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African cichlids are model systems for evolutionary studies and host-parasite interactions, because of their adaptive radiations and because they harbour many species of monogenean parasites with high host-specificity. Five locations were sampled in southern Lake Victoria: gill-infecting monogeneans were surveyed from 18 cichlid species belonging to this radiation superflock and two others representing two older and distantly related lineages. We found one species of Gyrodactylidae, Gyrodactylus sturmbaueri Vanhove, Snoeks, Volckaert & Huyse, 2011, and seven species of Dactylogyridae. Four are described herein: Cichlidogyrus pseudodossoui n. sp., Cichlidogyrus nyanza n. sp., Cichlidogyrus furu n. sp., and Cichlidogyrus vetusmolendarius n. sp. Another Cichlidogyrus species is reported but not formally described (low number of specimens, morphological similarity with C. furu n. sp.). Two other species are redescribed: C. 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 others, highlighting the need to re-evaluate the current classification system 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 congeners that infect other haplochromines. Morphological traits indicate that representatives of Cichlidogyrus colonised Lake Victoria haplochromines or their ancestors at least twice, which is in line with the Lake Victoria superflock being colonised by two cichlid tribes (Haplochromini and Oreochromini).

A correction was made to the e-First version of this paper on 2 March 2022 prior to the final issue publication. The current online and print versions are identical and both contain the correction. Taxonomic bias, resulting in some taxa receiving more attention than others, has been shown to persist throughout history. Such bias in primary biodiversity data needs to be addressed because the data are vital to environmental management. This study reviews taxonomic bias in South African primary biodiversity data obtained from the Global Biodiversity Information Facility (GBIF). The focus was specifically on animal classes, and regression analysis was used to assess the influence of scientific interest and cultural salience on taxonomic bias. A higher resolution analysis of the two explanatory variables' influence on taxonomic bias is conducted using a generalised linear model on a subset of herpetofaunal families from the focal classes. Furthermore, the potential effects of cultural salience and scientific interest on a taxon's extinction risk are investigated. The findings show that taxonomic bias in South Africa's primary biodiversity data has similarities with global scale taxonomic bias. Among animal classes, there is strong bias towards birds while classes such as Polychaeta and Maxillopoda are under-represented. Cultural salience has a stronger influence on taxonomic bias than scientific interest. It is, however, unclear how these explanatory variables may influence the extinction risk of taxa. We recommend that taxonomic bias can be reduced if primary biodiversity data collection has a range of targets that guide (but do not limit) accumulation of species occurrence records per habitat. Within this range, a lower target of species occurrence records accommodates species that are difficult to detect. The upper target means occurrence records for any species are less urgent but nonetheless useful and thus data collection efforts can focus on species with fewer occurrence records. Key words: biodiversity hotspot, biomonitoring, conservation, surrogate species, taxonomic chauvinism. Il a ete demontre que le biais taxonomique, qui fait que certains taxons recoivent plus d'attention que d'autres, persiste a travers l'histoire. Ce type de biais dans les donnees primaires de biodiversite doit etre aborde, car ces donnees sont vitales pour la gestion de l'environnement. Cette etude examine le biais taxonomique dans les donnees primaires de biodiversite d'Afrique du Sud obtenues aupres du Global Biodiversity Information Facility (GBIF). L'accent est mis sur les classes d'animaux, et une analyse de regression est utilisee pour evaluer l'influence de l'interet scientifique et de la pregnance culturelle sur le biais taxonomique. Une analyse a plus haute resolution de l'influence des deux variables explicatives sur le biais taxonomique est menee a l'aide d'un modele lineaire generalise sur un sous-ensemble de familles herpetofauniques de classes focales. En outre, les effets potentiels de la pregnance culturelle et de l'interet scientifique sur le risque d'extinction d'un taxon sont etudies. Les resultats montrent que le biais taxonomique des donnees primaires sur la biodiversite en Afrique du Sud presente des similarites avec le biais taxonomique a l'echelle mondiale. Parmi les classes d'animaux, il existe un fort biais en faveur des oiseaux, tandis que des classes telles que les Polychaeta et les Maxillopoda sont sous-representees. La pregnance culturelle a une plus grande influence sur le biais taxonomique que l'interet scientifique. Cependant, la maniere dont ces variables explicatives peuvent influencer le risque d'extinction des taxons n'est pas claire. Les auteurs recommandent que le biais taxonomique puisse etre reduit si la collecte de donnees primaires sur la biodiversite est assortie d'une serie de cibles qui guident (sans la limiter) l'accumulation d'enregistrements d'occurrence d'especes par habitat. a l'interieur de cette fourchette, une cible inferieure de releves d'occurrence d'especes permet de prendre en compte les especes difficiles a detecter. La cible superieure signifie que les releves d'occurrence d'une espece sont moins urgents, mais neanmoins utiles et que les efforts de collecte de donnees peuvent donc se concentrer sur les especes ayant moins de releves d'occurrence. [Traduit par la Redaction] Mots-cles : point nevralgique de la biodiversite, biosurveillance, conservation, especes substitutives, chauvinisme taxonomique., Background Primary biodiversity data reflects the knowledge and practices in the study of biodiversity (Troudet et al. 2017) and consists of species occurrence records (Soberon and Peterson 2004). These occurrence [...]

Dinoflagellates belonging to the genus Hematodinium are key parasites of marine crustaceans, primarily decapods. In this study, we document the first report of H. perezi Chatton & Poisson, 1930 on the African Atlantic coast. This is also the first parasite record in the invasive non-native Atlantic blue crab Callinectes sapidus Rathbun, 1896 in Morocco. Specimens of C. sapidus were sampled in winter 2023 from two Ramsar sites on the Moroccan Atlantic, namely Merja Zerga and Oualidia Lagoons, and were screened to detect the presence of parasites in their hemolymph. Based on staining fresh hemolymph smears, we did not detect Hematodinium in any of the 36 investigated individuals (20 and 16 from Merja Zerga and Oualidia Lagoons, respectively), probably due to methodological artifacts. The PCR-based method was revealed to be more accurate in diagnosing the Hematodinium parasite. It showed that at Merja Zerga Lagoon, 13 individuals of C. sapidus were infected by the parasite (prevalence: 65%) in comparison to four at Oualidia Lagoon (25%). Genetic analysis, based on the ITS1 rDNA gene from Hematodinium, confirmed the sequences as being those of Hematodinium perezi. [ABSTRACT FROM AUTHOR]

Owing to the largely unexplored diversity of metazoan parasites, their speciation mechanisms and the circumstances under which such speciation occurs – in allopatry or sympatry – remain vastly understudied. Cichlids and their monogenean flatworm parasites have previously served as a study system for macroevolutionary processes, e.g., for the role of East African host radiations on parasite communities. Here, we investigate the diversity and evolution of the poorly explored monogeneans infecting a West and Central African lineage of cichlid fishes: Chromidotilapiini, which is the most species-rich tribe of cichlids in this region. We screened gills of 149 host specimens (27 species) from natural history collections and measured systematically informative characters of the sclerotised attachment and reproductive organs of the parasites. Ten monogenean species (Dactylogyridae: Cichlidogyrus and Onchobdella) were found, eight of which are newly described and one redescribed herein. The phylogenetic positions of chromidotilapiines-infecting species of Cichlidogyrus were inferred through a parsimony analysis of the morphological characters. Furthermore, we employed machine learning algorithms to detect morphological features associated with the main lineages of Cichlidogyrus. Although the results of these experimental algorithms remain inconclusive, the parsimony analysis indicates that West and Central African lineages of Cichlidogyrus and Onchobdella are monophyletic, unlike the paraphyletic host lineages. Several instances of host sharing suggest occurrences of intra-host speciation (sympatry) and host switching (allopatry). Some morphological variation was recorded that may also indicate the presence of species complexes. We conclude that collection material can provide important insights on parasite evolution despite the lack of well-preserved DNA material.

The Lower Congo Basin is characterized by a mangrove-lined estuary at its mouth and, further upstream, by many hydrogeographical barriers such as rapids and narrow gorges. Five localities in the mangroves and four from (upstream) left bank tributaries or pools were sampled. On the gills of Coptodon tholloni, Coptodon rendalli, Hemichromis elongatus, Hemichromis stellifer and Tylochromis praecox, 17 species of parasites (Dactylogyridae & Gyrodactylidae, Monogenea) were found, eight of which are new to science. Six of these are herein described: Cichlidogyrus bixlerzavalai n. sp. and Cichlidogyrus omari n. sp. from T. praecox, Cichlidogyrus calycinus n. sp. and Cichlidogyrus polyenso n. sp. from H. elongatus, Cichlidogyrus kmentovae n. sp. from H. stellifer and Onchobdella ximenae n. sp. from both species of Hemichromis. On Cichlidogyrus reversati a ridge on the accessory piece was discovered that connects to the basal bulb of the penis. We report a putative spillback effect of the native parasites Cichlidogyrus berradae, Cichlidogyrus cubitus and Cichlidogyrus flexicolpos from C. tholloni to the introduced C. rendalli. From our results, we note that the parasite fauna of Lower Congo has a higher affinity with the fauna of West African and nearby freshwater ecoregions than it has with fauna of other regions of the Congo Basin and Central Africa.