Redescription and molecular characterization of Ornithocapillaria spiculata n. comb. (Nematoda: Trichuridae) parasitizing the Neotropic cormorant Phalacrocorax brasilianus from two Argentinian lagoons

LUCAS GARBIN; MARIA DIGIANI; MARIA R. ROBLES; MARTIN M. MONTES; MARCELO KNOFF; DANIELA FUCHS; DIEGO MONTALTI; JULIA I. DIAZ

PARASITOLOGY RESEARCH

SPRINGER

Lugar: Berlin; Año: 2021

0932-0113

The subfamily Capillariinae gathers more than 300 nominal species parasitizingfive vertebrate classes distributed worldwide expanded to include 27 genera with 17 subgenera in the subfamily. Diagnostic features used for the classification into Capillariinae correspond mainly to the male caudal end. The objectives of this work wasto study the capillarids parasitizing the Neotropic cormorant from two lagoons ofArgentina, to carry out both morphological and molecular studies by the 18S rDNAsequences, and to provide a phylogenetic hypothesis with the position of the genusOrnithocapillaria into Capillaridae. Thirty-seven adult Capillariinae nematodes extractedfrom different Phalacrocorax brasilianus individuals were examined morphologically,cleared in lactophenol, and studied with light and scanning electron microscopy. Inaddition, nuclear 18S rDNA parcial sequences were analyzed by the Bayesian Inferenceand Maximum Likelihood methods to evaluate phylogenetic relationships among the taxa.The new isolates of Ornithocapillaria spiculata n. comb. top matched sequences ofBaruscapillaria obsignata specimens and formed a well-supported clade. The geneticdistance between O. spiculata and B. obsignata is clearly observed in the consensus BI-ML tree. Also, the p-distance was 1.2-1.4% among both species. The cluster composed ofO. spiculata and B. obsignata is a sister group of another big clade which includes otherCapillariidae species. This work support the assignation of the species B. spiculata toOrnithocapillaria spiculata, and might be a new argument for justifying the creation ofthis latter genus for some species of Baruscapilllaria. The new isolates correspond to the first genetic characterization of specimens of the genus Ornithocapillaria.