Gymnonereidinae new subfamily: the Nereididae (Polychaeta) with bifid parapodial neurocirri

Summary

Among the Nereididae without (hardened chitinous?) paragnaths, the genera with bifid parapodial neurocirri have in common also a pronounced inequality between the anterior and medio-posterior body regions in the number of setae per parapodium; this leads to a peculiar habitus of most of these forms. A new subfamily, Gymnoneredinae, is proposed for the previously recognized genera Ceratocephale Malmgren, Gymnonereis Horst, and Tambalagamia Pillai; Micronereides Day has also been included. Two new species, Ceratocephale hartmanae and C. oculata, are described, and additions to the descriptions of eight of the previously known nine other members of the family made, primarily based on a study of type material. New species combinations are proposed, and generic diagnoses amended.