title: Myxidium volitans sp. nov., a parasite of the gallbladder of the fish, Dactylopterus volitans (Teleostei: Triglidae) from the Brazilian Atlantic coast--morphology and pathology.
abstract: Myxidium volitans sp. nov. (Myxozoa: Myxidiidae) parasitizing the hypertrophied green-brownish gallbladder of the teleost Dactylopterus volitans, collected in the Atlantic coast near Niterói, Brazil was described based on ultrastructural studies. The spores were fusiform, sometimes slightly crescent-shaped on average 21.7 ± 0.3 µm (mean ± standard deviation) (n = 50) long and 5.6 ± 0.4 µm (n = 30) wide. The spore wall was thin and smooth, comprising two equally-sized valves joined by a hardly visible sutural ridge. Spores containing two pyriform polar capsules (PC) (5.0 ± 0.4 × 2.3 ± 0.3 µm) (n = 30) are situated in each extremity of the spore. The PC wall was composed of hyaline layer (0.20-0.29 µm thick) and by a thin external granular layer. Each PC contains a polar filament (PF) with irregular arrangements that was projected from its apical region to the bases of PC and coiled laterally from bases to the tip of PC. Some regular striations and S-like structures in the periphery of the PFs with four-five irregular sections were observed. Based on the spore morphology, ultrastructural differences and the specificity of the host we describe this parasite as a new myxosporidian, named M. volitans sp. nov.
authors: Departamento de Biologia Celular, Instituto de Ciências Biomédicas e Laboratório de Patologia, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Porto, Portugal. azevedoc@icbas.up.pt
authors: Carlos
authors: C
authors: Azevedo
authors: Graça
authors: G
authors: Casal
authors: Sérgio Carmona
authors: SC
authors: São Clemente
authors: Leila Maria Silva
authors: LM
authors: Lopes
authors: Patrícia
authors: P
authors: Matos
authors: Abdel Azeem
authors: AA
authors: Abdel-Baki
authors: Elsa
authors: E
authors: Oliveira
authors: Edilson
authors: E
authors: Matos
mesh_terms: D000818:Animals; D001938:Brazil; D005260:Female; D005704:Gallbladder / Q000469:parasitology*; D008297:Male; D046529:Microscopy, Electron, Transmission; D055764:Myxozoa / Q000145:classification / Q000302:isolation & purification / Q000648:ultrastructure*; D010473:Perciformes / Q000469:parasitology*