Hexacrista intorta (Ciliophora, Tintinnida), a new genus and species from the waters of the North European basin

In the waters of the Greenland and Barents Seas, ciliates-tintinnids have been found, their lorica combining the definitive features of several genera of the Tintinnidae family, has an unusual, unique among all Tintinnida, exterior feature, i. e. spiral folding (corrugation) of the wall. The described tintinnids in terms of shell morphology correspond to the features of the Tintinnidae family Claparède & Lachmann, 1858, sensu Bachy et al., 2012 and combine individual features of its different genera: Salpingella, Amphorellopsis, Amphorides, Steenstrupiella. Based on the set of features that are taxonomically significant in the Tintinnidae family, the studied specimens do not have any closely related forms at the genus level. The results of the research allow us to establish a new genus with a new species in its composition for Tintinnidae (Ciliophora, Tintinnida) and to present a description of a new genus of ciliates-tintinnid Hexacrista gen. nov. with the species H. intorta sp. nov. from the waters of the North European basin of the Arctic Ocean.