Hydromedusae observed during night dives in the Gulf Stream Author Schuchert, Peter Muséum d’histoire naturelle, C. P. 6434, CH- 1211 Genève 6, Switzerland peter.schuchert@ville-ge.ch Author Collins, Richard 880 NE 33 rd Street, Boca Raton, Florida, USA rc6684@icloud.com text Revue suisse de Zoologie 2021 2021-10-21 128 2 237 356 journal article 3356 10.35929/RSZ.0049 172fa5c5-c0c4-4bd7-b710-d608237b8458 0035-418 5639938 8382D1CA-7C0E-4B1C-9591-4CEAA2F296FB 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).