A new species of Euprognatha Stimpson , 1871 ( Crustacea , Brachyura , Inachoididae ) from off coast of northeastern Brazil

A new species of Euprognatha Stimpson, 1871 from off coast of Brazil (Canopus Bank, 02°15.3’00”S 38°16.0’00”W) is described and illustrated, namely Euprognatha limatula n. sp. The new species is compared to its congeners. Lectotypes are designated for E. acuta A. Milne-Edwards, 1880 and E. granulata Faxon, 1893. A key to the species of Euprognatha

are secured and sent to sorting centers for study, much can be learned about the taxonomic composition and endemicity of seamounts communities.After all, it is well known that the discovery of many rare or new species world-wide has been made possible through the collaboration of the fishing industry.Fishing activities recently conducted in the Canopus Bank, off coast of northeastern Brazil, have yielded many interesting crustacean and mollusk specimens (Costa & Simone, 2006;Melo-Filho & Melo, 2006;Simone, 2005;2006;Simone & Abatte, 2005).Among the material sent to the Zoological Museum in São Paulo for study is a new species of spider crab of the genus Euprognatha Stimpson, 1871.The new species is described herein and compared with its congeners.Abbreviations are as follows: cl, carapace length, rostrum included; cw, carapace width; P2-P5, second to fifth pereiopods, P1 is the cheliped.The material herein

InTroduCTIon
Seamounts are common features to all ocean basins and many are subject to intense commercial fisheries world-wide, which results in serious impact to its fauna (e.g., Koslow & Gowlet-Homes, 1998;de Forges et al., 2000;Clark & O'Driscoll, 2003;Morato et al., 2004;Morato et al., 2006).The seamounts contribution to the ocean's biodiversity is likely to be significant and, indeed, a number of them have been documented to present high levels of endemicity (Stocks, 2004).Although there are thousands of seamounts in the world's oceans, only a few have been adequately sampled and studied.While widely regarded as a threat to seamount benthic communities, the fishing trawling fleet can play a role in helping to understand the seamount fauna.When biological material obtained as side catch during fishing cruises  (Rathbun, 1935: 112, pl. 24, figs. 16-19).
Antennal flagella long; third and fourth antennal articles long, slender, exceeding rostrum.First and second antennal articles fused to epistome; second article with long spine in anterolateral angle, slightly directed upward; ventro-lateral margin of second article with row of sub-equal tubercles.
Epistome slightly wider than long.Epistomial spine and interantennular septa separated by small gap.Mouthfield trapezoidal, strongly produced anteriorly.Pterygostomian region subtriangular, with small tubercles, separated from subhepatic region by shallow groove.Subhepatic region with strong tubercle.
Third maxillipeds completely covering buccal frame.Exopod long, nearly reaching distal margin of merus; dorsal face with small, uniformly distributed tubercles.Ischia longer than broad; mesial margins slightly curved, leaving distinct gap; crista dentata with row of short setae and small teeth; dorsal face of ischium concave longitudinally, with small, wellspaced tubercles.Merus faintly longer than half of ischium, ornamented with small, well-spaced tubercles; anterolateral margin strongly expanded.Palp cylindrical, longer than merus; propodus and dactyl unarmed; carpus ornamented with spinules dorsally.
Sternite IV strongly sloping down in ventral view, densely covered with rounded granules.Sternite III broadly triangular, with sparse granules.Sternites V-VIII densely paved with rounded granules.
Chelipeds equals, subcylindrical, distinctly long.Dactyl and fixed finger distinctly shorter than palm, cutting edges consisting of sub-equal calcareous teeth; when closed fingers leaving gap in proximal half; dactyl with small, blunt, distinct basal tooth.Movable and fixed fingers smooth on mesial and lateral faces, inconspicuous carina on lateral face of dactyl.Propodus slender, weakly inflated, with minute, almost imperceptible granules.Carpus with minute granules on mesial and lateral surfaces, almost smooth dorsally.Merus with minute granules.Ischium coarsely granulated.Pereiopods slender, cylindrical.First ambulatory leg longer, remaining legs decreasing in length posteriorly.Dactyl slightly curved, densely setose, small tubercles on lower edge.Carpus with sparse, minute granules on upper and lower surfaces.Merus with dorsal, strong, backward curved spines; smaller spines on lateral and ventral faces; mesial face of pereopods smooth.Ischium with spinules on lateral surface.
Distribution: Known so far only from the type locality.
Etymology: From the Latin limatula (diminutive feminine), polish, scrape, in allusion to the aspect of the chelipeds.
Remarks: Euprognatha limatula n. sp.differs from all its congeners by the (i) presence of distinct, subequal protobranchial and anterior mesobranchial spines (versus protobranchial and anterior mesobranchial spines absent, figs.3-6); (ii) dactyl, propodus, and merus of the cheliped minutely granulated, granules almost imperceptible (versus coarsely granulated, fig.1A); (iii) dactyl of P4 only slightly longer than half of the maximal length of propodus (versus much longer than half of the propodus, almost reaching proximal end of carpus, figs.2B-E); (iv) gastric and cardiac regions of the carapace almost smooth, carapace finely granulated on the flanks (versus carapace coarsely granulated or strongly tuberculated all over, figs.3-6).Additionally, Euprognatha limatula n. sp. is promptly distinguished from E. gracilipes by its second antennal spine much longer than rostrum in dorsal view (versus shorter than rostrum in dorsal view, figs.3B, D); from E. ricei and E. bifida by the absence of intestinal spine (versus one or two strong intestinal spines, respectively, figs.3A, D); and from E. granulata by the meri of P2-P4 armed with sparse, strong, backward curved spines (versus densely distributed, short, straight spines, figs.1B and 2A).Euprognatha limatula n. sp. is further differentiated from E. bifida, E. ricei, and E. gracilipes by its strong interantenular spine (versus interantenular spine absent, fig.1E).

lectotypes designations
Euprognatha acuta A. Milne-Edwards, 1880: The specimens upon which A. Milne-Edwards (1880) based the description of E. acuta were obtained by the steamer "Blake" (Peirce & Patterson, 1879) in Saint Kitts, Grenadines, Saint Vincent, and Barbados.A. Milne-Edwards (1880: 7) did not mention how many individuals were available to him.The "Blake" collections were kept in the MCZ, where three males and one female syntypes of E. acuta are well preserved.They are as follows: one male from Saint Kitts, two males from Saint Vincent, and one female from Barbados (for details see above under comparative material).There is no material of E. acuta from the Grenadines in the MCZ.When available A. Milne-Edwards used to retain a few specimens in the Muséum national d'Histoire naturelle, in Paris.It is then well possible that the material from the Grenadines be housed there.In order to ensure that the name Euprognatha acuta A. Milne Edwards, 1880, be properly and consistently applied, the male MCZ 2580, cl 6.6, cw 5.3 mm, from Saint Vincent, "Blake", station 269, 13°07'55"N -61°05'36"W, A. Agassiz coll., 3.iii.1879,227 m, is selected herein as the lectotype.The second male from Saint Vincent, the male from Saint Kitts (MCZ 2728), and the female from Barbados (MCZ 2600) are the paralectotypes.
Euprognatha granulata Faxon, 1893: Faxon (1893: 149) based the description of E. granulata upon two ovigerous females from Cocos Island, Costa Rica (for details see above under comparative material).Because no holotype was designated and in order to ensure that the name Euprognatha granulata Faxon, 1893, be properly and consistently applied, the female syntype MCZ 4477, cl 7.7, cw 6.0 mm, is selected herein as the lectotype.The second female is the paralectotype.