On New Species Of Leucosiidae (Crustacea: Decapoda: Brachyura) From Singapore And The South China Sea
Author
H. - L., Chen
Author
Ng, Peter K. L.
text
Raffles Bulletin of Zoology
2003
51
1
61
69
journal article
10.5281/zenodo.4619317
2345-7600
4619317
Leucosia singaporensis
,
new species
(
Figs. 1G, H
,
5
)
Material examined. –
Holotype
- male (28.0 by 24.0 mm) (
ZRC
1965.10.13.49),
Singapore
, coll.
13 Oct.1965
.
Paratype
–
1 female
(32.0 by
26.3 mm
) (
ZRC
1965.10.13.50), same data as holotype
.
Diagnosis. –
Carapace rhomboidal, smooth (except dorsum which may be pitted); regions indistinct. Hepatic region weakly elevated, median portion very convex. Front slightly projected, with 3 teeth: median tooth longer than weak lateral teeth. Behind front, median line with longitudinal smooth ridge, lateral areas depressed. Anterolateral margin shorter than posterolateral margin, without granules, latter with fine granules. Posterior carapace margin convex medially, both sides slightly convex. Exopod of third maxilliped narrow, 3 times as long as broad; merus narrowly triangular, longer than ischium, female ischium with tooth subdistally, inner side with longitudinal row of setae which extends to base of merus, male ischium without tooth, glabrous. Male abdomen with 5 free segments; segments 3-5 fused, basal half with shallow median groove, both sides strongly convex, median part of distal half convex, sides depressed; segment 1 very narrow transversely; segment 2 very narrow transversely, segment 6 1.4 times as long as broad, median part of basal one-third with small dent; telson triangular. Female abdomen longitudinally ovate, elevated medially, with 4 free segments (segments 3-6 fused), median portion of segments 1 and 2 convex posteriorly; telson slightly longer than broad, distal end bluntly rounded. G1 stout, long, distal part broadly membranous, surrounded by long setae, with hook-like process curving inwards.
Fig. 5.
Leucosia singaporensis
,
new species
. A, B, D, H-J, holotype male (28.0 by 24.0 mm) (ZRC); C, E-G, K, paratype female (32.0 by 26.3 mm) (ZRC). A, carapace; B, right cheliped; C, third and fourth ambulatory legs (top to bottom); D, thoracic sinus; E, third maxillipeds; F, female abdomen; G, female telson; H, male abdomen; I, G1; J, distal part of G1; K, female genital opening. Scales = 0.5 mm.
Etymology. –
The species is named after its
type
locality,
Singapore
.
Remarks. –
This new species closely resembles
Leucosia magna
Tyndale-Biscoe & George, 1962
, and
Leucosia major
,
new species
, in the shape of the carapace and form of the thoracic sinus. The differences between these three species are summarised in Table 1.