title: A microsporidian parasite of the genus Spraguea in the nervous tissues of the Japanese anglerfish Lophius litulon.
abstract: In the present study, a high percentage of Japanese anglerfish, Lophius litulon (Jordan, 1902), contained a microsporidian infection of the nervous tissues. Xenomas were removed and prepared for standard wax histology and transmission electron microscopy (TEM). DNA extractions were performed on parasite spores and used in PCR and sequencing reactions. Fresh spores measured 3.4 x 1.8 microm and were uniform in size with no dimorphism observed. TEM confirmed that only a single developmental cycle and a single spore form were present. Small subunit (SSU) rDNA sequences were >99.5% similar to those of Spraguea lophii (Doflein, 1898) and Glugea americanus (Takvorian et Cali, 1986) from the European and American Lophius spp. respectively. The microsporidian from the nervous tissue of L. litulon undoubtedly belongs in the genus Spraguea Sprague et Vivra, 1976 and the authors suggest a revision to the generic description of Spraguea to include monomorphic forms and the transfer of Glugea americanus to Spraguea americana comb. n. Since no major differences in ultrastructure or SSU rDNA sequence data exist between Spraguea americana and the microsporidian from the Japanese anglerfish, they evidently belong to the same species. This report of Spraguea americana is the first report of a Spraguea species from L. litulon and indeed from the Pacific water mass.
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo, Tokyo 113-8657, Japan. amaf100@mail.ecc.tokyo-u.ac.jp
authors.forename: Mark A
authors.initials: MA
authors.lastname: Freeman
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yokoyama
authors.forename: Kazuo
authors.initials: K
authors.lastname: Ogawa
mesh_terms: D000818:Animals; D001483:Base Sequence; D016000:Cluster Analysis; D017931:DNA Primers; D004275:DNA, Ribosomal / Q000235:genetics; D005393:Fish Diseases / Q000469:parasitology*; D005399:Fishes; D006652:Histological Techniques / Q000662:veterinary; D007564:Japan; D008854:Microscopy, Electron / Q000662:veterinary; D016814:Microsporidia / Q000235:genetics* / Q000648:ultrastructure*; D008969:Molecular Sequence Data; D009474:Neurons / Q000469:parasitology; D010802:Phylogeny; D011529:Protozoan Infections, Animal; D017422:Sequence Analysis, DNA / Q000662:veterinary; D013045:Species Specificity; D033761:Spores, Protozoan / Q000166:cytology
chemical_list: D017931:DNA Primers; D004275:DNA, Ribosomal