title: Ultrastructural and Phylogenetic Description of Kudoa orbicularis n. sp. (Myxosporea: Multivalvulida): A Parasite Infecting the Muscle of the Fish Chaetobranchopsis orbicularis (Teleostei: Cichlidae) in the Amazon Region.
abstract: A new myxosporean species is described from the muscle of the Amazonian freshwater fish Chaetobranchopsis orbicularis (Teleostei, Cichlidae), with basis on morphometric, ultrastructural and molecular data. Numerous myxospores were observed within pseudocysts located on the hosts' dorsal and ventral muscles, near the neural spines and neural canal (spinal cord). Mature myxospores quadrangular with rounded ends in apical view, measuring 4.3 (3.6-5.0) μm in length and 5.1 (4.2-5.8) μm in width. The myxospores wall is formed by four symmetric valves. Within, four pyriform polar capsules, 2.1 (1.7-2.6) μm long and 1.3 (0.9-1.7) μm wide, located two by two in opposite sides of the myxospores longitudinal axis, each containing a polar filament forming 2-3 coils. Molecular analysis of the SSU rRNA gene by maximum likelihood, neighbor-joining and maximum parsimony confirms the parasite as a new member of the genus Kudoa, herein named Kudoa orbicularis n. sp., the second species of its genus reported from the South American freshwater fauna, and the fourth species worldwide known to occur in the freshwater environment. Furthermore, its sequence of the SSU rRNA gene constitutes the first entry of a freshwater Kudoa species in GenBank.
authors.affiliation: Laboratory of Cell Biology, Institute of Biomedical Sciences (ICBAS), University of Porto, 4050-313, Porto, Portugal.|Laboratory of Animal Pathology, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4050-123, Porto, Portugal.|Zoology Department, College of Science, King Saud University, 11451, Riyadh, Saudi Arabia.
authors.forename: Carlos
authors.initials: C
authors.lastname: Azevedo
authors.affiliation: Laboratory of Cell Biology, Institute of Biomedical Sciences (ICBAS), University of Porto, 4050-313, Porto, Portugal.|Laboratory of Animal Pathology, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4050-123, Porto, Portugal.
authors.forename: Sónia
authors.initials: S
authors.lastname: Rocha
authors.affiliation: Carlos Azevedo Research Laboratory, Federal Rural University of Amazonia, 66077, Belém, Brazil.
authors.forename: Edilson
authors.initials: E
authors.lastname: Matos
authors.affiliation: Laboratory of Cell Biology, Institute of Biomedical Sciences (ICBAS), University of Porto, 4050-313, Porto, Portugal.
authors.forename: Elsa
authors.initials: E
authors.lastname: Oliveira
authors.affiliation: Edilson Matos Research Laboratory, Federal University of Pará, 66000, Belém, Brazil.
authors.forename: Patrícia
authors.initials: P
authors.lastname: Matos
authors.affiliation: Zoology Department, College of Science, 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), University of Porto, 4050-123, Porto, Portugal.|Department of Sciences, High Institute of Health Sciences-North, CESPU, 4585-116, Gandra, Portugal.
authors.forename: Graça
authors.initials: G
authors.lastname: Casal
mesh_terms: D000818:Animals; D001938:Brazil; D023681:Cichlids / Q000033:anatomy & histology / Q000469:parasitology*; D004275:DNA, Ribosomal / Q000235:genetics; D005393:Fish Diseases / Q000469:parasitology*; D009132:Muscles / Q000469:parasitology*; D055764:Myxozoa / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000648:ultrastructure*; D010273:Parasitic Diseases, Animal / Q000469:parasitology*; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D013170:Spores / Q000648:ultrastructure
chemical_list: D004275:DNA, Ribosomal
keywords: Brazil; SSU rRNA gene; freshwater; ultrastructure