Massinium, a new genus in the family Phyllophoridae (Echinodermata : Holothuroidea : Dendrochirotida) with description of a new south-west Indian Ocean species M-maculosum

Several specimens of a phyllophorid holothuroid collected from off the KwaZulu-Natal coast, Republic of South Africa, represent a species new to science. In the structure of the calcareous ring and the absence of tables from the body wall it resembles Neothyonidium magnum and N. arthroprocessum. In all three species the posterior processes of the calcareous ring are distally joined. Hence, they do not correspond to the diagnosis of Neothyonidium as defined by its type species, N. hawaiense, and are now assembled in the new genus Massinium. The new species is described as Massinium maculosum. The three species are keyed and a distribution map is provided.