title: Morphology and 18S rDNA gene sequence of Blepharisma sinuosum Sawaya, 1940 (Ciliophora: Heterotrichea) from Brazil.
abstract: The morphology and morphometric data of seven populations of Blepharisma sinuosum from southeastern Brazil were investigated. The description is based on live observations, protargol impregnation, and scanning electron microscopy. Blepharisma sinuosum measures 75-255μm in length and 25-93μm in width and has a spindle-shaped body, pink color, a single contractile vacuole located at the posterior end, 50 adoral membranelles, a conspicuous paroral, 17-35 somatic kineties, a moniliform macronucleus with 2-7 connected nodules, and 3-20 micronuclei. Morphological comparisons with similar species were performed and suggest that B. americanum is the junior synonym of B. sinuosum. The 18S rDNA gene sequence of B. sinuosum was obtained and compared with that of other Blepharisma species. The length and GC content of the obtained sequence is 1652bp and 47.03%, respectively, and has a very high structural similarity (99.9%) with the B. undulans sequence. The validity of the classification of Blepharisma species in morphonuclear subgenera is also discussed.
authors.affiliation: Laboratório de Protistologia, Departamento de Zoologia, Universidade Federal do Rio de Janeiro, Brazil. Electronic address: noemi.fernandes@yahoo.com.br.
authors.forename: Noemi Mendes
authors.initials: NM
authors.lastname: Fernandes
authors.forename: Roberto Júnio Pedroso
authors.initials: RJ
authors.lastname: Dias
authors.forename: Marcus Vinicius Xavier
authors.initials: MV
authors.lastname: Senra
authors.forename: Carlos Augusto Gomes
authors.initials: CA
authors.lastname: Soares
authors.forename: Inácio Domingos
authors.initials: ID
authors.lastname: da Silva Neto
mesh_terms: D000704:Analysis of Variance; D001483:Base Sequence; D001938:Brazil; D016798:Ciliophora / Q000145:classification / Q000166:cytology* / Q000235:genetics* / Q000648:ultrastructure; D014644:Genetic Variation; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D010802:Phylogeny; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D016415:Sequence Alignment
chemical_list: D012337:RNA, Ribosomal, 18S
keywords: 18S rDNA; Blepharisma; Brazil; Ciliophora; Macronucleus; Morphology