Nomenclatural status of Pyuridae and Bolteniidae (Tunicata, Ascidiacea) with comments on several included genera

Detailed discussion of the nomenclatural history of the Pyuridae, Bolteniidae and related families is provided. It is shown that the valid nomen for the family currently known as Pyuridae is Bolteniidae. The generic nomen "Claudenus Kott, 1998" is not available and Claudenus is re-established here as intentionally new nomen (Claudenus Sanamyan & Sanamyan gen. nov.) The generic nomen Cratostigma is not available but no replacement nomen is suggested because we suppose that this genus may be congeneric with Bolteniopsis. The generic nomen Eupera Michaelsen, 1904 is invalid being a junior homonym, but a new replacement nomen is not suggested because it is synonymized here with Culeolus.