PROC. BIOL. SOC. WASH. 107(3), 1994, pp. 465-468 OCCURRENCE OF TWO LITHODID CRABS (CRUSTACEA: DECAPODA: LITHODIDAE) IN THE COLD SEEP ZONE OF THE SOUTH BARBADOS ACCRETIONARY PRISM Enrique Macpherson Abstract.— Two species of lithodid crabs from a cold seep area south of the island of Barbados, Caribbean Sea, are reported. One of the species, Paralomis arethusa, is new, and is described. The other species is Lithodes manningi Macpherson. This is the first report of representatives of this family in areas of emissions of chemically reduced fluids. The discovery of new communities as-sociated with emissions of chemically re-duced fluids has received great attention in the last years (e.g., Jones 1985). These ben-thic assemblages were first discovered at hy-drothermal vents in the Galapagos Ridge (Londsale 1977), and more recently "cold-seep communities" have been found in the Caribbean area (JoUiver et al. 1 990), Oregon (Kulm et al. 1986) and Japan (Laubier et al. 1986), revealing the existence of organisms closely related to those inhabiting hydro-thermal vents. The study of the fauna of these zones has revealed the existence of many new forms exhibiting adaptations of great scientific interest (e.g., Hecker 1985). The decapod crustacean fauna of these ecosystems has been studied by several au-thors (e.g., Williams 1 980, Williams & Chace 1982, Williams & van Dover 1983, Wil-liams & Rona 1986, Guinot 1988, Saint-Laurent 1988, Guinot 1989). The discovery of two species of lithodid crabs, one of them new, in the cold seep community south of Barbados is the first report of this family in these zones. The specimens are deposited in the Mu-seum national d'Histoire naturelle, Paris. Measurements given refer to the length of the carapace, excluding rostrum (CL), and the maximum width of the carapace, ex-cluding the lateral spines (CW). Paralomis arethusa, new species Figs. 1, 2 Material examined.— Holotype, DI API-SUB Expedition, sta DSOl/2, 10°19'64"N, 58°53'42"W, 1691 m, 24 Dec 1992, Female (CL 15 mm, CW 14.5 mm). Description.— Carapace as long as wide, somewhat hexagonal in contour. Dorsal surface of carapace covered with minute granules of various sizes, but without spines. Regions well-defined. Gastric region more prominent than others, with thick granule on apex and 2 thick granules posteriorly, near the gastro-cardiac groove. Cardiac re-gion more prominent than branchial regions. Each branchial region with 1 thick median granule. Rostrum with straight lower median spine slightly directed downwards, smooth ven-trally; with 2 slightly divergent dorsolateral spines. Carapace margins armed with few spines. Postocular spine not overreaching cornea. First anterolateral spine larger than post-ocular. Three or 4 spines of various sizes and several large granules on each branchial edge. Posterior margin smooth. Abdominal segments covered with mi-nute granules. Ocular peduncles with distodorsal spine. First segment of antennal peduncle with 1
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