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Pariselle, A.

Publications and source records attributed to Pariselle, A..

2 recordsLinked to original sources
bioRxiv2021

Somewhere I Belong: Phylogenetic Comparative Methods and Machine Learning to Investigate the Evolution of a Species-Rich Lineage of Parasites

AO_SCPLOWBSTRACTC_SCPLOWA substantial portion of biodiversity evolved through adaptive radiation. However, the effects of explosive speciation on species interactions remain poorly understood. Metazoan parasites infecting radiating host lineages could improve our knowledge because of their intimate host relationships. Yet limited molecular, phenotypic, and ecological data discourage multivariate analyses of evolutionary patterns and encourage the use of discrete characters. Here, we assemble new molecular, morphological, and host range data widely inferred from a species-rich lineage of parasites (Cichlidogyrus, Platyhelminthes: Monogenea) infecting cichlid fishes to address data scarcity. We infer a multi-marker (28S/18S rDNA, ITS1, COI mtDNA) phylogeny of 58/137 species and characterise major lineages through synapomorphies inferred from mapping morphological characters. We predict the phylogenetic position of species without DNA data through shared character states, a combined molecular-morphological phylogenetic analysis, and a classification analysis with support vector machines. Based on these predictions and a cluster analysis, we assess the systematic informativeness of continuous characters, search for continuous equivalents for discrete characters, and suggest new characters for morphological traits not analysed to date. We also model the attachment/reproductive organ and host range evolution using the data of 136/137 described species and multivariate phylogenetic comparative methods (PCMs). We show that discrete characters can mask phylogenetic signals but can be key for characterising species groups. Regarding the attachment organ morphology, a divergent evolutionary regime for at least one lineage was detected and a limited morphological variation indicates host and environmental parameters affecting its evolution. However, moderate success in predicting phylogenetic positions, and a low systematic informativeness and high multicollinearity of morphological characters call for a revaluation of characters included in species characterisations.

evolutionary biology↗
bioRxiv2021

Four new species of Cichlidogyrus (Platyhelminthes, Monogenea, Dactylogyridae) from Lake Victoria haplochromine cichlid fishes, with the redescription of C. bifurcatus and C. longipenis

African cichlids are model systems for evolutionary studies and for host-parasite interactions, because of their adaptive radiations and because they harbour many species of monogenean parasites with high host-specificity. Here, we sampled five locations in southern Lake Victoria, the youngest of the African Great Lakes. We surveyed gillinfecting monogeneans from 18 cichlid species belonging to the Lake Victoria radiation superflock and two cichlid species representing two older and distantly related lineages. We found one species of Gyrodactylus (Gyrodactylidae, Monogenea), Gyrodactylus sturmbaueri Vanhove, Snoeks, Volckaert & Huyse, 2011, and seven species of Cichlidogyrus (Dactylogyridae, Monogenea). Four species are herein described: Cichlidogyrus pseudodossoui n. sp., C. nyanza n. sp., C. furu n. sp., C. vetusmolendarius n. sp.. Another species is reported but not formally described (because of few specimens and morphological similarity with C. furu n. sp.). Two other species are redescribed: Cichlidogyrus bifurcatus Paperna, 1960 and C. longipenis Paperna & Thurston, 1969. Our results confirm that the monogenean fauna of Victorian littoral cichlids displays lower species richness and lower host-specificity than that of Lake Tanganyika littoral cichlids. In C. furu n. sp., hooks V are clearly longer than the other hooks, highlighting the need to re-evaluate the current classification system of haptoral configurations that considers hook pairs III-VII as rather uniform. Some morphological features of C. bifurcatus, C. longipenis and C. nyanza n. sp. suggest that these are closely related to other congeners that infect haplochromines. We also found morphological indications that representatives of Cichlidogyrus colonised Lake Victoria haplochromines or their ancestors at least twice, which is in line with the Lake Victoria superflock being colonized by two cichlid tribes (Haplochromini and Oreochromini). DisclaimerThis preprint is disclaimed for purposes of Zoological Nomenclature in accordance with the International Code of Zoological Nomenclature, Fourth Edition Articles 8.2 and 8.3 (ICZN 1999). No new names or nomenclatural changes are available from statements in this preprint. Resume - Quatre especes nouvelles de Cichlidogyrus (Platyhelminthes, Monogenea, Dactylogyridae) parasites dhaplochromine (Cichlidae) du lac Victoria, avec la redescription de C. bifurcatus and C. longipenisA cause des radiations adaptatives quils ont subies, les cichlides africain sont des systemes modeles pour etudier levolution, mais aussi les relations hotes/parasites, car ils hebergent de nombreuses especes de Monogenes parasites qui presentent une specificite etroite vis-a-vis de leurs hotes. Dans ce travail, nous avons echantillonne cinq localites dans le Sud du lac Victoria, le plus jeune des grands lacs dAfrique de lEst. Nous avons examine les Monogenes presents sur les branchies de 18 especes de Cichlides appartenant a la radiation adaptative << superflock >> du lac Victoria et de deux especes representant deux lignees anciennes et non etroitement apparentees. Nous avons trouve une espece de Gyrodactylus (Gyrodactylidae, Monogenea), Gyrodactylus sturmbaueri Vanhove, Snoeks, Volckaert & Huyse, 2011 et sept especes de Cichlidogyrus (Dactylogyridae, Monogenea). Quatre especes nouvelles sont decrites dans le present travail : Cichlidogyrus pseudodossoui n. sp., C. nyanza n. sp., C. furu n. sp., C. vetusmolendarius n. sp.. Une est signalee mais non decrite formellement (trop peux dindividus recueillis, morphologiquement proche de C. furu n. sp.). Deux autres sont redecrites : Cichlidogyrus bifurcatus Paperna, 1960 and C. longipenis Paperna & Thurston, 1969. Nos resultats confirment que la faune des Monogenes des Cichlides du lac Victoria fait preuve dune richesse specifique et dune specificite moins importante que celle du lac Tanganyika. Chez C. furu n. sp. la paire de crochet V etant nettement plus longue que les autres, il faudra reconsiderer le systeme de classification actuel des types de hapteurs chez les Cichlidogyrus, qui considere que tous les crochets (III a VII) ont la meme taille. Quelques caracteristiques morphologiques de C. bifurcatus, C. longipenis et C. nyanza n. sp. pourraient etre la preuve dune ascendance commune avec des congeneres presents chez dautres Haplochromines. De meme, certains caracteres indiqueraient que des representants des Cichlidogyrus ont colonise les Haplochromines du lac Victoria, ou leurs ancetres, au moins a deux reprises, ce qui est coherent avec une colonisation du lac par deux lignees de cichlides distinctes (Haplochromini and Oreochromini).

zoology↗