Host-parasite association of Placobdella costata (Glossiphoniidae: Hirudinea) and Mauremys leprosa (Geoemydidae: Testudinoidea) in aquatic ecosystems of Morocco

Enteric parasites in free-living Mediterranean pond turtle (Mauremys leprosa leprosa) in contrasted areas (natural vs polluted) from central-western of Morocco

The objective of this study is to assess the occurrence of intestinal parasites in Mediterranean pond turtle Mauremys leprosa leprosa collected from three contrasting environments in Morocco. Stool samples from 92 turtles were examined for parasite detection and enumeration. The identified intestinal parasites belong to helminths (oxyurids and ascarid) and protozoa (Entamoebidae). A total of 25 turtles (27.17%) were found to be infected by helminths and/or protozoan parasites. No adult form of these parasites was detected. Eggs of oxyurid and ascarid were detected in individuals of populations studied from Oued Ksob (23.07% and 30.76% of n = 13 turtles) and Oued Zat (34.14% and 24.39% of n = 41 turtles), respectively. For protozoa, Entamoeba cysts were present in turtles in Oued Ksob (15.38% of n = 13 turtles), Oued Zat (12.19% of n = 41 turtles), and Oued Tensift (5.26% of n = 38 turtles) localities. Oxyurid eggs showed the highest intensity at Oued Zat reaching 29.30 ± 59.59 eggs per gram (EPG), versus 12 ± 0.38 EPG for ascaris eggs in Oued Ksob. Entamoeba cysts were detected in lower levels with a maximum of 1.66 ± 1.50 cysts per gram (CPG), in Oued Zat. The prevalence of turtles eliminating eggs was statistically significant between localities for different parasite groups. This study reports for the first time a parasitological characterization of gastrointestinal parasites in wild populations of M. leprosa leprosa from contrasting environments, suggesting a relationship between turtles' infestation and the quality of their habitat.

Molecular Phylogenies of Leeches and Haemoparasites Infecting Freshwater Turtles in Aquatic Ecosystems of Northern Africa Suggest Phylogenetic Congruence between Placobdella costata Sensu Lato and Haemogregarina stepanowi Sensu Lato

Haemogregarines are blood parasites with a life-cycle involving a vertebrate as the intermediate host and an invertebrate as the definitive host and vector. Extensive phylogenetic investigations based on 18S-rRNA gene sequences have shown that Haemogregarina stepanowi (Apicomplexa: Haemogregarinidae) is able to infest a large diversity of freshwater turtle species, including the European pond turtle Emys orbicularis, the Sicilian pond turtle Emys trinacris, the Caspian turtle Mauremys caspica, the Mediterranean pond turtle Mauremys leprosa, and the Western Caspian turtle Mauremys rivulata, among others. From the same molecular markers, H. stepanowi is further considered to be a complex of cryptic species predisposed to infect the same host species. While Placobdella costata is known to be the unique vector of H. stepanowi, it is only recently that independent lineages within P. costata have been illustrated-suggesting the presence of at least five unique leech species across Western Europe. The aims of our study were therefore to investigate from mitochondrial markers (COI) the genetic diversity within haemogregarines and leeches infecting freshwater turtles of the Maghreb, in order to identify processes of parasite speciation. We showed that H. stepanowi consists of at least five cryptic species in the Maghreb, while two Placobella species were identified in the same area. Although an Eastern-Western speciation pattern was apparent for both leeches and haemogregarines, we cannot make definitive conclusions regarding co-speciation patterns between parasites and vectors. However, we cannot reject the hypothesis of a very strict host-parasite specificity within leeches.

Molecular Screening of Haemogregarine Hemoparasites (Apicomplexa: Adeleorina: Haemogregarinidae) in Populations of Native and Introduced Pond Turtles in Eastern Europe

Haemogregarines (Apicomplexa: Adeleorina) are the most common and widespread reptilian blood parasites. Haemogregarina stepanowi was the first haemogregarine described from a reptile, the European pond turtle Emys orbicularis, and initial assessments indicated it was widespread across different pond turtle host species across much of Europe, the Middle East and North Africa. However, recent molecular assessments have indicated the presence of multiple genetically distinct forms in North Africa and the Iberian Peninsula, and extensive mixed infections which may be associated with a negative impact on the hosts. Here, we screened two native species, E. orbicularis and Mauremys rivulata, and the introduced Trachemys scripta from Serbia and North Macedonia for haemogregarines by amplifying and sequencing part of the 18S rRNA gene of these parasites, and used a standard DNA barcoding approach to identify leeches, the final host, attached to pond turtles. Our results again demonstrate the occurrence of considerable diversity of parasites in the analysed pond turtle species, and that T. scripta are likely infected by local haemogregarine parasites, and not those that are found in its native range. Leeches were identified as Placobdella costata, part of a lineage from Northern Europe. Mixed infections within pond turtles were again common. Current haemogregarine taxonomy does not reflect the genetic diversity identified, and a full taxonomic reassessment is needed.

Composition and structure of the parasitic fauna of Hypostomus spp. (Loricariidae: Hypostominae) from a Neotropical river in Brazil

Hypostomus are abundant in Brazilian rivers and streams. In the Ivaí River, the loricariids represent 20.3% of the total species of the basin. Of these 13 species belong to Hypostomus. However, to date, there are no studies on these fish parasitic fauna. Thus, this research aimed to analyze the distribution of the parasitic infracommunity of six species of Hypostomus from the Ivaí River and investigate how the infracommunity is structured in these hosts. One hundred and twenty-eight fish were analyzed, belonging to six sympatric species of Hypostomus (Hypostomus hermanni, H. cochliodon, H. albopunctatus, H. regani, Hypostomus sp.1, and Hypostomus sp.2); of these, 92.9% were parasitized with at least one taxon, totaling 1478 specimens of parasites. The parasitic fauna was composed of the ectoparasites Trinigyrus anthus, T. carvalhoi, Unilatus unilatus (monogeneans), and Placobdella spp. (hirudinea), and the endoparasites Austrodiplostomum compactum (digenean) and Procamallanus annipetterae (nematode). The parasites exhibited similar patterns of infection in all hosts, including a low number of species, low diversity, and numerical dominance of a group of parasites. However, permutational multivariate analysis of variance (PERMANOVA) showed different parasite species compositions among the hosts. Hypostomus cochliodon and H. regani had the highest parasite richness, while Hypostomus sp.1 and Hypostomus sp.2 showed low abundance and intensity of parasitic infections. However, Hypostomus sp.1 showed the highest values of evenness, although the parasite composition in both species did not differ. The results presented herein contribute to increasing the knowledge about the parasitic fauna of Hypostomus spp. from the Ivaí River by presenting new hosts and locality records.

Sucking of human blood by Placobdella costata (O. F. Müller, 1846) (Hirudinida: Glossiphoniidae): Case study with notes on body form

Four events of Placobdella costata sucking human blood are described.Human blood was sucked by both adult and juvenile specimens of P. costata.The feeding strategies of juveniles under parental care are presented.New data on juvenile specimens' body form are presented.Information on the potential role of mammals in dispersion and habitat preferences of leeches P. costata is considered.

Putative intranuclear coccidium in Mauremys leprosa (Schweigger) from Morocco

Although intranuclear coccidiosis was first identified in chelonians less than 30 years ago, it is now considered an important emerging disease. Symptoms include anorexia, weakness and weight loss, potentially leading to death of the infected animal. The use of molecular tools has led to improved diagnosis and has also led to an increase in known host species. Here we report a putative intranuclear coccidium in Mauremys leprosa (Schweigger), from Morocco, based on 18S rDNA sequence analysis. This is, to the best of our knowledge, the first report of this parasite from a freshwater terrapin species.