Sundathelphusa vienae Husana, Yamamuro & Ng, 2014, sp. nov.
Creators: name: Husana, Daniel Edison M.
name: Yamamuro, Masumi
name: Ng, Peter K. L.
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Gecarcinucidae
Sundathelphusa
Sundathelphusa vienae

description: Sundathelphusa vienae sp. nov.
(Figs. 4–6, 7 C, D)
Material examined. Holotype: male (21.3 × 17.9 mm) (NMCR 39077), Nilulubugan Cave, Atimonan, Quezon Province, Luzon, Philippines, 14˚ 01.000N, 121˚ 47.775E, coll. D.E.M. Husana, December 2009. Paratype: 1 female (19.8 × 16.5 mm) (NSMT-Cr 22317).
Description. Carapace distinctively quadrate (Fig. 4 A), widest at anterior quarter, broader than long, dorsal surface convex longitudinally, dorso-ventrally inflated, regions distinct; branchial regions covered with distinct oblique striae; cervical groove prominent; H-shaped gastric groove distinct. Epigastric cristae distinct, edges sharp, separated by distinct median furrow; postorbital cristae, sharp; epigastric, postorbital cristae, not confluent; epibranchial teeth, postorbital cristae not confluent. Frontal margin (Figs. 4 B, 5C) protruded, gently sinuous, deflexed. External orbital tooth triangular, produced anteriorly; outer margin convex, longer than inner margin; epibranchial tooth distinct, small, well separated from external orbital tooth by notch; anterolateral margin convex, armed with small granules, clearly demarcated from posterolateral margin; posterolateral margin almost straight to gently concave, with oblique striae converging gradually towards posterior margin of carapace. Frontal median triangle (Figs. 4 B, 5C) distinct but not complete, with protruded dorsal margin; orbit well demarcated; supraorbital margin smooth; infraorbital margin beaded with distinct granules; outer edge reaching, fused with anterolateral margin; suborbital, subbranchial regions covered with few scattered oblique striae of various sizes; pterygostomial region with streak of oblique ridges on upper part. Posterior margin of epistome (Figs. 4 B, 5D) with 3 lobes, median lobe, triangular; lateral lobes wider, distal margin more protruded anteriorly.
Eyes well developed (Fig. 4 B), occupying almost entire orbit. Third maxilliped ischium (Fig. 6 A) rectangular, much longer than broad, bearing distinct oblique submedian sulcus closer to mesial margin; merus quadrate, distalexternal angle convex, upswept; tip of exopod not reaching midpoint of outer margin of merus, with flagellum reaching beyond edge of mesial margin of merus.
Chelipeds not noticeably elongated, subequal, stronger in males; margins of merus serrated, dorsal margin with small subdistal tooth; carpus armed with strong distal sharply pointed inner tooth, dorso-ventrally flattened; palm with smooth outer surface; fingers robust, cutting edges armed with medium-sized to large sharp teeth.
Ambulatory legs (Figs. 4 A, 5B) long, slender, second leg longest, anterior margins of meri distinctly serrated, without subdistal tooth or spine, posterior margins smooth on all legs; second, third pair shorter than carapace length; carpi short, with longitudinal submedian ridge on dorsal surface, widened distally; propodi, dactyli subequal in length.
Male abdominal cavity reaching level of proximal quarter of coxae of chelipeds. Male abdomen (Figs. 5 A, 6B) narrow, T-shaped; somite 1 short, somite 6 longer than broad; proximal, distal margins of somites 3–5 sinuous; lateral margins of somite 2 convex; lateral margins of somite 3 convex; lateral margins of somite 4 straight, narrows gradually to distal end; somites 3–5 narrow gradually; lateral margins of somite 5 concave, proximally wide distally narrow; lateral margins of somite 6 straight; telson subtriangular, broader than long, lateral margin slightly concave medially, rounded distally. G1 (Figs. 5 E, F, H, I) slender, slightly bent outwards; subterminal segment gradually tapering towards terminal segment, segments separated by distinct suture; terminal segment straight, tapering, cylindrical. G2 (Figs. 5 G, J) subequal in length to G1, flagellum short.
Female. Female chelipeds subequal, neither inflated; abdomen ovate, covering entire thoracic sternum, all somites and telson freely articulating; telson broadly triangular with convex lateral margins (Fig. 7 C). Vulvae large, subovate, without operculum; on median part of somite 6 (Fig. 7 D).
Coloration. Dorsal surface of carapace is brownish to orange in life, chelipeds are yellowish to orange.
Etymology. Named after a daughter of the first author, Vien Danille Husana, who accompanied him in some of his fieldwork.
Remarks. Sundathelphusa vienae sp. nov. is unusual among Sundathelphusa species in that it has a relatively high carapace like S. picta (von Martens, 1868) and its allies. The new species, however, has a more quadrate carapace and proportionately longer ambulatory legs in contrast to the more ovate inflated carapace and shorter legs of the latter (cf. Bott 1970: pl. 12 figs. 36–38). The G1 is also more slender than in S. picta and almost straight, with its tapering pointed terminal segment (Figs. 5 E, F, H, I; versus Bott 1970: pl. 28 fig. 50).
description: Published as part of Husana, Daniel Edison M., Yamamuro, Masumi & Ng, Peter K. L., 2014, Two new species of freshwater crabs of the genus Sundathelphusa Bott, 1969 (Decapoda: Brachyura: Gecarcinucidae) from caves in Luzon, Philippines, pp. 565-574 in Zootaxa 3815 (4) on pages 569-572, DOI: 10.11646/zootaxa.3815.4.6, http://zenodo.org/record/230822