Infection of Pennellids (Copepoda: Siphonostomatoida) from Marine Ranched Fishes in Korea

Abstract

Pennellids (Copepoda: Pennellidae) comprised of highly transformed, elongated copepods parasitic on marine fishes and this family has the largest of all copepods. Some of these copepods are ectoparasitic and some are deeply inserted into the body of their host. In Korea, some of the marine ranched fishes at Tongyeong marine living resources research & conservation center (TMRC), KIOST, have been found with the infection of pennellids from two different hosts such as the black scraper Thamnaconus modestus and the Korean rockfish Sebastes schlegelii. The identified pennellids are Peniuclus minuticaudae Shiino, 1956 and P. truncatus Shiino, 1956. Both were first reported in 1956 from Japan and hence this is the first report on the occurrence of these pennellids from Korea. Attachment site was soft fin rays. Ecology of P. minuticaudae for one year has been studied from TMRC. Redescription of these two pennellids are provided based on post metamorphic adult females. (1) P. minuticaudae can be distinguished from the other two closely related congeners P. ostraciontis Yamaguti, 1939 and P. truncatus by having a well developed triangular-shaped abdomen, which are rudimentary in other two species. (2) P. truncatus can be distinguished from the other two closely related congeners P. minuticaudae and P. ostraciontis by having a rudimentary abdomen, long neck and setae on leg 1 with the former; long no the body of their host. In Korea, some of the marine ranched fishes at Tongyeong marine living resources research & conservation center (TMRC), KIOST, have been found with the infection of pennellids from two different hosts such as the black scraper Thamnaconus modestus and the Korean rockfish Sebastes schlegelii. The identified pennellids are Peniuclus minuticaudae Shiino, 1956 and P. truncatus Shiino, 1956. Both were first reported in 1956 from Japan and hence this is the first report on the occurrence of these pennellids from Korea. Att