title: Morphological, ultrastructural and phylogenetic analyses of Myxobolus hilarii n. sp. (Myxozoa, Myxosporea), a renal parasite of farmed Brycon hilarii in Brazil.
abstract: Myxobolus hilarii n. sp. was described, based on morphology, histology, ultrastructure and 18S rDNA sequencing, infecting the kidney of Brycon hilarii (Valenciennes 1850) (Characiformes: Bryconidae) taken from fish farms in the state of São Paulo, Brazil. Thirteen specimens of B. hilarii were examined and 100% had round, white plasmodia in the kidney. The mature myxospores were rounded, measuring 11.5 ± 0.8 (9.8-13.4) μm in length, 11.0 ± 0.7 (9.7-12.4) μm in width and 7.6 ± 1.0 (6.7-9.0) μm in thickness. Polar capsules were elongated and of equal size, with 6.5 ± 0.4 (6.0-7.2) μm in length and 4.0 ± 0.2 (3.6-5.3) μm in width and their polar filaments had 5 to 7 coils. Histological analysis revealed plasmodial development in the renal tubules, causing compression and deformation of adjacent tissues and destruction of renal tubule cells. Ultrastructural analysis showed direct contact between the plasmodial wall and the host tissue and asynchronous plasmodial development. The phylogenetic analysis of South American myxobolids, based on 18S rDNA sequencing, showed the myxosporeans grouping into two main clades. M. hilarii n. sp. appears as sister species of Myxobolus piraputangae.
authors.affiliation: Departamento de Medicina Veterinária, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo (USP), Rua Duque de Caxias Norte, 225, CEP, Pirassununga, SP 13635-900, Brazil. Electronic address: kacapo@usp.br.
authors.forename: Kassia R H
authors.initials: KR
authors.lastname: Capodifoglio
authors.affiliation: Departamento de Ciências Biológicas, Universidade Federal de São Paulo (UNIFESP), Rua Professor Artur Riedel, 275, Jardim Eldorado, CEP, Diadema, SP 09972-270, Brazil; Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Caixa Postal 6109, CEP, Campinas, SP 13083-970, Brazil.
authors.forename: Edson A
authors.initials: EA
authors.lastname: Adriano
authors.affiliation: Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Caixa Postal 6109, CEP, Campinas, SP 13083-970, Brazil.
authors.forename: Tiago
authors.initials: T
authors.lastname: Milanin
authors.affiliation: Departamento de Medicina Veterinária, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo (USP), Rua Duque de Caxias Norte, 225, CEP, Pirassununga, SP 13635-900, Brazil.
authors.forename: Marcia R M
authors.initials: MR
authors.lastname: Silva
authors.affiliation: Departamento de Medicina Veterinária, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo (USP), Rua Duque de Caxias Norte, 225, CEP, Pirassununga, SP 13635-900, Brazil.
authors.forename: Antônio A M
authors.initials: AA
authors.lastname: Maia
mesh_terms: D000818:Animals; D001938:Brazil / Q000453:epidemiology; D060125:Characiformes / Q000469:parasitology*; D005393:Fish Diseases / Q000453:epidemiology / Q000469:parasitology*; D005618:Fresh Water; D007668:Kidney / Q000469:parasitology; D055766:Myxobolus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000648:ultrastructure; D010273:Parasitic Diseases, Animal / Q000453:epidemiology / Q000469:parasitology*; D010802:Phylogeny; D012337:RNA, Ribosomal, 18S / Q000235:genetics
chemical_list: D012337:RNA, Ribosomal, 18S
keywords: 18S rDNA; Brycon; Fish farm; Myxozoa; Parasite