Grapsodes Heller 1865

Genus Grapsodes Heller, 1865 Grapsodes Heller, 1865: 58. — Kingsley 1880: 188, 197. — Alcock 1900: 440 (key p. 441). Mystacocarcinus Hilgendorf, 1888: 26-29. Epigrapsus (Grapsodes) Sendler, 1923: 27. Epigrapsus — Tesch 1918: 132 pro parte. — Türkay 1974a: 248 pro parte. — Ng et al. 1998: 71; 2000: 379 pro parte. — Fujita 2017a: 20, only. — Hartnoll et al. 2017: 939, fig. 3. — Naruse et al. 2018: 208 pro parte. TYPE SPECIES. — Grapsodes notatus Heller, 1865. DIAGNOSIS Carapace squarish to distinctly wider than long, transversally ovate (larger specimens). Females with more quadrate carapaces. Dorsal surface gently convex to strongly convex, with fairly distinct grooves on large specimens; epigastric cristae prominent and sharp in small specimens, weak and rounded in much larger specimens. In males, tufts of short black setae in small and medium-sized individuals, lost in larger individuals, resulting in a glabrous surface. Anterolateral margins gently convex to strongly arcuate (larger specimens); with three teeth: one external orbital tooth and two epibranchial teeth, variously developed and variably arranged, depending on the size. Posterolateral margins subparallel to more or less converging towards posterior carapace margin (larger specimens). Fronto-orbital border more than half width of carapace. Front entire, deflexed, with two developed inner subfrontal lobes; outer lobes shorter. Antennules folded tranversely; basal article exposed, squarish; article 2 small, only partly visible. Antenna with basal article (2 + 3) squarish; article 4 almost invisible; flagellum bent downwards in orbital hiatus. Proepistome small, dome-shaped; encircled by developed inner frontal lobes. Orbit only basally delimitated, sheltering proximal part of podophtalmite; a pointed tooth at inner angle. External orbital tooth acutely triangular, distinctly separated from anterolateral margin by small but distinct cleft; first epibranchial tooth small but distinct; second epibranchial tooth often low or almost undiscernible (more prominent in smaller specimens). Suborbital margin entire, subparallel to frontal margin, not connected to orbit, inner margin with very low tooth, outer edge ending abruptly. Suborbital ridge long, thin, smooth. Epistome with anterior margin formed by thin concave edges joining medially.Buccal cavity relatively short, almost as broad as long and squarish, not delineated laterally. Mxp3 rather short, leaving distinct rhomboidal median gap when closed; ischium and merus with slight short sulcus, without setose ridge; palp inserted near middle of anterior margin of merus; palp short, with three mobile articles visible externally, all included in the buccal cavity; exopod exposed, slender, with vestigial flagellum. Pterygostomial area very setose, subhepatic area not setose. Pereiopods with tufts of setae in youngs and adults, glabrous in larger individuals. Chelipeds subequal in adult males, chela strongly inflated; fingers slightly shorter than smooth palm, both gaping; dactylus with small proximal tooth; fixed finger with distal tooth. Ambulatory legs relatively slender, second and third legs longest. Sterno-pleonal cavity very deep; its extremity not far from suture 2/3; ridge on sternite 4 faint, surrounding telson only. Male pleon with all somites free, long, edged with thin setae; somite 6 with straight margins; telson long, acutely triangular. Thoracic sternum: sternite 1 spine-like at lower level than sternite 2, with scattered short pubescence not obscuring surface; other sternites glabrous; sternite 2 narrower, with straight margins; sternites 3 and 4 fused, with slightly concave lateral margins; sternite 7 without sulcus. Median line along sternites 8 and 7. Locking structure as largely developed and salient rugose prominence, quite close to suture 4/5 and pleonal socket with calcified border, therefore an apparently functional apparatus. Male gonopore sternal, not very distant from P5. Soft and long setae on P3 and P4 coxae, forming a large setal pouch between P3/P4. G1 relatively elongate, slender; distal part almost straight to distinctly bent inwards (towards median line of thoracic sternum) and with numerous long setae; pectinated part spatuliform, subtruncate. G2 very small, bent. Vulva big, rounded, close to suture 5/6, with salient cover and operculum.