Redescription of Pseudacanthocanthopsis secunda (Yamaguti and Yamasu, 1960) (Copepoda: Chondracanthidae) parasitic on marine fishes from the Seto Inland Sea, Japan and the East China Sea off Japan and Korea

Abstract

A redescription of the chondracanthid copepod Pseudacanthocanthopsis secunda (Yamaguti and Yamasu, 1960) is provided based on adult females collected from the Indian perch, Apogon lineatus Temminck and Schlegel, 1842, captured in the Seto Inland Sea, Japan, and the East China Sea off Japan and Korea, along with additional material from the fine-patterned puffer Takifugu poecilonotus (Temminck and Schlegel, 1850) and red seabream Pagrus major (Temminck and Schlegel, 1843) captured in the Seto Inland Sea. The male of P.secunda is also described for the first time. Our results revealed that P.secunda is a valid member of Pseudacanthocanthopsis, and it can be distinguished from the other three congeners by having one ventrolateral and two anterior pairs of rounded head processes, a reniform trunk, a double row of teeth along the concave margin of the mandible and a lateral swelling on the leg 1 protopod in the female.