Psolidae is a family of sea cucumbers, marine animals with elongated bodies, leathery skins and tentacles that are found on the sea bed. Description Members of the family Psolidae are small and inconspicuous sea cucumbers found in crevices and under boulders. They have a crown of branched tentacles, calcareous plates on the skin of the trunk and a basal sole that can move across the substrate. Some genera have papillae above but these are lacking in species of the genus Psolus. List of genera Ceto Gistel, 1848 -- 1 species Echinopsolus Gutt, 1990 -- 4 species Ekkentropelma Pawson, 1971 -- 2 species Lissothuria Verrill, 1867 -- 9 species Neopsolidium Pawson, 1964 -- 2 species Psolidium Ludwig, 1887 -- 51 species Psolus Jaeger, 1833 -- 55 species References Echinoderm families Dendrochirotida