Latohexapus Huang, Hsueh & Ng, 2002

Rahayu, Dwi Listyo & Ng, Peter K. L., 2014, New genera and new species of Hexapodidae (Crustacea, Brachyura) from the Indo-West Pacific and east Atlantic, Raffles Bulletin of Zoology 62, pp. 396-483 : 462-464

Latohexapus Huang, Hsueh & Ng, 2002

Latohexapus Huang, Hsueh & Ng, 2002: 652 .

Emended diagnosis. Carapace much broader than long; regions distinct, separated by deep groove, strongly granulated. Eye movable; anterolateral margin arcuate. Pterygostomial region with row of striae, granular; ischium of third maxillipeds expanded distally, longer than merus; exopod with well developed flagellum. Chelipeds asymmetrical, with prominent teeth at base of fingers. Surfaces of P2–P4 granular, dactylus upcurved. Male thoracic sternum very broad; surface prominently granular; sternites 1 and 2 fused, strongly bent backward, separated from sternite 3 by distinct transverse ridge; deep transverse groove separating thoracic sternites 3 and 4; sternoabdominal cavity extending from edge of abdominal cavity to base of chelipeds; sternite 8 exposed. Male abdomen with somites 3–5 fused; somite 6 appearing hexagonal, with median part prominently expanded into triangular projection; telson subpentagonal. G1 very slender, directed anterolaterally, distal quarter not concealed under abdomen.

Species included. Latohexapus granosus Huang, Hsueh & Ng, 2002 (type species by original designation).

Remarks. So far this is the only genus in the family that has the carapace much broader than long and with the regions distinctly demarcated. As discussed by Huang et al. (2002), the extension of the male thoracic sternal groove is comparable to the condition in Lambdophallus but several differences such as movable eyes (versus immovable eyes in Lambdophallus ), the shapes of the third maxillipeds with the ischium expanded distally in Latohexapus ( Huang et al., 2002: fig. 4D) (versus slightly convex in Lambdophallus, Manning & Holthuis, 1981 : fig. 34b), and the male abdominal somite 6 appearing hexagonal ( Huang et al., 2002: fig. 4G) (versus almost squarish in Lambdophallus, Manning & Holthuis, 1981 : fig. 34C) easily distinguishes the two genera.