First Study on Gyrodactylus (Monogenea: Gyrodactylidae) in Morocco, with Description of a New Species from Luciobarbus pallaryi and Luciobarbus ksibi (Actinopterygii: Cyprinidae).

To date, 41 species of Gyrodactylus have been described from Africa. However, none of these have been reported in Morocco. After identifying and examining 738 cyprinid host specimens, 26 specimens belonging to Gyrodactylus were found to parasitize the gills of nine species of Luciobarbus, Carasobarbus, and Pterocapoeta. The current study provides new information about the presence of a new parasitic species in Morocco, the first to be characterized on a species level in the Maghreb region. It describes in detail 12 specimens of Gyrodactylus isolated from the gills of Luciobarbus pallaryi (Pellegrin, 1919) and Luciobarbus ksibi (Boulenger, 1905). Based on morphoanatomical observations, the characterization of the specimens collected indicates a species of Gyrodactylus that is new to science, described here as Gyrodactylus nyingiae n. sp. The new species is different from previously described gyrodactylids infecting African cyprinid hosts because it has a longer hamulus total length, a longer hamulus root, a downward projecting toe of the marginal hook, and a trapezium-shaped ventral bar membrane with a slightly striated median portion and small rounded anterolateral processes. This study increases the total number of Gyrodactylus spp. found in African cyprinids to four.

Monogeneans from Catfishes in Lake Tanganyika. II: New Infection Site, New Record, and Additional Details on the Morphology of the Male Copulatory Organ of Gyrodactylus transvaalensis Prudhoe and Hussey, 1977.

The ichthyofauna of Lake Tanganyika consists of 12 families of fish of which five belong to Siluriformes (catfishes). Studies on Siluriformes and their parasites in this lake are very fragmentary. The present study was carried out to help fill the knowledge gap on the monogeneans infesting the siluriform fishes of Lake Tanganyika in general and, more particularly, Clarias gariepinus. Samples of gills of Clarias gariepinus (Clariidae) were examined for ectoparasites. We identified the monogenean Gyrodactylus transvaalensis (Gyrodactylidae). This is the first time this parasite was found infecting gills. We are the first to observe a large spine in the male copulatory organ of this species and to provide measurements of its genital spines; this completes the description of the male copulatory organ, which is important in standard monogenean identification. This is the first monogenean species reported in C. gariepinus at Lake Tanganyika and the third known species on a representative of Siluriformes of this lake. It brings the total number of species of Gyrodactylus recorded in Lake Tanganyika to four. Knowing that other locations where this species has been reported are geographically remote from Lake Tanganyika, we propose a "failure to diverge" phenomenon for G. transvaalensis.

[Angiocholitis on hepatic hydatid cyst fistulised in the main bile duct: two case reports]. / Angiocholite sur kyste hydatique hépatique fistulisé dans la voie biliaire principale: à propos de 2 cas.

Hydatid cyst is a zoonosis that frequently affects the liver, which is endemic in several countries such as Morocco. The hepatic hydatidosis can be complicated by angiocholitis, currently, the treatment of choice is endoscopic retrograde cholangio-pancreatography with sphincterotomy. We report two clinical cases of angiocholitis on hepatic hydatid cyst fistulised in the main bile duct which were treated endoscopically with a favourable outcome. Early diagnosis and adequate management can improve the prognosis of these patients.

Metastatic rectal gastrointestinal stromal tumor with intestinal obstruction: A rare case report.

Gastrointestinal stromal tumors (GISTs) arising from the rectum are rare. We report the case of an aggressive rectal gastrointestinal stromal tumor (GIST) in a 60-year-old female that presented for symptoms of constipation and lower gastrointestinal bleeding. Upon rectal examination, a hard mass was found at 6cm from the anal marge. An MRI was indicated that shows a well-demarcated lesion originates from the distal rectum with exophytic growth and central necrosis. The diagnosis of rectal gist was confirmed by colonoscopy with biopsy and immunohistochemical analyses of bioptic material. Liver metastases were seen on computerized tomography (CT). She was referred for palliative chemotherapy. The patient had suffered from intestinal obstruction three weeks after his initial presentation and passed away shortly thereafter. We aimed to report this case as an aggressive and rare GIST localization.

Integrating morphological and molecular approaches for characterizing four species of Dactylogyrus (Monogenea: Dactylogyridae) from Moroccan cyprinids, with comments on their host specificity and phylogenetic relationships.

Cyprinid fishes are known to harbour highly host-specific gill-associated parasites of Dactylogyrus. High similarity in the morphology of sclerotized structures among Dactylogyrus species, especially those parasitizing congeneric cyprinoids, makes their identification difficult. In this paper, four previously known species of Dactylogyrus are characterized and illustrated under a reliable taxonomic framework integrating morphological and molecular evidence, and their phylogenetic relationships are investigated using molecular data. The species are as follows: D. borjensis from Luciobarbus zayanensis; D. draaensis from Luciobarbus lepineyi; D. ksibii from Luciobarbus ksibi and Luciobarbus rabatensis; and D. marocanus from Carasobarbus fritschii, L. ksibi, L. zayanensis and Pterocapoeta maroccana. Our results revealed intraspecific genetic variability among specimens of D. ksibii collected from two different hosts and geographically distant basins. Phylogenetic reconstruction showed that Dactylogyrus spp. parasitizing Moroccan cyprinids are representatives of three main lineages corresponding to morphological differences and host specificity. Our records of D. marocanus on L. zayanensis and P. maroccana increase the range of available host species i.e.,eight species of four cyprinid genera representing two phylogenetic lineages (i.e., Barbinae and Torinae).

Diversity and phylogeny of Paradiplozoon species (Monogenea: Diplozoidae) parasitising endemic cyprinoids in the peri-Mediterranean area, with a description of three new Paradiplozoon species.

The Diplozoidae are monogenean parasites of mainly cyprinoid fishes with a unique life cycle, whereby two larvae undergo anastomosis and fuse into a single cross-shaped specimen. Paradiplozoon is the most species rich and widespread genus of the family, with a distribution range covering Eurasia and Africa; however, some areas remain underexplored and their diplozoid fauna is uncertain. In the present study, the Paradiplozoon diversity was investigated in the peri-Mediterranean region, which has the highest levels of cyprinoid diversity and endemism in Europe. A total of 36 endemic cyprinoid species were sampled from sites in north-west Africa and the southern European peninsulas and investigated for the presence of diplozoid parasites. Of five Paradiplozoon species collected, three were identified as new to science: Paradiplozoon moroccoensis n. sp. from the Moroccan endemic Luciobarbus lepineyi; Paradiplozoon ibericus n. sp. from Iberian endemic cyprinids and leuciscids and Paradiplozoon helleni n. sp. from the Greek endemic Scardinius acarnicus and Tropidophoxinellus hellenicus (descriptions provided herein). In addition, new host records for P. homoion and P. megan are presented, with the former being most prevalent in the investigated region. Phylogenetic analysis supported paraphyly of the genus Paradiplozoon, and suggests the need for a careful taxonomic re-evaluation of this genus. Furthermore, the results showed that endemic Paradiplozoon of the peri-Mediterranean do not form a monophyletic group, suggesting multiple origins of this parasite groups in different peri-Mediterranean regions.

Disentangling the evolutionary history of peri-Mediterranean cyprinids using host-specific gill monogeneans.

The diversification of Mediterranean fish appears to be far more complex than could be explained by a single dispersion model. Cyprinids represent one of the most species-rich groups of freshwater fishes living in this region. The current distribution of several highly divergent cyprinid taxa is most likely the result of multiple dispersion events. Cyprinid fish serve as hosts for the highly diversified and host-specific monogenean parasites of the genus Dactylogyrus. On the assumption that the distribution of Dactylogyrus spp. reflects the biogeography and evolutionary history of their hosts, we used these parasites as an additional tool to shed new light on the evolutionary history of peri-Mediterranean cyprinids of the subfamily Barbinae. The degree of congruence between host and parasite phylogenies was investigated using 29 Dactylogyrus spp. and 34 Barbinae hosts belonging to the genera Aulopyge, Barbus and Luciobarbus. We showed that the morphological adaptation of Dactylogyrus (i.e. of the ventral bar, representing the most variable morphological character of the attachment organ) is linked with parasite phylogeny. By applying distance-based and event-based cophylogenetic approaches, we revealed a significant global coevolutionary signal. A total of 62% of individual host-parasite links contributed significantly to the coevolutionary structure evidenced between hosts of Barbus spp. and Iberian Luciobarbus spp., and their host-specific Dactylogyrus spp. The host switching of parasites was revealed as the most important coevolutionary event in the Dactylogyrus-Barbinae system in the peri-Mediterranean region. Cophylogenetic analyses and the mapping of the morphological character of the parasite attachment organ onto the phylogeny of Dactylogyrus indicate that endemic southern European Dactylogyrus spp. parasitizing cyprinids of Barbinae have multiple origins. We suggest that continental bridges connecting southern Europe and North Africa played a crucial role in the dispersion of cyprinids, affecting the distribution of their host-specific gill parasites.

Host-specific Dactylogyrus parasites revealing new insights on the historical biogeography of Northwest African and Iberian cyprinid fish.

BACKGROUND: Host specificity in parasites represents the extent to which a parasite's distribution is limited to certain host species. Considering host-specific parasites of primarily freshwater fish (such as gill monogeneans), their biogeographical distribution is essentially influenced by both evolutionary and ecological processes. Due to the limited capacity for historical dispersion in freshwater fish, their specific coevolving parasites may, through historical host-parasite associations, at least partially reveal the historical biogeographical routes (or historical contacts) of host species. We used Dactylogyrus spp., parasites specific to cyprinid fish, to infer potential historical contacts between Northwest African and European and Asian cyprinid faunas. Using phylogenetic reconstruction, we investigated the origin(s) of host-specific Dactylogyrus spp. parasitizing Northwest African and Iberian cyprinid species. RESULTS: In accordance with hypotheses on the historical biogeography of two cyprinid lineages in Northwest Africa, Barbini (Luciobarbus) and Torini (Carasobarbus), we demonstrated the multiple origins of Northwest African Dactylogyrus. Dactylogyrus spp. of Carasobarbus spp. originated from Asian cyprinids, while Dactylogyrus spp. of Luciobarbus spp. originated from European cyprinids. This indicates the historical Northern route of Dactylogyrus spp. dispersion to Northwest African Luciobarbus species rather than the Southern route, which is currently widely accepted for Luciobarbus. In addition, both Northwest African cyprinid lineages were also colonized by Dactylogyrus marocanus closely related to Dactylogyrus spp. parasitizing African Labeo spp., which suggests a single host switch from African Labeonini to Northwest African Luciobarbus. We also demonstrated the multiple origins of Dactylogyrus spp. parasitizing Iberian Luciobarbus species. One Iberian Dactylogyrus group was phylogenetically closely related to Dactylogyrus of Moroccan Carasobarbus, while the second was related to Dactylogyrus of Moroccan Luciobarbus. CONCLUSIONS: Our study confirms the different origins of two Northwest African cyprinid lineages. It suggests several independent historical contacts between European Iberian Luciobarbus and two lineages of Northwest African cyprinids, these contacts associated with host switches of Dactylogyrus parasites.

Four new species of Dactylogyrus Diesing, 1850 (Monogenea: Dactylogyridae) parasitising the gills of northern Moroccan Luciobarbus Heckel (Cyprinidae): morphological and molecular characterisation.

Four new species of Dactylogyrus Diesing, 1850 are described from the gills of three species of Luciobarbus Heckel collected from various hydrographical basins in northern Morocco: Dactylogyrus scorpius n. sp. from Luciobarbus rifensis Doadrio, Casal-Lopez & Yahyaoui; D. benhoussai n. sp. from L. moulouyensis Pellegrin; and D. varius n. sp. and D. falsiphallus n. sp. from L. maghrebensis Doadrio, Perea & Yahyaoui. The descriptions of the new species are confirmed by molecular data (partial 18S rDNA, ITS1, and partial 28S rDNA sequences). All four species belong to the group of Dactylogyrus species, possessing a cross-shaped ventral bar and a male copulatory organ composed of a loosely coiled copulatory tube and an accessory piece with a capsule-like base and recurved distal portion. Given the high shape variability of the haptoral anchors reported among specimens of D. varius n. sp., three morphological forms within this species (D. varius f. vulgaris, D. varius f. magnus, and D. varius f. dromedarius) are recognised. However, specimens belonging to D. benhoussai n. sp. and D. varius f. vulgaris were morphologically very similar and were discriminated with certainty, only when using molecular data.