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Purpose: To study the monogeneans gill parasites of Heterobranchus bidorsalis (Siluriformes, Clariidae) fish of economic interest in the Bagoue River. Methods: Fifty-five specimens of H. bidorsalis were caught with gillnets in the Bagoué River from August 2018 to January 2019. The monogeneans were individually isolated from the gill and transferred directly onto a slide in a drop of glycerin ammonium picrate mixture (GAP). Results: The new species differ from the previously described Quadriacanthus spp. mainly by the morphology of their sclerotised vagina: Quadriacanthus tanoyaoi sp. nov having a V-shaped, widely open vagina with a central protuberance, and Quadriacanthus bidorsalisi sp. nov having a pear-shaped vagina, composed of a tubular part with a ring near the aperture and a swollen portion. Q. tanoyaoi sp. nov and Q. bidorsalisi sp. nov are different in the shape of the dorsal and ventral anchors (more sturdy for Q. tanoyaoi), of the dorsal and ventral cuneus (triangular vs Y-shaped, respectively), and that of the vagina (V-shaped, widely open with a central protuberance vs pear-shaped, respectively). Conclusion: To date, only Quadriacanthus mandibulatus Francová & Řehulková, 2017 were recognised parasitizing from H. bidorsalis from the Nile River Basin (Sudan) and Lake Turkana (Kenya). The present study with the description of 2 new species expands the number to 3 species of monogeneans for this fish. [ABSTRACT FROM AUTHOR]

The group of large five-spotted Hemichromis species from West Africa and Lower Guinea was revised using an integrative approach combining morphometry (measurements, meristics and colour patterns) and genetics (cytochrome b gene). Specimens from 100 populations were sorted into three main groups on the basis of morphological criteria. Samples from Lake Bosumtwi clustered together with others from West Africa in a large well-supported clade (bootstrap values and posterior probabilities: 98/96/100), both in morphometric and genetic analyses, raising again the hypothesis of synonymy of H. frempongi with H. fasciatus. Samples from southern Lower Guinea, including the type locality (Gabon) of H. elongatus, constituted a second weakly resolved cluster (64/38/51), resulting from a potential admixture of populations of diverse origins which share common morphological traits. Populations from northern Lower Guinea (Atlantic coastal basins) and the upper Chad basin in Cameroon formed a third strongly supported clade (99/100/100), which corresponds to a new species, Hemichromis camerounensis sp. nov., herein described. [ABSTRACT FROM AUTHOR]

The goals of this paper were to investigate phylogenetic and evolutionary patterns of cichlid fish from West Africa and their Cichlidogyrus and Scutogyrus monogenean parasites, to uncover the presence of host-parasite cospeciation and to assess the level of morphological adaptation in parasites. This required the following steps, each one representing specific objectives of this paper: (1) to build phylogenetic trees for Cichlidogyrus and Scutogyrus species based on ribosomal DNA sequences, (2) to investigate phylogenetic relationships within West African cichlid fish based on the analysis of mitochondrial cytochrome b DNA sequences, (3) to investigate host-parasite cophylogenetic history to gain clues on parasite speciation process, and (4) to investigate the link between the morphology of the attachment apparatus and parasite phylogeny. Phylogenetic analyses supported the monophyletic origin of the Cichlidogyrus/Scutogyrus group, and suggested that Cichlidogyrus is polyphyletic and that Scutogyrus is monophyletic. The phylogeny of Cichlidae supported the separation of mouthbrooders and substrate-brooders and is consistent with the hypothesis that the mouthbrooding behavior of Oreochromis and Sarotherodon evolved from substrate-brooding behavior. The mapping of morphological characters of the haptor onto the parasite phylogenetic tree suggests that the attachment organ has evolved from a very simple form to a more complex one. The cophylogenetic analyses indicated a significant fit between trees using distancebased tests, but no significant cospeciation signal using tree-based tests, suggesting the presence of parasite duplications and host switches on related host species. This shed some light on the diversification process of Cichlidogyrus species parasitizing West African cichlids. [ABSTRACT FROM AUTHOR]