Morphostructural data and phylogenetic relationships of a new cnidarian myxosporean infecting spleen of an economic and ecological important bryconid fish from Brazil

Author(s)

Milanin, Tiago ^[1] ; Mathews, Patrick D. ^{[2, 3]} ; Morandini, Andre C. ^{[2, 4]} ; Mertins, Omar ^[5] ; Audebert, Fabienne ^[3] ; Pereira, Jose O. L. ^[1] ; Maia, Antonio A. M. ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Anim Sci & Food Technol, Dept Basic Sci, BR-13635900 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Biosci, Dept Zool, BR-05508090 Sao Paulo - Brazil

^[3] Sorbonne Univ, CNRS, IRD, UCA, Lab Biol Organismes & Ecosyst Aquat, Museum Na, CP 26, F-75005 Paris - France

^[4] Univ Sao Paulo, Ctr Biol Marinha, BR-11612109 Sao Sebastiao - Brazil

^[5] Univ Fed Sao Paulo, Dept Biophys, Paulista Med Scholl, BR-04023062 Sao Paulo - Brazil

• Document type: Journal article
• Source: Microbial Pathogenesis; v. 150, JAN 2021.
• Web of Science Citations: 0

Abstract

A new cnidarian myxosporean infecting the spleen of an economic and ecological important bryconid fish (Salminus franciscanus) is described based on integrative taxonomic approach including morphological, ultrastructural, biological traits, geography, molecular data and phylogenetic analysis. In a total of thirty specimens examined, nineteen (63.3%) were infected by an undescribed parasite species belonging to the genus Myxobolus. Plasmodial development was asynchronous, with young development in the periphery and mature myxospores in the central area and without projections and microvilli in the plasmodial wall. Mature myxospores were ovoid in shape and measured 7.9 +/- 0.2 mu m (7.6-8.1 mu m) in length and 5.4 +/- 0.1 mu m (5.0-5.6 mu m) in width. The two polar capsules were equal in size, occupying a little more than half of the myxospore body, measuring 4.0 +/- 0.2 um (3.9-4.1 mu m) in length and 1.7 +/- 0.1 mu m (1.5-1.8 mu m) in width. The polar tubules coiled in six turns, perpendicular to the long axis of polar capsule. Phylogenetic analysis placed the new species within a Glade containing nine myxobolid species from South American characiforms fish and appears as a close species of Myxobolus pantanalis. Nevertheless, the sequences of the new species and M. pantanalis have a large genetic divergence of 13.5% in their SSU rDNA. In light of the differences observed from the integrative taxonomy, we confidently considered that this isolate is a new species of cnidarian myxosporean, M. douradae n. sp., increasing the knowledge of diversity of this enigmatic group of cnidarians. (AU)

• FAPESP's process: 15/21007-9 - Recognizing the diversity of jellyfishes (Medusozoa, Rhopaliophora)
• Grantee: André Carrara Morandini
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/13147-6 - Studies of the differential expressed immune genes in organs of ornamental fish in response to myxosporeans infection
• Grantee: Patrick Mathews Delgado
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• 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: 15/18807-3 - 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