Holothuria (Selenkothuria)

Deichmann, 1958

10 species

Soft skinned forms with numerous cylindrical feet, forming a more or less distinct ventral sole, sometimes arranged in three broad bands; dorsally numerous minute papillae, not conspicuous, rarely forming low warts. Tentacles more or less terminal in position, often bushy, adapted for plankton catching (?). Certain species with numerous stone canals, others with single large one; usually one polian vesicle; gonads as divided threads in a tuft behind the low calcareous ring. Cuvierian tubules present. An external layer of tables usually completely lacking, though vestiges of some tables found in young individuals or certain species. The inner layer consisting of small rods or plates, smooth or spinous. Ventral feet with large end plate and walls supported by rods or plates of the same size as those in the skin, rarely supporting rods present, Dorsal appendages with reduced end plate or none, and often more curved shorter rods. (Deichmann, 1958)

Tentacles 20; pedicels crowded but more or less distinctly arranged in three rows on the ventral sole, papillae small, numerous, scattered dorsally; body wall soft, not very thick, 1(1-3) mm; body flattened with ventral sole and arched dorsally; size moderate up to 150 (rarely 200) mm; calcareous ring with radial plates up to three times as long as the interradials, the latter usually with the outer surface slightly concave; spicules consisting of perforated or rugose plates or rods, tables rare to more often totally absent, when present (2 species) always in rudimentary form and sparsely distributed in the body wall. (Rowe 1969)