Aphelodactyla

Clark, 1907

4 species

Tentacles 15, simple and without digits, but with ampullae. Body more or less tapering posteriorly but there is no distinctly set off caudal appendage. Calcareous ring very broad, the radial pieces with evident, but short, posterior prolongations. Calcareous deposits often wanting (usually present at extreme posterior end), and when present relatively insignificant, in the form of small oval or dumb-bell shaped bodies or perforated plates. Phosphatic deposits wanting. (Clark, 1907)

Tentacles 15 without digits. Ampullae present. Body gradually tapering into the short caudal appendage. Radials with short but marked posterior projections. Calcareous deposits irregular bodies and small perforated plates. They are usually absent in the body wall, but then often found close to the caudal appendage. No real retractors present. (Heding, 1931)