Five new species of freshwater crabs (Crustacea: Decapoda: Brachyura: Potamidae) from China
Author
Naruse, Tohru
Author
Yeo, Darren C. J.
Author
Zhou, Xianmin
text
Zootaxa
2008
1812
49
68
journal article
10.5281/zenodo.182785
1749a1df-4abd-4559-9fe0-9b7235729c9d
1175-5326
182785
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.
FIGURE 3.
Male gonopods of
Latopotamon xuanweiense
spec. nov.
(paratype male, 21.0×26.2 mm). a, left G1, ventral view; b, distal segment of left G1, vento-outer view; c, distal segment of left G1, dorso-inner view; d, left G2. Scales, 1 mm.
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.
FIGURE 4.
Latopotamon qujingense
spec. nov.
(holotype male, 18.4×23.1 mm). a, habitus, dorsal view; b, cephalothorax, anterior view.
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.
FIGURE 5.
Ventral view of
Latopotamon qujingense
spec. nov.
(holotype male, 18.4×23.1 mm).
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.