Latopotamon qujingense Naruse, Yeo & Zhou, 2008, spec. nov.
Creators: name: Naruse, Tohru
name: Yeo, Darren C. J.
name: Zhou, Xianmin
Publisher: name: Zenodo
Year: 2008
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Potamidae
Latopotamon
Latopotamon qujingense

description: Latopotamon qujingense spec. nov.
(Figs. 4–6)
Material examined. Holotype: male, 18.4× 23.1 mm, NCU MCP 2008.0003, Fuyuan County (ca. 25°28’ 0 3’’N 103°45’51’’E), Qujing City, Yunnan Province, coll. Guanxian Gu & Xianmin Zhou, 28 Jul. 2005.
Paratypes: 1 male, 16.2× 20.8 mm, 4 females, 9.2×11.5–18.2× 23.7 mm, NCU MCP 2008.0004, data same as holotype; 2 males, 8.6×10.9, 14.3× 18.2 mm, 2 females, 7.7×9.6, 9.3×12.0 mm, ZRC 2008.0014, data same as holotype;
Description. Carapace (Fig. 4 a) broader than long, widest across middle of anterolateral margins, CW 1.25–1.30 times (mean = 1.27, n = 8) CL; dorsal surface almost flat, punctate; epigastric, postorbital cristae low, cervical groove indistinct, H-shaped gastric groove distinct. Front directed antero-ventrally, anterior margin concave medially in dorsal view, bifurcate in anterior view, embracing proepistome. Supra-, infraorbital margins (Fig. 4 b) cristate, lined with low granules, granules on infraorbital margin larger; suborbital, pterygostomial regions weakly rugose. External orbital angle broad, directed anterior-inward, outer margin about 3 times longer than inner margin; epibranchital tooth low but distinct, anterolateral margin convex, lined with rounded granules with irregular gaps. Antennular fossa narrow, oblong; epistome with posterior margin cristate, granulated, with large median triangular tooth.
Palp of mandible three-segmented, with terminal segment simple. Third maxilliped (Figs. 4 b, 5) rectangular, midlength of merus about three-fifths that of ischium, exopod with wide base, reaching proximal third of outer margin of merus, flagellum half width of merus.
Thoracic sternites 2, 3 (Fig. 5) demarcated by distinct suture, suture between sternites 3, 4 indiscernible. Abdominal cavity reaching imaginary line joining posterior ends of cheliped coxae, cavity relatively wide, distance between inner ends of sutures between thoracic sternites 4, 5 more than half length of distance between sternal condyles; sternal condyle placed slightly posterior to middle of thoracic sternite 5; thoracic sternite 8 demarcated medially by uninterrupted longitudinal median line, without transverse ridge at inner ends of sutures between thoracic sternites 7, 8.
Chelipeds subequal in males (Fig. 4 a); merus with granulated dorsal, ventral margins, dorsal granules larger; carpus with strong inner angle, with one inward-directed granules on proximal-ventral part of base of inner angle; palm with moderately convex outer surface, reticulated, length about 1.5 times of height; fingers as long as palm, gape narrow when chela closed, cutting edge lined with low teeth.
Ambulatory legs (Fig. 4 a) short, with scattered short setae, second longest when stretched laterally; anterior margin of meri rough, subdistal angle indistinct, dactyli longer than respective propodi.
Male first abdominal segment with transverse ridge; third segment widest, lateral margins of third to six segments forming almost straight line; telson triangular, width 1.81–1.91 times length (mean =1.86, n = 2), 1.07–1.13 times (mean = 1.10, n = 2) longer than sixth segment, sixth segment width 2.46–2.58 times length (mean = 2.52, n = 2). G1 (Figs. 6 a–c) stout, distally bent dorsal-outward, subdistal segment with produced subproximal outer margin; ventral outer layer of G1 with longitudinal suture along inner margin; distal margin of dorsal side of subterminal segment membrane-like; distal segment directed dorsal-outward by proximal two-thirds, distal third directed outwards, proximal two-thirds of outer margin swollen, distal anterior tip upturned. G2 (Fig. 6 d) as long as G1, flagellum ribbon-like, length about two-thirds of narrowed part of basal segment.
Etymology. The species is named after the type locality, Qujing City, Yunnan Province, China.
Distribution and habitat. Latopotamon qujingense spec. nov. is known only from the type locality (Fuyuan County, Qujing City, Yunnan Province, China; 1913 m asl.). The species was found from under stones in the water with depth of about 25 cm. The water temperature was 18 and the pH was 6.0.
Remarks. The form of the short and stout G1 of Latopotamon qujingense spec. nov. clearly places it in the genus Latopotamon and allies it in particular to the type species, L. obtortum. Latopotamon qujingense can, however, be distinguished from L. obtortum by the shape of the anterolateral margin of the carapace and the G1s. In L. qujingense, the anterolateral margin is serrated by short but sharp granules, the terminal segment of the G1 is narrow and strongly twisted, and the tip of the G1 is directed in a ventral-outer-downwards orientation (Figs. 4, 6 a–c). While in L. obtortum, the anterolateral margin is lined with blunt granules, the G1 is stout and twisted medially, and the tip of the G1 is directed laterally [Dai et al. 1984: Fig. 12, Pl. I (1); Dai & Türkay 1997: Fig. 11 (4, 5), Pl. II (7); Dai 1999: Fig. 235 (6, 7), Pl. 30(4)]. A key to the species of Latopotamon, which now includes three species, is provided below.
description: Published as part of Naruse, Tohru, Yeo, Darren C. J. & Zhou, Xianmin, 2008, Five new species of freshwater crabs (Crustacea: Decapoda: Brachyura: Potamidae) from China, pp. 49-68 in Zootaxa 1812 on pages 52-55, DOI: 10.5281/zenodo.182785