Cryptic diversity, characterized by morphologically similar but genetically distinct species, poses significant challenges to traditional taxonomic methods. Within monogeneans parasitizing northwest African barbels, this complexity hampers species identification, limiting our understanding of diversity, distribution and evolutionary relationships. Supported by previously published genetic data, we morphologically delineate herein 9 Gyrodactylus species from Morocco. Newly described species include G. agnesei sp. nov. and G. benhoussai sp. nov. from Luciobarbus rabatensis, with the latter also found on Carasobarbus fritschii, and both G. deburonae sp. nov. and G. marruecosi sp. nov. from L. massaensis. Additionally, G. diakini sp. nov. and G. louiziae sp. nov. were identified from L. rifensis and L. yahyaouii, respectively. Pterocapoeta maroccana harboured G. pterocapoetai sp. nov., morphologically resembling G. shigoleyae sp. nov. from sympatric L. zayanensis. We also examined taxonomical discrepancies between Gyrodactylus species from L. ksibi and L. pallaryi, evaluated the status of previously described G. nyingiae and described G. qninbai sp. nov. from L. ksibi. Our findings highlight the conservative morphology in northwest African Gyrodactylus, characterized by an ancestral median ridge in the ventral bar membrane, similar to that found in species from Eurasia. Subtle phenotypic features, like bifurcations in dorsal bars and proportions of marginal hooks, serve as diagnostic traits. We further evidenced a potential host-switching event from northwest African to Iberian hosts, correlating with the region's geological history and cyprinid dispersal events during intermittent closures of the Strait of Gibraltar. These insights illuminate the complex evolutionary processes driving gyrodactylid diversification in the West Mediterranean.
- Keywords
- Morocco, Southwest Mediterranean, cyprinids, gyrodactylids, monogenea,
- MeSH
- Cyprinidae * parasitology MeSH
- Phylogeny MeSH
- Trematode Infections * veterinary parasitology epidemiology MeSH
- Fish Diseases * parasitology epidemiology MeSH
- Trematoda * classification anatomy & histology genetics MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Morocco epidemiology MeSH
The freshwaters of Iraq harbour a high diversity of endemic and phylogenetically unique species. One of the most diversified fish groups in this region is cyprinoids, and although their distribution is relatively well known, their monogenean parasites have only rarely been investigated. Herein, we applied an integrative approach, combining morphology with molecular data, to assess the diversity and phylogeny of cyprinoid-associated monogenean parasites. A total of 33 monogenean species were collected and identified from 13 endemic cyprinoid species. The highest species diversity was recorded for Dactylogyrus (Dactylogyridae, 16 species) and Gyrodactylus (Gyrodactylidae, 12 species). Four species of Dactylogyrus and 12 species of Gyrodactylus were identified as new to science and described. Two other genera, Dogielius (Dactylogyridae) and Paradiplozoon (Diplozoidae), were represented only by 4 and 1 species, respectively. Phylogenetic analyses of the Dactylogyrus and Gyrodactylus species revealed that the local congeners do not form a monophyletic group and are phylogenetically closely related to species from other regions (i.e. Europe, North Africa and Eastern Asia). These findings support the assumption that the Middle East served as an important historical crossroads for the interchange of fauna between these 3 geographic regions.
- Keywords
- Cyprinoidei, Dactylogyrus, Dogielius, Gyrodactylus, Middle East, Paradiplozoon, phylogeny, species diversity,
- MeSH
- Phylogeny MeSH
- Fishes MeSH
- Trematoda * genetics MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Iraq epidemiology MeSH
- Africa, Northern MeSH
- Middle East MeSH
This study reports on three species of Dactylogyrus Diesing, 1850 (Dactylogyridae) collected from tinfoil barb, Barbonymus schwanenfeldii (Bleeker) which were imported into South Africa as ornamental fish from Sri Lanka and Thailand. Supplementary morphometric characterisation and molecular data (partial 18S and 28S rDNA, and ITS1 region sequences) are presented for Dactylogyrus lampam (Lim & Furtado, 1986), Dactylogyrus tapienensis Chinabut & Lim, 1993 and Dactylogyrus viticulus Chinabut & Lim, 1993. Prevalence of Dactylogyrus spp. infection was 87% and 80% for fish from Sri Lanka and Thailand, respectively. Composition of the parasites between the fish of each origin differed. All three species were found to infect fish from Thailand, but only D. lampam was present on the fish received from Sri Lanka. Phylogenetic analysis revealed the position of studied species, with D. lampam clustering within the lineages of varicorhini-type species, while D. tapienensis and D. viticulus form a sister lineage to Dactylogyrus spp. associated with Cyprinus carpio L. and Carassius spp., species parasitising central African large cyprinids (Labeo Cuvier), and species parasitising African and Middle Eastern Carasobarbus spp.
TITLE: Dactylogyrus spp. (Dactylogyridae, Monogenea) de Barbonymus schwanenfeldii importé en Afrique du Sud : caractérisation morphométrique et moléculaire. ABSTRACT: Cette étude porte sur trois espèces de Dactylogyrus Diesing, 1850 (Dactylogyridae), prélevées sur des Barbonymus schwanenfeldii (Bleeker) qui ont été importés en Afrique du Sud comme poissons d’ornement depuis le Sri Lanka et la Thaïlande. Une caractérisation morphométrique et des données moléculaires supplémentaires (ADNr 18S et 28S partiels et séquences de la région ITS1) sont présentées pour Dactylogyrus lampam (Lim & Furtado, 1986), Dactylogyrus tapienensis Chinabut & Lim, 1993 et Dactylogyrus viticulus Chinabut & Lim, 1993. La prévalence de l’infection par les Dactylogyrus spp. était respectivement de 87 % et 80 % pour les poissons du Sri Lanka et de Thaïlande. La composition des parasites entre les poissons des deux origines différait. Les trois espèces infectaient les poissons de Thaïlande, mais seul D. lampam était présent sur les poissons du Sri Lanka. L’analyse phylogénétique a révélé la position des espèces étudiées, D. lampam se regroupant dans les lignées d’espèces de type varicorhini, tandis que D. tapienensis et D. viticulus forment une lignée sœur des Dactylogyrus spp. associés à Cyprinus carpio L. et Carassius spp., espèces parasitant les grands cyprinidés d’Afrique centrale (Labeo Cuvier), et espèces parasitant les Carasobarbus spp. d’Afrique et du Moyen-Orient.
- Keywords
- Barbonymus, Dactylogyrus, Monogenea, Ornamental fish, South Africa,
- Publication type
- Journal Article MeSH
Diplozoidae are common monogenean ectoparasites of cyprinoid fish, with the genus Paradiplozoon being the most diversified. Despite recent studies on Diplozoidae from Europe, Africa and Asia, the diversity, distribution and phylogeny of this parasite group appears to be still underestimated in the Middle East. The objective of this study was to investigate the diversity, endemism and host specificity of diplozoids parasitizing cyprinoid fish from the Middle East, considering this region as an important historical interchange of fish fauna, and to elucidate the phylogenetic position of Middle Eastern Paradiplozoon species within Diplozoidae. Four Paradiplozoon species were collected from 48 out of 94 investigated cyprinoid species. Three known species, Paradiplozoon homoion, Paradiplozoon bliccae and Paradiplozoon bingolensis, were recorded on new cyprinoid host species, and a new species, Paradiplozoon koubkovae n. sp., was recorded on Luciobarbus capito and Capoeta capoeta from the Caspian Sea basin in Iran and Turkey. Paradiplozoon bliccae, exhibiting a wide host range in the Middle East, expressed both morphological and genetic intraspecific variabilities. The four Paradiplozoon species collected in the Middle East were placed in divergent clades, showing the rich evolutionary history of diplozoid parasites in the Middle East. Our study also revealed that two lineages of African diplozoids have a Middle Eastern origin. We stress the importance of applying an integrative approach combining morphological, ecological and molecular methods to reveal the real diversity of diplozoids.
- Keywords
- Cyprinoidei, evolutionary history, host specificity, parasite fauna, phylogeography,
- MeSH
- Biological Evolution MeSH
- Cyprinidae * MeSH
- Phylogeny MeSH
- Trematoda * genetics MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Turkey epidemiology MeSH
BACKGROUND: Monogenea (Platyhelminthes, Neodermata) are the most species-rich class within the Neodermata superclass of primarily fish parasites. Despite their economic and ecological importance, monogenean research tends to focus on their morphological, phylogenetic, and population characteristics, while comprehensive omics analyses aimed at describing functionally important molecules are few and far between. We present a molecular characterisation of monogenean representative Eudiplozoon nipponicum, an obligate haematophagous parasite infecting the gills of the common carp. We report its nuclear and mitochondrial genomes, present a functional annotation of protein molecules relevant to the molecular and biochemical aspect of physiological processes involved in interactions with the fish hosts, and re-examinate the taxonomic position of Eudiplozoon species within the Diplozoidae family. RESULTS: We have generated 50.81 Gbp of raw sequencing data (Illumina and Oxford Nanopore reads), bioinformatically processed, and de novo assembled them into a genome draft 0.94 Gbp long, consisting of 21,044 contigs (N50 = 87 kbp). The final assembly represents 57% of the estimated total genome size (~ 1.64 Gbp), whereby repetitive and low-complexity regions account for ~ 64% of the assembled length. In total, 36,626 predicted genes encode 33,031 proteins and homology-based annotation of protein-coding genes (PCGs) and proteins characterises 14,785 (44.76%) molecules. We have detected significant representation of functional proteins and known molecular functions. The numbers of peptidases and inhibitors (579 proteins), characterised GO terms (16,016 unique assigned GO terms), and identified KEGG Orthology (4,315 proteins) acting in 378 KEGG pathways demonstrate the variety of mechanisms by which the parasite interacts with hosts on a macromolecular level (immunomodulation, feeding, and development). Comparison between the newly assembled E. nipponicum mitochondrial genome (length of 17,038 bp) and other diplozoid monogeneans confirms the existence of two distinct Eudiplozoon species infecting different fish hosts: Cyprinus carpio and Carassius spp. CONCLUSIONS: Although the amount of sequencing data and characterised molecules of monogenean parasites has recently increased, a better insight into their molecular biology is needed. The E. nipponicum nuclear genome presented here, currently the largest described genome of any monogenean parasite, represents a milestone in the study of monogeneans and their molecules but further omics research is needed to understand these parasites' biological nature.
- Keywords
- Annotation, Assembly, Genome, Helminths, Host–parasite interaction, Illumina, Mitochondrial genome, Monogenea, Nanopore, Sequencing,
- MeSH
- Phylogeny MeSH
- Genomics MeSH
- Carps * genetics MeSH
- Parasites * MeSH
- Trematoda * MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
Dactylogyrus Diesing, 1850 is the most species-rich genus in Platyhelminthes, with over 900 documented species, that are mostly strictly specific to freshwater cyprinoids. The morphological Dactylogyrus groups afrobarbae-type, carpathicus-type, pseudoanchoratus-type, and varicorhini-type are known to occur in Africa. This study describes a new species of Dactylogyrus of the varicorhini-type from the gills of the endemic smallmouth yellowfish Labeobarbus aeneus (Burchell) from the Vaal River, Free State Province, South Africa. Dactylogyrus matlopong sp. n. is unique among its varicorhini-type congeners mainly by the accessory piece of the male copulatory complex that presents a hook-shaped subunit with defined round base not reaching the male copulatory organ, combined with the presence of a conspicuous medial projection on the anterior margin of the ventral bar. Sequences of the partial 28S and 18S rRNA genes, together with entire ITS1 region, were generated for the first time for a species of Dactylogyrus from South Africa. Concatenated phylogenetic analyses of selected Dactylogyrus spp. showed that these parasites group according to their morphological types.
- Keywords
- ITS1 region, Key-words: yellowfish, new species, ribosomal genes, taxonomy,
- MeSH
- Cyprinidae * parasitology MeSH
- Phylogeny MeSH
- Fish Diseases * epidemiology parasitology MeSH
- Platyhelminths * genetics MeSH
- Trematoda * MeSH
- Gills parasitology MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- South Africa MeSH
BACKGROUND: Freshwater fauna of the Middle East encompass elements shared with three continents-Africa, Asia, and Europe-and the Middle East is, therefore, considered a historical geographic crossroad between these three regions. Even though various dispersion scenarios have been proposed to explain the current distribution of cyprinids in the peri-Mediterranean, all of them congruently suggest an Asian origin for this group. Herein, we investigated the proposed scenarios using monogenean parasites of the genus Dactylogyrus, which is host-specific to cyprinoid fishes. METHODS: A total of 48 Dactylogyrus species parasitizing cyprinids belonging to seven genera were used for molecular phylogenetic reconstruction. Taxonomically important morphological features, i.e., sclerotized elements of the attachment organ, were further evaluated to resolve ambiguous relationships between individual phylogenetic lineages. For 37 species, sequences of partial genes coding 18S and 28S rRNA, and the ITS1 region were retrieved from GenBank. Ten Dactylogyrus species collected from Middle Eastern cyprinoids and D. falciformis were de novo sequenced for the aforementioned molecular markers. RESULTS: The phylogenetic reconstruction divided all investigated Dactylogyrus species into four phylogenetic clades. The first one encompassed species with the "varicorhini" type of haptoral ventral bar with a putative origin linked to the historical dispersion of cyprinids via the North African coastline. The second clade included the majority of the investigated species parasitizing various phylogenetically divergent cyprinid hosts. The morphological and molecular data suggest the ancestral diversification of the species of this clade into two groups: (1) the group possessing the haptoral ventral bar of the "cornu" type, and (2) the group possessing the "wunderi" type. Dactylogyrus diversification apparently occurred in the Middle East, which is indicated by the presence of species with all morphotypes in the region. The last two clades included species parasitizing cyprinids with an East Asian origin, and species possessing the "magnihamatus" type of ventral bar. CONCLUSIONS: The molecular data suggest that some morphological characters of host-specific parasites may undergo convergent evolution in the divergent lineages, and therefore, to fully resolve the phylogenetic relationships among host-specific parasites, an integrative approach combining morphological and molecular data is still needed. In addition, our study indicates that parasite diversity in many regions is still under-explored, and thus we highlight the importance of studies of host-associated parasites, especially in the context of freshwater fish biogeography.
- Keywords
- Cyprinoidei, Historical dispersion, Parasites, Phylogeography, Platyhelminthes,
- MeSH
- Biodiversity MeSH
- Cyprinidae parasitology MeSH
- Phylogeny MeSH
- Host Specificity * MeSH
- Fish Diseases parasitology MeSH
- Platyhelminths anatomy & histology classification genetics physiology MeSH
- Fresh Water MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Africa MeSH
- Asia MeSH
- Europe MeSH
- Middle East MeSH
