Apentamera

Deichmann, 1941

1 species

Small forms, a few cm long, with tube feet in 5 bands, papilliform towards the ends where 5 valves are formed; a few smaller papilliform tube feet are scattered in the dorsal interambulacra, may be lacking in small individuals. Tentacles 10, the two ventral smaller. Skin rigid, packed with spicules. Calcareous ring with long posterior prolongations, other internal features almost as in Pentamera. Spicules an external layer of flattened baskets almost rosette-like and easily overlooked and may possibly be lost in older individuals, and in an inner layer of regular 4 holes knobbed buttons. Feet with end plate smaller in the terminal appendages; walls packed with curved supporting tables with 2 pillars and a few blunt teeth. Introvert with oblong tables or plates with slightly knobbed edge. Tentacles packed with plates and rods which gradually decrease in size in the branches, apparently no rosettes. (Deichmann, 1941)

There are feet only in the radii, toward the body ends papillae shaped; single papillae in the dorsal interradii. There are ten tentacles, the two ventral ones smaller. The calcareous ring has long forked tails. In the surface of the body wall, there are flat rosette type cups. Under those there are plates with 4 perforations and bumps. The feet have terminal end plate and 2 columned tables. In the introvert there are elongated tables or plates whose edge has weak bumps. The tentacles have plates and rods. (Panning, 1949)