Hermadionella Uschakov 1982

Hermadionella Uschakov, 1982

Uschakov (1982) established the genus Hermadionella for Harmothoe (Eunoa) truncata Moore, 1902 (moved to Hermadion by Moore in 1908) and for Hermadion nipponicus Imajima and Hartman, 1964. We reexamined the holotype of Harmothoe (Eunoa) truncata (ANSP 268), type species of the genus, and confirm the following differentiating characters: 1) in Hermadionella the body is longer with 60 or more segments (versus up to 50 for Hermadion); 2) the notochaetae have two kinds of tips, i.e. blunt and truncate, frayed (versus all with blunt tip in Hermadion); 3) the neurochaetae have a bi- or unidentate tip (versus neurochaetae all unidentate in Hermadion). Although we consider Hermadionella a valid genus, the validity of its species is rather confused. In his description of Hermadionella truncata Uschakov pointed to the fact that H. nipponicus might be a synonym of H. truncata. Unfortunately, the holotype of truncata lacks all elytra today and the respective description given by Moore is not very accurate. We could not investigate the type material of H. nipponicus, since it is also deposited in the collection of the LACM and was not available for loan. Another intriguing point is that Pettibone (1953) considered Eunoe spinicirris Annenkova, 1937 and Eunoe subtruncata Annenkova, 1937 as junior synonyms of H. truncata, but Uschakov (1982) did not mention these species. A revision of this group is needed, but this is beyond the scope of the present paper.