FIRST DETECTION OF ENTEROMYXUM LEEI FROM CREOLE WRASSE BODIANUS PARRAE (BLOCH & SCHNEIDER, 1801) WITH EXPANDED MORPHOLOGICAL AND MOLECULAR CHARACTERIZATION OF THE PARASITE.

Abstract

In June of 2022, 3 creole wrasses, Bodianus parrae, from a public display aquarium were submitted for diagnostic examination at Mississippi State University's College of Veterinary Medicine. Fresh myxospores recovered from the intestines were morphologically consistent with previous accounts of Enteromyxum leei (Diamant, Lom & Dyková, 1994). Molecularly, myxospores from the present study were 99.7-100% and 99.7-99.8% similar to publicly available E. leei sequences at 18S small subunit ribosomal (18S) and 28S large subunit ribosomal (28S) genes, respectively. Internal transcribed spacer region 1 (ITS1), 5.8S ribosomal rRNA gene (5.8S), and internal transcribed spacer region 2 (ITS2) sequences were 95.8-98.0%, 100%, and 99.9% similar, respectively, to the only publicly available data from these regions from E. leei. Eukaryotic elongation factor 2 (EEF2) sequences were 98.8% similar to the available EEF2 sequence of E. leei in GenBank. Lastly, cytochrome c oxidase subunit 1 (COI) sequences were 98.6% similar to previously published data. Bayesian phylogenetic analyses using both single locus 18S sequence data, concatenated 18S, 28S, and EEF2 data, and concatenated 18S, 28S, and COI amino acid sequences from each of the 3 wrasses grouped E. leei from the present study with previously published E. leei sequences with high Bayesian and maximum likelihood support. This is the first account of E. leei from B. parrae. Histological assessment reveals pathological changes to intestinal epithelia consistent with previous accounts of E. leei, with 18S, ITS1, 5.8S, ITS2, 28S, EEF2, and COI sequence data providing greater phylogenetic resolution of this enigmatic species. These morphological and molecular data from an enteromyxosis outbreak in a mixed-species exhibit at a public aquarium offer robust species-level identification of the causative agent, E. leei.