subequal to ischiomeral length with ve sparsely distributed, exopod longer and slender with plumose distally; coxa medially rounded, with reduced rounded epipod laterally. Third maxilliped with long slender endopod; proximal longer than the two distal ones, all sparsely setose; exopod well developed, slender, reaching the end of the proximal endopod, with plumose distally; basis short, with medially small plumose ; coxa robust with medially small plumose and, small globular epipod dorsolaterally. Thoracic sternites narrow, rst to fourth unarmed, fth with submedian pair of large divergent triangular teeth, sixth and seventh with slender pairs of acute subparallel teeth, eighth with blunt median process, feebly dilated and attened distoventrally. First pereiopod robust, presenting well developed chela; palm smooth, distodorsal margin with small acute tooth, proximal ventral margin with two transverse rows of short serrulate ; ngers strongly de exed; dactyl lightly exceeding xed nger, with slightly upturned blunt tip, dorsal margin convex, carinate, smooth, ventrolateral margin straight, strongly dentate, largest centrally, decreasing strongly in size distally; xed nger deeply concave dorsolaterally, cutting edge straight, with series of deep fossae laterally for reception of dactylar teeth, medially with a row of stout simple teeth; carpus short, stout, slightly expanded, excavate distally, with small dorsal lobe with single short stout simple spine, small ventral lobe with strong simple spine; merus unarmed; ischium obliquely articulated with merus, tapering feebly ventrally with small distally; basis short, stout, exopod well developed, reaching the end of merus, with numerous plumose distally; coxa normal, with rounded dorsolateral protuberance. Second pereiopod well developed, slender, distinctly exceeding rst pereiopod chela, palm subcylindrical, smooth, with three small teeth median dorsally situated; dactylus tapering distally to small feebly hooked terminal spine, with adjacent dense tuft of, cutting edge median, distally directed, with 20 teeth distally increasing in size; xed nger similar; carpus long, subcylindrical; merus sub-cylindrical with six small spines on ventral margin; ischium obliquely articulated with merus, feebly compressed with three small spines along ventral margin; basis with short exopod, not reaching distal margin of ischium, with plumose distal ; coxa without special features. Third and fourth pereiopods well developed, long, slender; dactyl with dorsal margin convex, ventral margin straight, with ve movable spines and one distal xed tooth; propod long, 4.5 times longer than dactyl, with three on distal margin of the third pereiopod and one seta on the fourth; carpus and merus unarmed; ischium with one spine sub-distally on dorsal margin. Fifth pereiopod long, slender; dactyl with dorsal margin convex, ventral margin straight, with four xed teeth, tip with one hooked terminal spine, with adjacent dense tuft of ; propod long, 4.5 times longer than dactyl, with ve small spines along dorsal margin; carpus and merus unarmed, merus longer than carpus; ischium with one spine sub-distally on dorsal margin. Pleurobranchs present on rst four pereiopods only, decreasing in size anteriorly. First pleopod basipodite with numerous plumose marginal ; endopod with small appendix interna; exopod almost twice as long as endopod, both with numerous plumose distal ; other pleopods with endopod slightly smaller than exopod. Appendix masculina reaching the end of endopod with one strong terminal spine, and two pairs of medio-distal spines. Uropods with short protopodite; exopod subequal to telson length, broad, with straight lateral margin, exhibiting a small acute distolateral tooth and with numerous plumose marginal on internal margin; endopod only a little smaller than exopod, lance-shaped, with numerous plumose marginal. Etymology This species is named after the late Professor Luiz Saldanha in recognition of his enthusiastic dedication to studies on the fauna of aphotic marine caves of Madeira Island and Portugal. Habitat and ecology All 12 specimens of Bresilia saldanhai sp. nov. were captured from a cave at Ponta do Garajau, Madeira as a by-catch of a cave mysid (Hemimysis maderensis Ledoyer, 1989) sample. The shrimps were found in a totally dark chamber of the cave, at a depth of 15 m, where very little water movement is supposed to occur. They were found to live very close to the cave walls, as well as near the wall/ oor interface. In that particular part of the cave, the oor is made of extremely ne silty sediment. Associated mobile crustaceans in this part of the cave include the decapods Plesionika narval ( J.C. Fabricius, 1787), Cinetorhynchus rigens (Gordon, 1936), Stenopus spinosus Risso, 1827, Lysmata grabhami (Gordon, 1935), Stenorhynchus lanceolatus (Brulle, 1837), and Dardanus calidus (Risso, 1827). The cave is relatively long and large compared to most of the other caves visited in Madeira, but could only be explored over the rst 20^30 m from the entrance. It has two entrances, both relatively small and leading to a marked upward step. Such a step is likely to strongly attenuate the e ects of outside currents and wave action. Although several other caves have been explored and sampled in Madeira during the same expedition, B. saldanhai sp. nov., was found only at Garajau cave. DISCUSSION Morphological remarks The main morphological di erences among the ve Bresilia species are summarized in Table 2. From this table, it appears that there is no unique conspicuous morphological character in B. saldanhai, but rather a unique combination of characters present in the other species of this genus. Indeed, we cannot be sure of the importance and signi cance of a feature such as the existence of a single seta on the proximal of the mandibular palp. Although the new species is geographically closer to Bresilia atlantica and Bresilia corsicana,

8 198 R. Calado et al. A new bresiliid shrimp from a Madeiran cave B. saldanhai also shares several morphological features with the Australian species, such as the chela of the rst pereiopod, which is very similar to that of B. plumifera, but also the shape of the third abdominal and the presence of a agellum on the exopod of the rst maxilliped, which are also more similar to the Australian species. On the other hand, like B. atlantica and B. corsicana, the new species presents an obtusely angulated branchiostegite above the base of the pereiopods and an angular pleura on the fth abdominal. Bresilia saldanhai also displays some of the particular features of both B. atlantica (such as the roundly truncated posterior margin of the telson) and B. corsicana (such as the obtusely angulated branchiostegite above the base of the third pair of pereiopods). In Bruce s opinion (1990b), the presence of a agellum on the exopod of the rst maxilliped of both Australian species, a character shared with Encantada spinoculata Wicksten, 1989, a bresilioid shrimp of uncertain a nities, could mean that they belonged to a di erent genus than the European species. The morphology of B. saldanhai, however, seems to indicate that this particular feature can either be present or absent within the genus Bresilia. In many respects, the new species seems to be intermediate in its morphology between the two other sets of species, and its discovery clearly warrants the design of a new key. According to the diagnostic key presented by Bruce (1990b), B. saldanhai would be grouped together with the Australian species due to the presence of the agellum on the exopod of the rst maxilliped and to the posterodorsally produced third abdominal. Nevertheless, the new species does not present the typical median carina on the third abdominal as Bresilia plumifera and Bresilia antipodarum. An updated world key is presented below for the convenient identi cation of the ve Bresilia species known so far. Key for the genus Bresilia 1. Cornea devoid of pigments; antennule stylocerite slender,longerthandistalmarginof:... 2 ö Cornea well pigmented; antennule stylocerite broad, notreachingdistalmarginof: Exopod of rst maxilliped without agellum; posterior margin of telson roundly truncated:...b. atlantica ö Exopod of rst maxilliped with agellum; posterior margin of telson angulate with small median point:...b. antipodarum 3. Pleura of fourth abdominal rounded, without tooth; pleura of fth abdominal angular with onesmalltooth:...b. plumifera ö Pleura of fourth abdominal angular with one small tooth; pleura of fth abdominal angular with two small teeth: Exopod of rst maxilliped without agellum; posterior margin of telson with median notch:.... B. corsicana ö Exopod of rst maxilliped with agellum; posterior margin of telson roundly truncated:......b. saldanhai sp. nov. Sexual system In the present study, all smaller specimens displayed male morphological characters while all larger specimens displayed female characters. Although gonochorism is the general rule among decapod crustaceans, protandry is not uncommon, particularly in caridean shrimps (e.g. Bauer, 2000). Kensley (1988) suggested the existence of protandrous hermaphroditism in the hippolytid cave shrimp Yagerocaris cozumel Kensley, 1988 that presents the same sex ^ size distribution as B. saldanhai. The possible occurrence of protandrous or simultaneous hermaphroditism in cave species presents several reproductive advantages, namely the larger size of breeding females (and the consequent larger number of eggs) and the increase in gamete exchange in a restricted gene pool (such as a cave population) (Kensley, 1988; Bauer, 2000). However, with only 12 individuals available, it is not possible to de nitely establish the type of sexual system in this species. Biogeographical and ecological remarks More than a century after Calman 1896 s description of the genus Bresilia, its biology and ecology remain virtually unknown. The main reason for this lack of knowledge is the low catchability of the shrimp due to its small size, depth range and likely cryptic habits (e.g. B. corsicana was collected among Madrepora oculata, B. saldanhai in a marine cave). The mobile fauna of deep rocky substrates is indeed among the most di cult to sample. Most certainly, the years to come, with the technical improvements in SCUBA and deep-sea sampling, will bring further new Bresilia species to science, and ll the zoogeographical gaps within this widely distributed genus (Table 1). The connections between cave and deep-sea faunas are limited by several factors. One of the most severe limitations is the species dispersal abilities (e.g. Harmelin, 1997). The existence of a population of this genus readily accessible to scienti c divers in the Garajau cave will be a unique opportunity to understand the dispersal ability of this genus through the study of its reproductive biology (sexual system, egg production and larval development). Taxonomical remarks The higher classi cation of caridean shrimps and especially the validity of the superfamily Bresilioidea Calman, 1896, erected by Holthuis (1955) has long been debated by several authors (e.g. Holthuis, 1955; Forest, 1977; Christo ersen, 1990; Segonzac et al., 1993; Vereshchaka, 1997; Shank et al., 1999; Martin & Davis, 2001). The latest classi cation of the Recent Crustacea proposed by Martin & Davis (2001) recognizes ve families in this superfamily (Agostocarididae Hart & Manning, 1986, Alvinocarididae Christo ersen, 1986, Bresiliidae Calman, 1896, Disciadidae Rathbun, 1902 and Mirocarididae Vereshchaka, 1997), and more recently Komai & Segonzac (2003) have justi ably synonymized Mirocarididae with Alvinocarididae. However, none of these authors have addressed the phylogenetic relationships of this group. Concerning Bresilioidea, this classi cation follows almost exactly that of Vereshchaka (1997) except for the Agostocarididae, synonymized with

9 A new bresiliid shrimp from a Madeiran cave R. Calado et al. 199 Bresiliidae by the latter author. However, according to these recent classi cations, Bresilia (and in some opinion Agostocaris) now seems to be the only genus left in the family Bresiliidae, whether or not the superfamily Bresilioidea is conserved (Christo ersen, 1990; Vereshchaka, 1997; Martin & Davis, 2001). However, the genera Encantada Wicksten, 1989, and Kirnasia Burukovsky, 1988, have been described only incompletely and have therefore been excluded from most recent attempts to revise the Bresilioidea (Christo ersen, 1990; Vereshchaka, 1997; Martin & Davis, 2001). The advent of molecular techniques in systematics is particularly helpful in studies of di cult groups, such as bresilioid shrimps, in avoiding the pitfalls of purely morphological studies based on species di cult to obtain, and that may display signi cant morphological changes throughout their development. Molecular taxonomic studies exist for bresilioid shrimps, but Shank et al. (1999) have only worked with hydrothermal-vent and cold-seep taxa (i.e. Alvinocarididae). So far, due to their scarcity, no Bresiliidae (sensu stricto) has ever been available for such studies. For the rst time, biological material from this poorly known family and genus is now available for molecular analysis, and the phylogenetic relationships among the bresilioid shrimps may become clearer (work in progress). We express our gratitude to N. Boury-Esnault, A.J. Almeida, M.J. Biscoito, J.-G. Harmelin, J. Vacelet, H. Zibrowius, R. Arau jo, P. Fonseca and L. Costa for diving assistance and collaborative work. Thanks are also due to A.J. Bruce, M. Segonzac and two anonymous referees for comments on the manuscript. This research was supported by the French and Portuguese Governments through cooperation project no. 456 N1. 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