Meiobenthic Polychaete Dinophilus sp. cf. gyrociliatus (Annelida: Dinophilidae) from Japan with SEM Observation and DNA Barcodes

Abstract

Tiny annelids identified as the marine meiobenthic polychaete Dinophilus gyrociliatus (Schmidt, 1857) have been reported not only from shallow water sediments but also artificial environments such as experimental aquaria almost all around the world; the species has thus been regarded to show a cosmopolitan distribution. However, various types of ciliary-band arrangements and genetic sequences have been reported from different populations, leading to a doubt on the species’ taxonomic identity. In this study, we present results of our SEM observation of Dinophilus sp. cf. gyrociliatus from Japan and provide mitochondrial 16S ribosomal RNA and cytochrome c oxidase subunit I gene sequences of Japanese populations as DNA barcodes for contributing to resolving the taxonomic uncertainty of “D. gyrociliatus”.