Genus Protiaropsis Stechow, 1919

Heterotiara Maas, 1905: 19, invalid junior homonym of Heterotiara Pomel, 1883 (Echinodermata) .

Protiaropsis Stechow, 1919: 150, nom. nov. pro Heterotiara Maas, 1905, type species Heterotiara anonyma Maas, 1905 by original designation.

? Kanaka Uchida, 1947: 304, type species Kanaka pelagica Uchida, 1947 by monotypy.

? Gymnogonium Xu & Huang, 1994: 152, type species Gymnogonium zhengzhongii Xu & Huang, 1994 by original designation.

Diagnosis: Bythotiaridae medusae with thick umbrella, four simple radial canals; no centripetal canals; gonads interradial, no transverse folds; no secondary tentacles; no ocelli. Hydroid unknown.

Remarks: For a key to the currently known species see Du et al. (2018).