Neothyonidium

Deichmann, 1938

10 species

Dendrochirote holothurians with 20 tentacles (10+10), which are alternately paired. The calcareous members of the ring are combined. The radialia have long forked tails which, in the middle sections, are grown together with the large, and also combined, interradialia. The calcareous bodies are towers with two-columned attachments. (Heding & Panning, 1954)

Tentacles 20, arranged in a single ring. Deposits exclusively two pillared with a few perforations. (Pawson, 1970)

Dendrochirotid holothurians with 20 tentacles in two circles of 10+10. Calcareous ring tubular, with long deeply divided posterior prolongations to radial and/or interradial plates. Body wall spicules two-pillared tables or their derivatives; short thick rods present in the southern African species. (Thandar, 1990)