Statommatia granulosa Ng & Castro, 2016, n. sp.
Creators: name: Ng, Peter K. L.
name: Castro, Peter
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Chasmocarcinidae
Statommatia
Statommatia granulosa

description: Statommatia granulosa n. sp.
(Figs. 16 H; 26E; 33F; 45I, J; 55A; 61D; 78C‒G)
Type material. Holotype male (4.1 × 4.7 mm) (MNHN-IU-2013-9454), New Caledonia, Boulari Pass, BATHUS 2, stn DW747, 22°29.87’S, 166°24.17’E, 574 m, 15.05.1993.
Diagnosis. Carapace (Fig. 16 H) subtrapezoidal, conspicuously granular, convex dorsally, 1.1 wider than long; front granular, bilobed, with shallow median cleft; anterolateral margins arcuate, granular, without distinct lobes or teeth. Eye peduncle (Fig. 26 E) granular, filling orbit, short, immobile; cornea reduced, with reduced pigmentation. Posterior margin of epistome (Fig. 26 E) with semicircular median lobe without median fissure, semicircular lateral margins. Third maxilliped (Fig. 33 F) merus subquadrate, ischium subquadrate, about same length as merus. Proportionally long ambulatory legs (Fig. 16 H); P5 merus 0.7 cl. Chelipeds (Figs. 16 H; 45I, J) granular, subequal in length, heteromorphic; fingers of minor chela (Fig. 45 J) subcircular in cross-section, short, scissor-like, cutting margins with distinct teeth; cutting margins of major chela of males (Fig. 45 I) with short teeth, most proximal enlarged. Inner margin of cheliped carpus with short distal tooth (Fig. 16 H). Fused thoracic sternites 1, 2 (Fig. 55 A) semicircular, broad, short. Male pleon (Figs. 55 A; 61D) with proportionally short telson. G1 (Fig. 78 C‒F) stout, distal segment curved inwards, with short to long spinules, apex obtuse. G2 (Fig. 78 G) about 1/2 G1 length, straight, slender. Female unknown.
Remarks. The new species is most similar to S. pubescens (Chen, 1998) in its granular carapace and chelae, but can easily be separated by possessing a third maxilliped in which the anteroexternal angle of the merus is auriculiform (Fig. 33 F) (rounded in S. pubescens, Fig. 33 D), having almost the entire surface of the major chela granular (Fig. 45 I) (with the median part smooth in S. pubescens, Fig. 16 G); and the distal half of the G1 being relatively short, stout, and gently curving upwards (Fig. 78 C–F) (with the distal part conspicuously more slender and distinctly curving laterally in S. pubescens, Fig. 78 A, B).
Statommatia granulosa n. sp. is also similar to S. malagasy n. sp. but the dorsal surface of the carapace and outer surfaces of the chelae are prominently granular (Fig. 45 I, J) (smoother in S. malagasy n. sp., Fig. 45 G, H) and the structure of the G1 is different, with the basal part proportionately much stouter and the distal part relatively shorter (Fig. 78 C, D) (basal part proportionately more slender, and the distal part more elongated in S. malagasy n. sp., Fig. 77 I). The posterior margin of the epistome of the male holotype, the only specimen examined, has no median fissure (Fig. 26 E), which is also an atypical character for the genus.
Distribution. Only known from New Caledonia. Depth: 574 m.
description: Published as part of Ng, Peter K. L. & Castro, Peter, 2016, Revision of the family Chasmocarcinidae Serène, 1964 (Crustacea, Brachyura, Goneplacoidea), pp. 1-182 in Zootaxa 4209 (1) on pages 75-76, DOI: 10.11646/zootaxa.4209.1.1, http://zenodo.org/record/272646