Redescription of a rarely encountered species Travisa chinensis Grube, 1869 (Annelida, Travisiidae), including a description of a new species of Travisa from Amoy, China

Abstract

The original description of Travisia chinensis Grube, 1869 was incomplete, leading to confusion with other species. To clarify the status of this species, we provide a redescription of, and remarks on, T. chinensis based on an examination of the type specimen. We also describe Travisia amoyanus sp. nov., collected from Xiamen (Amoy), China, and originally identified as T. chinensis by Monro (1934). The new species can be distinguished from its congeners by a combination of the following characters: the total number of segments (34 or 35) and chaetigers (33 or 34), parapodial lappets first from chaetiger 15, and a pygidium with a large ventral triangular cirrus and about six encircling lateral cirri. Genetic distances and phylogenetic analyses based on the mitochondrial (16S rRNA) and nuclear (18S rRNA) genes support the identity of the new species.