Podarkeopsis chinensis sp. nov. (Annelida, Hesionidae) is described based on specimens collected from the coast of southeast China. It is the first
Podarkeopsis species described from the Indo-Pacific, although there are already nine valid
Podarkeopsis species known from other parts of the world. This new species can be distinguished from the other
Podarkeopsis species in having a palpostyle as long as the palpophore and double aciculae in both notopodia and neuropodia, and in bearing bifid furcate chaetae which have a smooth base on the shorter tine. A phylogenetic analysis based on the concatenated sequences of five gene fragments (COI, 16S rRNA, 18S rRNA, 28S rRNA, and histone H3) from 18 specimens of
P. chinensis sp. nov. showed that they formed a monophyletic clade that is sister to
P. levifuscina. K2P genetic distances indicated that the four gene fragments (COI, 16S rRNA, 18S rRNA, and 28S rRNA) of
P. chinensis sp. nov. diverged from the corresponding sequences of the closest related species of
Podarkeopsis in GenBank and BOLD Systems by 21.1–27.5%, 20.3–23.1%, 0.1–0.2%, and 2.1–3.2%. An identification key is provided for species in the genus
Podarkeopsis.
