title: Ultrastructure and phylogeny of Glugea arabica n. sp. (Microsporidia), infecting the marine fish Epinephelus polyphekadion from the Red Sea.
abstract: A new microsporidian species, Glugea arabica n. sp., is reported infecting the intestinal wall of the marine teleost Epinephelus polyphekadion (=microdon) collected from the Red Sea coast off Saudi Arabia, and described on the basis of microscopic and molecular procedures. Spherical blackish xenomas formed parasitophorous vacuoles completely packed with several parasitic developmental stages, including spores. The nuclei were monokaryotic in all developmental stages. Spores were ellipsoidal to pyriform and measured 6.3 ± 0.3 (5.9-6.6) μm in length and 3.3 ± 0.4 (2.9-3.7) μm in width. A lamellar polaroplast surrounded the uncoiled portion of the polar filament, which extended into the spore's posterior pole and formed 27-29 coils organized in three or four rows. The posterior vacuole, located at the spore's posterior pole, appeared surrounded by the polar filament coils and displayed an irregular matrix composed of light material, in which was located the posterosome. Molecular analysis of the rRNA genes, including the ITS region, was performed using maximum parsimony, neighbor-joining and maximum likelihood methodologies. The ultrastructural features observed, in combination with the molecular data analysed, suggests the parasite to be a new species of the genus Glugea.
authors.affiliation: Laboratory of Cell Biology, Institute of Biomedical Sciences (ICBAS/UP), University of Porto, 4050-313 Porto, Portugal; Laboratory of Animal Pathology, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/UP), University of Porto, 4099 Porto, Portugal; Zoology Department, College of Sciences, King Saud University, 11451 Riyadh, Saudi Arabia. Electronic address: azevedoc@icbas.up.pt.
authors.forename: Carlos
authors.initials: C
authors.lastname: Azevedo
authors.affiliation: Zoology Department, College of Sciences, King Saud University, 11451 Riyadh, Saudi Arabia; Zoology Department, Faculty of Science, Beni-Suef University, Egypt.
authors.forename: Abdel-Azeem S
authors.initials: AA
authors.lastname: Abdel-Baki
authors.affiliation: Laboratory of Cell Biology, Institute of Biomedical Sciences (ICBAS/UP), University of Porto, 4050-313 Porto, Portugal; Laboratory of Animal Pathology, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/UP), University of Porto, 4099 Porto, Portugal.
authors.forename: Sónia
authors.initials: S
authors.lastname: Rocha
authors.affiliation: Zoology Department, College of Sciences, King Saud University, 11451 Riyadh, Saudi Arabia.
authors.forename: Saleh
authors.initials: S
authors.lastname: Al-Quraishy
authors.affiliation: Laboratory of Animal Pathology, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/UP), University of Porto, 4099 Porto, Portugal; Department of Sciences, University Institute of Health Sciences, CESPU, 4580 Gandra, Portugal.
authors.forename: Graça
authors.initials: G
authors.lastname: Casal
mesh_terms: D000818:Animals; D001492:Bass / Q000469:parasitology*; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D050220:Glugea / Q000145:classification* / Q000235:genetics / Q000648:ultrastructure*; D019156:Indian Ocean; D046529:Microscopy, Electron, Transmission; D010802:Phylogeny; D012313:RNA / Q000235:genetics; D013045:Species Specificity
chemical_list: D021903:DNA, Ribosomal Spacer; D012313:RNA
keywords: Fish parasite; Glugea arabica n. sp.; Microsporidians; Phylogeny; Red Sea; Ultrastructure