Molecular Phylogeny and taxonomy of a new Myxobolus species from the endangered ornamental fish, Otocinclus cocama endemic to Peru: A host-parasite coextinction approach

Author(s)

Mathews, Patrick D. ^{[1, 2]} ; Mertins, Omar ^[3] ; Milanin, Tiago ^[4] ; Espinoza, Luis L. ^[5] ; Flores-Gonzales, Anai P. ^[6] ; Audebert, Fabienne ^[2] ; Morandini, Andre C. ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Biosci, Dept Zool, BR-05508090 Sao Paulo - Brazil

^[2] Sorbonne Univ, Unite Biol Organismes & Ecosyst Aquat, Museum Natl Hist Nat, CNRS, IRD, UCA, CP 26, F-75005 Paris - France

^[3] Univ Fed Sao Paulo, Paulista Med Scholl, Dept Biophys, BR-04023062 Sao Paulo - Brazil

^[4] Univ Sao Paulo, Fac Anim Sci & Food Technol, Dept Basic Sci, BR-13635900 Sao Paulo - Brazil

^[5] Natl Univ San Marcos, Fac Vet Med, Lab Biol & Mol Genet, Lima 2800 - Peru

^[6] Univ Fed Amapa, Postgrad Program Trop Biodivers, BR-68903419 Macapa - Brazil

• Document type: Journal article
• Source: Acta Tropica; v. 210, OCT 2020.
• Web of Science Citations: 0

Abstract

A new Myxobolus species is described infecting gill filaments of the endangered ornamental fish Otocinclus cocama from Peruvian Amazon. In a total of 35 fish examined, five (14.3%) had myxozoan plasmodia. Taxonomic analysis was performed integrating multiple characters, including morphometrical, biological traits, ssrDNA sequence data and host ecological characters. Myxospores of M. iquitoensis n. sp. were ovoid in shape from the frontal view and measured 17.6 +/- 1.2 mu m (16.2-19.8 mu m) in length and 10.5 +/- 0.7 mu m (9.8-12 mu m) in width. The two polar capsules were elongate in shape, equal in size and occupying almost half of the myxospore body. They measured 8.7 +/- 0.4 mu m (6.9-9.3 mu m) in length and 3.3 +/- 0.2 mu m (3-3.6 mu m) in width. The polar tubules presented six to seven turns. Molecular phylogenetic analysis revealed that the obtained ssrDNA sequence did not match any existing sequences in GenBank but showed M. iquitoensis n. sp. to be a close species of M. figueirae. Nonetheless, the ssrDNA sequences of those species show large genetic divergence. This is the first description and phylogenetic study of a myxozoan parasitizing fish of the genus Otocinclus from South America, as well the first report of these parasites infecting a fish belonging to the Loricariidae family from Amazon basin. Considering the endangered status of the host, the high degree of host-specificity of freshwater histozoic myxobolids, the low occurrence shown by the new myxozoan, and the fact that this is the only host known for this myxozoan, the conservation status of the new species of myxozoan is likely to be connected to the future survival of its host. (AU)

• FAPESP's process: 16/13368-4 - Nanostructured systems: from membrane biomimetic models to carriers of bioactives
• Grantee: Karin Do Amaral Riske
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 15/18807-3 - Detection of myxosporean in oligochaetes from fish farms of hybrid pintado (Pseudoplatystoma corruscans x Pseudoplatystoma reticulatum) in Mato Grosso do Sul state, Brazil
• Grantee: Tiago Milanin
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/20482-3 - Diversity of microscopic cnidarians from the Amazon Basin with emphasis on phylogeny, systematic and interaction with their hosts
• Grantee: Patrick Mathews Delgado
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/23948-5 - Improvement of the polysaccharide chitosan properties for its application in liposomes and giant vesicles
• Grantee: Omar Mertins
• Support Opportunities: Regular Research Grants
• FAPESP's process: 15/21007-9 - Recognizing the diversity of jellyfishes (Medusozoa, Rhopaliophora)
• Grantee: André Carrara Morandini
• Support Opportunities: Regular Research Grants