The Alpheid Shrimp Genus Leptalpheus Williams, 1965, In The Tropical Western Pacific, With Descriptions Of Two New Species (Crustacea: Decapoda: Caridea) Anker, Arthur Marin, Ivan N. Raffles Bulletin of Zoology 2009 2009-02-28 57 1 91 107 85TJJ Anker & Marin, 2009 Anker & Marin 2009 [918,1188,379,403] Malacostraca Alpheidae Leptalpheus GBIF Animalia Decapoda 9 100 Arthropoda species dworschaki sp. nov.  ( Figs. 9–12)   Leptalpheussp. 7 aff. pacificus– Anker et al, 2006: Table 1.    Type material.–   Philippines: Holotype: male, CL 7.7, TL 21.9 ( NMCR 27540), Panglao Island, Sungcolan Bay, Sta. M11, 9°38.3'N 123°49.6'E, intertidal flat, fringed with mangrove and seagrass, bait suction pump, from burrow of  Glypturussp., coll. P. C. Dworschak,  7 Jun.2004[fcn PD-37; specimen dissected].  Paratype: 1 female, CL 7.7, TL 23.9 ( ZRC 2005.0085), same collection data as for holotype [fcn PD-36].    Description.–Body not particularly slender or stout ( Fig. 10a), carapace and abdomen slightly compressed laterally, glabrous. Carapace with inconspicuous suture proximal to base of antenna ( Fig. 9b, c). Frontal margin protruding and broadly rounded, without rostral projection or orbital teeth, without orbital crests ( Fig. 9a, b, k). Pterygostomial angle rounded ( Fig. 9c); branchiostegial region with pronounced “lip” anteriorly; cardiac notch fairly deep ( Figs. 9c, 10a). Eyes not visible in dorsal view, anterior portion visible in lateral view ( Fig. 9a, c); anteromesial process feebly marked; cornea small, lateral, pigmented. Ocellar beak not conspicuous. Antennular peduncle relatively stout, flattened dorsoventrally; second segment about twice as long as broad, about as long as dorsally visible portion of first segment; stylocerite not reaching distal margin of first segment, subacute distally ( Fig. 9a, b, k); ventromesial carina of first segment with strong tooth ( Fig. 9d); lateral flagellum biramous, with shorter ramus well developed, situated at third segment. Antenna with basicerite bearing strong ventrolateral tooth ( Fig. 9b); scaphocerite broadly ovate, anterior margin of blade convex but not protruding beyond distolateral tooth ( Fig. 9a); carpocerite long, stout, reaching far beyond scaphocerite. Mouthparts and third maxilliped as in previous species ( Fig. 10b–h; for description see above). Chelipeds strongly asymmetrical in shape, unequal in size ( Figs. 11, 12a, b), carried folded when not in use ( Fig. 10a). Major cheliped (on either left or right side) enlarged, elongate ( Fig. 11); ischium short, ventromesial margin without subtriangular tooth; merus long, slender, with smooth margins, distally not widening, ventrally flattened, distally more depressed, distal margin with blunt lobes; carpus short, cup-shaped, with blunt distal process; chela subcylindrical, palm smooth, ventromesially excavated, about 2.5 times as long as high ( Fig. 11c); adhesive discs well developed ( Fig. 11b, c); fingers about 1/3 length of palm; dactylus moderately curved distally, with subacute tip, cutting edge with one median subtriangular-rounded tooth, about 1/2 as high as long, without proximal tooth; pollex shorter than dactylus, abruptly ending, with one blunt terminal tooth, cutting edge with two teeth: one much larger subtriangular proximal tooth and one smaller truncate distal tooth ( Fig. 11c, d). Minor cheliped shorter and weaker than major cheliped ( Fig. 12a); ischium short, unarmed; merus slender, ventrally depressed; carpus very short, cup-shaped; chela smooth, subcylindrical, with fingers about 1.2 times as long as palm, tips crossing when chela closed; cutting edges of dactylus and pollex with small curved teeth proximally and two larger opposing teeth at about mid-length ( Fig. 12b).  Fig. 7.  Leptalpheus denticulatus, new species(a, b), male from Panglao, Philippines (ZRC 2005.0086): a, frontal region, dorsal view; b, major (left) cheliped, carpus and chela, lateral view.  Leptalpheus pacificus Banner & Banner, 1974(c–h), female from Hawaii (USNM 205907): c, major (right) cheliped, ventrolateral view; d, same, detail of fingers; breeding female from Hawaii (FLMNH UF Arthropoda 12473): e, frontal region, dorsal view; f, second pereiopod, lateral view; g, right uropod and telson, dorsolateral view, setae omitted; h, left uropod, detail of protopod. Scale bars: a–g = 1 mm; h = 0.5 mm. Second pereiopod slender; ischium about 3/4 length of merus; carpus five-segmented, segments with ratio approximately equal to: 4/1/1/1/2.5 ( Fig. 12c); chela simple, about as long as first carpal segment; fingers as long as palm. Third pereiopod moderately slender ( Fig. 12d); ischium unarmed; merus flattened mesially, about 2.5 times as long as ischium, about five times as long as wide; carpus less than 1/2 length of merus, with distoventral spiniform seta; propodus longer than carpus, with three ventral spiniform setae and one distoventral spinifom seta proximal to dactylus; dactylus simple, conical, about 2/5 length of propodus, curved ( Fig. 12d). Fourth pereiopod ( Fig. 12e) generally similar to third. Fifth pereiopod ( Fig. 12f) much more slender than third and fourth pereiopods; ischium and merus not flattened mesially, unarmed; carpus without distal spiniform seta; propodus as long as merus, without spiniform setae, distally with at least seven rows of setae; dactylus similar to that of third and fourth pereiopods. First to fifth pleomeres with minute pits on surface; posteroventral angles rounded; sixth pleonite with large articulated plate posteroventrally ( Fig. 10a). First pleopod woth very short endopod, latter fringed with setae apically ( Fig. 9f). Male second pleopod ( Fig. 9g) with appendix interna and appendix masculina, latter almost twice as long as former, and bearing numerous slender, spiniform apical and subapical setae ( Fig. 9h). Uropod with lateral lobe of protopod bearing two small acute teeth distally ( Fig. 9i); endopod somewhat longer than exopod, without specific features; exopod with truncate posterior margin and without distinct distolateral tooth adjacent to distolateral spine; lateral portion of diaeresis straight, not curved into tooth centrally; mesial portion deeply incised forming large triangular tooth proximal to mesial margin ( Fig. 9i). Telson moderately slender, more than twice as long as wide proximally ( Fig. 9j); dorsal surface pitted, with two pairs of robust spiniform setae inserted at short distance from lateral margin, at about 1/3 and 2/3 length of telson, respectively; posterior margin feebly rounded, posterolateral angles each with pair of spiniform setae, mesial at least four times as long as lateral; anal tubercles small, feebly sclerotised. Gill/exopod formula as in previous species (see above).   Colour pattern.–Field notes indicated: “Translucent, slightly pink, ovary green”.   Size. –The CL of both specimens is 7.7 mm; the TL ranges from 21.9 mmin the male holotypeto 23.9 mmin the female paratype.    Etymology. –The new species is named after Peter C. Dworschak (Naturhistorisches Museum in Wien, Vienna, Austria), the collector of the present specimens, our estimated friend and colleague, and also a well known specialist of the Thalassinidea.      Typelocality.– Panglao Island, southwest of Bohol, the Philippines.    Ecology. –Both specimens were collected from a  Glypturuscf. armatusburrow, together with gastropods ( Phenacolepadidae) and sentinel crabs,  Macrophthalmussp. (Ocypodidae)[field notes by P. C. Dworschak].    Distribution. –Western Pacific: presently known only from the typelocality in the Philippines.    Remarks. – Leptalpheus dworschaki, new species, is closely related to  L. pacificusand the above-described  L. denticulatus, new species, but can be separated from both species by the armature on the major chela fingers, in particular by the presence of a distinct blunt tooth on the dactylus (absent in  L. pacificusand  L. denticulatus, new species, although larger individuals may have a broad bulge at the same position); the absence of a small proximal tooth on the dactylus (present in  L. pacificusand  L. denticulatus, new species); and the shorter hiatus between the larger proximal and smaller distal teeth on the pollex (this hiatus is almost twice as long in  L. pacificusand  L. denticulatus, new species) (compare Figs. 11c, dand Figs. 3c, d; 4 b, c; 7c, d).  Leptalpheus dworschaki, new species, can be also separated from  L. denticulatus, new species, by the absence of a small tooth on the central portion of the uropodal diaeresis. We were unable to find any other obvious morphological differences between  L. dworschaki, new species, and  L. pacificusand  L. denticulatus, new species.  Fig. 8.  Leptalpheus denticulatus, new species, colour pattern in life: a, non-type male from Yaqara Bay, Viti Levu, Fiji (MNHN- Na 15776); b, large female paratype from Nhatrang Bay, Vietnam (MNHN-Na 17065), major (left) cheliped detached (photograph by O. Savinkin).  Fig. 9.  Leptalpheus dworschaki, new species, male holotype (NMCR 27540): a, frontal region, dorsal view; b, same, lateral view; c, frontal margin of carapace, lateral view; d, first segment of right antennular peduncle, lateral view; e, lateral flagellum of right antennule, lateral view; f, first pleopod, mesial view; g, second pleopod, mesial view; h, same, appendix masculina and appendix interna; i, right uropod, dorsal view; j, telson, dorsal view; female paratype (ZRC 2005.0085): k, frontal margin, dorsal view. Scale bars = 1 mm.  Fig. 10.  Leptalpheus dworschaki, new species, female paratype (ZRC 2005.0085): a, habitus; male holotype (NMCR 27540): b, mandible, mesial view; c, same, dorsolateral view; d, maxillule, lateral view; e, maxilla, lateral view; f, first maxilliped, lateral view; g, second maxilliped, lateral view; h, third maxilliped, lateral view. Scale bar = 1 mm. The length of the second segment of the antennular peduncle and the shape of the frontal margin appear to be somewhat variable in both  L. dworschaki, new species( Fig. 9a, k), and  L. denticulatus, new species( Figs. 1a, 5a); the latter species is also variable in the proportions of the merus of the third pereiopod ( Figs. 2i, 6h; see also above). Therefore, these features cannot be reliably used to distinguish  L. dworschaki, new speciesfrom  L. denticulatus, new species, or from  L. pacificus. 2004-06-07 NMCR Sta. M & P. C. Dworschak Philippines 9.638333 Panglao Island 129 123.82667 Sungcolan Bay 9 100 NMCR 27540 1 holotype 2004-06-07 ZRC Sta. M & P. C. Dworschak Philippines 9.638333 Panglao Island 129 123.82667 Sungcolan Bay 9 100 ZRC 2005.0085 1 1 paratype Philippines Panglao Island 11 102 1 Bohol holotype