Genus Placatenella n. gen.

Diagnosis. As for the family, but with interambulacrum 5 continuous, basicoronal 5 contiguous with both postbasicoronals; postbasicoronals in interambulacrum 5 greatly elongated and arrow-shaped, at least three times the length of more distal oral postbasicoronals in the same interambulacrum; periproct marginal inside posterior notch.

Type species. Abertella complanata Brito, 1981 .