Ultrastructure and phylogeny of the parasite Henneguya carolina sp. nov. (Myxozoa), from the marine fish Trachinotus carolinus in Brazil

Abstract

Microscopic and molecular procedures are used to describe a new myxosporean species, Henneguya carolina sp. nov., found infecting the intestine of the marine teleost fish Trachinotus carolinus on the southern Atlantic coast of Brazil. Spherical to ellipsoid cysts, measuring up to ~750 µm, display synchronous development. Mature myxospores are ellipsoidal with a bifurcated caudal process. Myxospore body length, width, and thickness are 12.7 ± 0.8 (12.0-13.4) µm, 8.8 ± 0.6 (7.5-9.6) µm, and 5.8 ± 0.4 (5.0-6.4) µm, respectively; 2 equal caudal processes are 16.8 ± 1.1 (15.9-18.0) µm long, and the total myxospore length is 29.4 ± 0.8 (28.4-30.4) µm. Two pyriform polar capsules measure 5.0 ± 0.5 (4.6-5.6) × 2.4 ± 0.4 (1.9-2.9) µm, and each contains a polar filament forming 3 to 4 coils. Sporoplasm is binucleated and presents a spherical vacuole surrounded by numerous globular sporoplasmosomes. Molecular analysis of the small subunit rRNA gene by maximum parsimony, neighbor joining, and maximum likelihood reveals the parasite clustering together with other myxobolids that are histozoic in marine fish of the order Perciformes, thereby strengthening the contention that the host phylogenetic relationships and aquatic environment are the strongest evolutionary signal for myxosporeans of the family Myxobolidae.

Description of Henneguya jaczoi sp. n. (myxosporea, myxobolidae) from Perca fluviatilis (L.) (pisces, percidae) with some remarks on the systematics of Henneguya spp. of european fishes

“…Henneguya is the second most species-rich genus of myxosporeans after Myxobolus, with over 195 species (Eiras, 2002;Eiras and Adriano, 2012). Most species described recently from different fishes have proper morphological descriptions supported by histological and molecular data (Székely et al, 2009;Ye et al, 2012;Yokoyama et al, 2012;Carriero et al, 2013;Rocha et al, 2014). Some other species described more than a hundred years ago, however, have only scanty data on morphology, insufficiently designated habitats and more than one host in their original description.…”

Morphological and molecular characterization of myxobolids (Cnidaria, Myxozoa) infecting cypriniforms (Actinopterygii, Teleostei) endemic to the Iberian Peninsula

“…Thus, morphology-based comparisons remain necessary to differente between the many species that are without molecular data. Acknowledging that phylogenetic studies widely show the vertebrate host group as the most relevant evolutionary signal for myxobolids (see [7,21,62]), the morphological comparisons performed in this study only took into consideration congeners reported from closely related cypriniform species.…”

“…Genomic DNA extraction was performed using a GenElute™ Mammalian Genomic DNA Miniprep Kit (Sigma-Aldrich, St Louis, USA), following the manufacturer's instructions. The SSU rDNA gene was amplified using both universal and myxosporean-specific primers: the 5 0 -end by pairing the primer 18E (5 0 -CTG GTT GAT CCT GCC AGT-3 0 ) [29] with the primers MyxospecR (5 0 -CAA CAA GTT GAT AGG GCA GAA-3 0 ) [22], ACT3r (5 0 -ATT GTT CGT TCC ATG-3 0 ) [62] and MYX4R (5 0 -CTG ACA GAT CAC TCC ACG AAC-3 0 ) [26]; and the 3 0 -end by pairing the primers MyxospecF (5 0 -TTC TGC CCT ATC AAC TTG TTG-3 0 ) [22], ACT3f (5 0 -CAT GGA ACG AAC AAT-3 0 ) [26] and MYX4F (5 0 -GTT CGT GGA GTG ATC TGT CAG-3 0 ) [63] with the primer 18R (5 0 -CTA CGG AAA CCT TGT TAC G-3 0 ) [77]. PCRs were performed in 50 lL reactions using 10 pMol of each primer, 10 nMol of each dNTP, 2.0 mM MgCl 2 , 5 lL 10 Â Taq polymerase buffer, 2.5 units Taq DNA polymerase (NZYTech, Lisbon, Portugal), and approximately 50-100 ng of genomic DNA.…”

Henneguya ovata n. sp. (Myxosporea: Bivalvulida), causing severe enteric henneguyosis of net-cage-cultured ovate pompano, Trachinotus ovatus in China

“…Moreover, the infection site (gill lamellae vs. intestinal wall) and host affinity (Latidae vs. Carangidae) which has intensively been approved to provide strong evolutionary for myxobolid species clustering (Yokoyama et al, 2005;Fiala, 2006;Rocha et al, 2014), can remarkably delimit these two marine Henneguya species. Among less than 40 Henneguya species recording from marine fish hosts, only 9 species were found from the gastrointestinal tract (Eiras, 2002;Eiras and Adriano, 2012;Rocha et al, 2014). Strict morphological comparisons showed that the spore body length, caudal appendage length and total length of H. ovata n. sp.…”