Thyonina

Thandar, 1990

1 species

Small cylindrical species up to 55 mm long. Pedicels numerous, scattered. Tentacles 10, ventral two reduced. Calcareous ring short tubular, radials with long paired projections, both ring and prolongations broken into a few larger pieces. Body wall spicules minute, slender, straight or slightly curved, smooth rods, expanded and often digitated at ends which have a single large and one or more smaller holes. Pedicels with an end plate (up to 0.135 mm in diameter) with numerous small central holes and a single series of large marginal holes, both types sharply demarcated. Introvert with rosettes. Tentacles with simple plates and rods, often provided with spiny margins. (Thandar, 1990)