Leptopentacta H.L. Clark, 1938

Mezali, Karim, Thandar, Ahmed S. & Khodja, Ihcene, 2020, Paraleptopentacta, a new Mediterranean and north-west Atlantic sea cucumber genus, with the first record of P. tergestina n. comb. (Echinodermata Dendrochirotida: Cucumariidae) from the north-western Algerian coast, Zootaxa 4860 (2), pp. 199-210 : 204-205

Genus Leptopentacta H.L. Clark, 1938

Cucumaria (partim) Sars, 1859: 132.

Parocnus Deichmann, 1941 (preoccupied)—replaced by Cherbocnus Thandar (in Thandar & Mjobo, 2014).

Trachythyone (partim) Panning, 1949:426.

Leptopentacta H.L. Clark, 1938: 453 ; Panning, 1966 (partim): 56.

Diagnosis. (After H.L. Clark 1938, Deichmann 1941, Panning 1966, amended herein). A genus of Cucumariidae with an elongate, slender, more or less curved body, usually pentagonal in cross-section; tube feet rigid, non-retractile, relatively few, in a straight or zigzag single or double rows, confined to ambulacra, often more or less crowded in each ventral ambulacrum. Tentacles 10, dendritic, small, with ventral pair reduced. Calcareous ring always with posteriorly forked radial plates. Body wall either encased in a firm calcified epidermis comprising scales or enlarged lenticular bodies covered with a course reticulum and often also numerous small, smooth to knobbed buttons beneath these. External layer of ossicles as rosettes only, or baskets only, or both rosettes and baskets, or absent.

Type species. Leptopentacta grisea H.L. Clark, 1938 (by original designation).

Other species included herein. L. imbricata ( Semper, 1867) (with synonyms O. typicus Théel, 1886 ; O. javanicus Sluiter,1880 ); L. bacilliformis ( Koehler & Vaney, 1908) ; L. panamica Deichmann, 1941 ; L. punctabipedia Cherbonnier, 1961 ; and hesitantly? L. nina Deichmann, 1941 .

Remarks. This genus was established only for the type species by H.L. Clark (1938). Since then various other species were included in it or described as new, raising the figure to 11. The fate of some of these species is considered above and some are now transferred to the new genus Paraleptopentacta . Hence, only six species now remain in the genus, which appears to be clearly tropical Indo-Pacific in distribution.