title: A comparative study of Ligophorus uruguayense and L. saladensis (Monogenea: Ancyrocephalidae) from Mugil liza (Teleostei: Mugilidae) in southern Brazil.
abstract: Representatives of Ligophorus Euzet et Suriano, 1977 were found on the gills of Mugil liza Valenciennes caught in southern Brazil. They were identified as Ligophorus uruguayense Failla Siquier et Ostrowski de Núñez, 2009 and Ligophorus saladensis Marcotegui et Martorelli, 2009, even though specific identification proved to be difficult due to inconsistencies in some diagnostic features reported for these two species. Therefore, a combined morphological and molecular approach was used to critically review the validity of these species, by means of phase contrast and confocal fluorescence microscopical examination of sclerotised hard parts, and assessing the genetic divergence between L. saladensis, L. uruguayense and their congeners using rDNA sequences. The main morphological differences between the two species relate to the shape of the accessory piece of the penis and the median process of the ventral bar. The accessory piece in L. uruguayense is shorter than in L. saladensis, has a cylindrical, convex upper lobe and straight lower lobe (vs with the distal tip of the lower lobe turning away from the upper lobe in the latter species). The ventral bar has a V-shaped anterior median part in L. uruguayense (vs U-shaped in L. saladensis). The two species are suggested to be part of a species complex together with L. mediterraneus Sarabeev, Balbuena et Euzet, 2005. We recommend to generalise such comparative assessment of species of Ligophorus for a reliable picture of the diversity and diversification mechanisms within the genus, and to make full use of its potential as an additional marker for mullet taxonomy and systematics.
authors.affiliation: Empresa de Pesquisa Agropecuaria e Extensao Rural de Santa Catarina (Epagri), Campo Experimental de Piscicultura de Camboriu, Camboriu, Santa Catarina, Brasil;
authors.forename: Natalia C
authors.initials: NC
authors.lastname: Marchiori
authors.affiliation: Institut des Sciences de l'Evolution, IRD-CNRS-Universite Montpellier 2, Montpellier, France.|Present address: Institut de Recherche pour le Developpement (IRD), Yaounde, Cameroon.
authors.forename: Antoine
authors.initials: A
authors.lastname: Pariselle
authors.affiliation: Laboratory of Parasite Biology of Aquatic Organisms, Oceanographic Institute, Federal University of Rio Grande Foundation, Rio Grande, Rio Grande do Sul, Brazil;
authors.forename: Joaber
authors.initials: J
authors.lastname: Pereira
authors.affiliation: Institut des Sciences de l'Evolution, IRD-CNRS-Universite Montpellier 2, Montpellier, France;
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Agnese
authors.affiliation: Institut de Recherche pour le Developpement (IRD), University of Montpellier 2, Montpellier, France;
authors.forename: Jean-Dominique
authors.initials: JD
authors.lastname: Durand
authors.affiliation: Laboratory of Biodiversity and Evolutionary Genomics, Department of Biology, University of Leuven, Leuven, Belgium.|Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic.|Invertebrates Unit, Biology Department, Royal Museum for Central Africa, Tervuren, Belgium.|Institute of Marine Biological Resources and Inland Waters, Hellenic Centre for Marine Research, Anavyssos, Greece.
authors.forename: Maarten P M
authors.initials: MP
authors.lastname: Vanhove
keywords: molecular systematics; morphology; mullet; parasite; taxonomy