Thecaplax capillosa sp. nov.

(Figs. 4E, F, 5K, 6E, 34, 35, 41G)

Material examined. Holotype: male (11.6 × 9.5 mm) (MZB Cru 3916), Kecinan, northern Lombok, Indonesia, coll. D.L. Rahayu et al., 15 May 2007 . Paratypes: Indonesia: 3 males (13.5 × 10.8 mm, 13.7 × 10.9 mm, 15.1 × 11.5 mm), 2 females (11.2 × 8.4 mm, 13.4 × 10.4 mm) (ZRC 2013.1712), Kuta, eastern Lombok, coll. D.L. Rahayu et al., 18 August 2006 ; 3 females (7.5 × 5.8 mm, 10.2 × 8.4 mm, 13.6 × 11.4 mm) (NNM), Sira, northern Lombok, coll. D.L. Rahayu et al., 13 June 2007 , intertidal; 1 male (8.9 × 7.8 mm) (NNM), Nara, northern Lombok, 14 June 2007 ; 1 male (13.7 × 10.9 mm), 1 female (14.9 × 11.6 mm) (MZB Cru 3917), 1 male (13.2 × 10.4 mm), 1 female (13.4 × 10.6 mm) (QM), 5 males (7.0 × 5.6 mm –10.7 × 8.6 mm), 5 females (7.7 × 6.3 mm –12.6 × 10.2 mm) (ZRC 2013.1713), 1 female (12.7 × 10.5 mm) (ZRC 2013.1714), Kecinan, northern Lombok, coll. D.L. Rahayu et al., 3 May 2011 .

Diagnosis. As for genus.

Description. Carapace subquadrate; dorsal surface gently convex, distinctly granular, setose; regions separated by deep, distinct grooves (Fig. 34A). Front entire; gently deflexed, margin rounded, with shallow median longitudinal depression, lined with long setae which obscures margin (Fig. 34A). Anterolateral margin arcuate, granular, hirsute; cut into 3 broad, distinct granuliforn lobes, demarcated by deep clefts; separated from posterolateral margins (Fig. 34A). Posterolateral margins almost straight, subparallel (Fig. 34A). Posterior carapace margin gently concave (Fig. 34A). Epistome narrow, partially sunken (Fig. 34C). Basal antennal article transversely rectangular, distinctly wider than long; article 3 rectangular, longer than broad; article 4 distinctly dorsoventrally flattened, twice as long as broad, margins with numerous long plumose setae (Fig. 6E). Basal antennular article subovate; antennules folding almost vertically (Fig. 6E). Eye immobile, completely filling orbit, pear-shaped, tapering towards small, indistinct unpigmented cornea; peduncle stout, tuberculated (Fig. 34C, 35C).

Third maxillipeds relatively short, stout, closing buccal cavern; ischium rectangular, slightly longer than broad, with shallow sublateral sulcus; merus quadrate, about half length of ischium, anterolateral angle rounded; exopod relatively narrow, reaching midlength of merus, with long flagellum (Figs. 5K, 35B).

Chelipeds subequal, long setae on upper, lower margins of chela, carpus, merus; outer surface of chela covered by large tubercles, short setae; dactylus almost as long as palm, with median longitudinal sulcus; cutting margins with distinct teeth, denticles (Fig. 34A, E, F).

Ambulatory legs relatively short; dorsal, ventral margins of ambulatory legs with long setae, outer surface granulated, hirsute; third leg longest; merus of last leg 2.4 times as long as broad; propodus elongated, much longer than broad; dactylus long, longer than propodus (Fig. 34A).

Male thoracic sternum relatively wide; st1, 2 completely fused to form subtriangular plate; st3 separated from st2 by concave suture; st3, 4 medially depressed, st3, 4 visibly separated by shallow but distinct oblique grooves joining at end of sterno-abdominal cavity; sutures 4–7 complete; st8 subrectangular; groove between st7, 8 narrow, reaching cx5; sterno-abdominal cavity deep, reaching to imaginary line joining base of coxae of chelipeds; pressbutton mechanism for holding male abdomen present as small rounded tubercle on anterior third of st5 (Fig. 34B, D).

Male abdomen relatively narrow, a1 very broad, wide medially, tapering laterally to form acutely triangular structure, reaching cx5; a3–5 fused, sutures distinctly visible; a3 expanded laterally to form acutely triangular structure; a6 rectangular, distal lateral sides with low protuberance, straight proximally; telson triangular, broader than long, tip rounded (Figs. 34D, 35A).

Gl stout, slightly sinuous, proximally dilated, distal half more slender than proximal, tip gently tapering, lateral, mesial margin with numerous spinules, outer surface with scattered smaller spinules (Fig. 35D–G). G2 as long as G1, slender, distal segment about 0.6 length of basal segment, slightly more slender than distal segment, tapering at tip (Fig. 35H).

Female chelipeds subequal; outer surface of chelae with tubercles. Female abdomen relatively narrow, 6 free somites, telson (Figs. 4E, 35I); vulvae ovate with distinct operculum (Fig. 4F).

Colour. In life, they are dirty white but stained by mud and appear brown (Fig. 41G).

Etymology. From the Latin capillaris for “hairy;” alluding to the very setose carapace and legs of the type species.

Remarks. In a small female (7.7 × 6.3 mm) and a male (7.0 × 5.6 mm) (ZRC 2013.1713), the surface of the chelipeds has sparser setation and the tubercles on the chelipeds are relatively stronger but less dense.

Distribution. Lombok (Indonesia); intertidal, from sandy areas.