title: Morphological and molecular characterization of Pseudocohnilembus longisetus Thompson, 1965 from farmed black rockfish Sebastes schlegelii in Korea.
abstract: The morphology, infraciliature, silverline system, and the small subunit ribosomal RNA (SSU rRNA) of the little-known marine scuticociliate Pseudocohnilembus longisetusThompson, 1965 from the diseased black rockfish Sebastes schlegelii in Korea were studied. This scuticociliate possessed the typical characteristics of the genus Pseudocohnilembus, but could be discriminated from Pseudocohnilembus hargisi, and Pseudocohnilembus persalinus in terms of the body size, shape, the number of somatic kineties and kinetids in somatic kinety 1, and the number/position of contractile vacuole pores. The SSU rRNA gene of P. longisetus was sequenced in order to gain a better understanding of appropriate phylogenetic classification. The SSU rRNA was 1754 bp and the sequence was deposited in GenBank under accession number FJ899594. The SSU rRNA gene sequences of P. longisetus had an identity of 98.1%, 96.8% and 95.3% with P. hargisi, P. persalinus, and Pseudocohnilembus marinus SSU rRNA sequences, respectively. Our population of P. longisetus belonged to the genus Pseudocohnilembus and was in an isolated position based on the SSU rRNA gene tree, which was consistent with the conclusions based on the morphological studies. However, further investigation is required to determine the pathogenicity of this species.
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Special Self-Governing Province, 690-756, Republic of Korea.
authors.forename: Ilson
authors.initials: I
authors.lastname: Whang
authors.forename: Hyun-Sil
authors.initials: HS
authors.lastname: Kang
authors.forename: Jehee
authors.initials: J
authors.lastname: Lee
mesh_terms: D000818:Animals; D017756:Aquaculture; D016798:Ciliophora / Q000166:cytology* / Q000235:genetics*; D016770:Ciliophora Infections / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D005393:Fish Diseases / Q000453:epidemiology / Q000469:parasitology*; D005399:Fishes; D010802:Phylogeny; D012335:RNA, Ribosomal / Q000145:classification / Q000235:genetics; D056910:Republic of Korea / Q000453:epidemiology
chemical_list: D012335:RNA, Ribosomal