The first definitive record of the giant larvacean, Bathochordaeus charon, since its original description in 1900 and a range extension to the northeast Pacific Ocean

摘要

Background Larvaceans in the genus Bathochordaeus are large, often abundant filter feeders found throughout much of the world ocean. The first described species, Bathochordaeus charon , was reported over 100?years ago by Chun. However in the time since, few specimens have matched Chun’s original description, resulting in ambiguity on the validity of B. charon as a species. Methods Specimens of Bathochordaeus charon were identified based on morphological traits, molecular data and observations made on high definition video. Results The first records of Bathochordaeus charon from the northeast Pacific Ocean off central California and Oregon, USA are reported. Morphology and molecular data clearly distinguish B. charon from its congener, B. stygius . Conclusions This paper establishes the first review of Bathochordaeus charon since its original description, extends the range of this species to the northeast Pacific Ocean, and provides the first molecular evidence for two species of Bathochordaeus .