Some digenetic trematodes found in a loggerhead sea turtle (Caretta caretta) from Brazil

Summary This paper reports three recovered species of digeneans from an adult loggerhead sea turtle - Caretta caretta (Testudines, Cheloniidae) in Brazil. These trematodes include Diaschistorchis pandus (Pronocephalidae), Cymatocarpus solearis (Brachycoeliidae) and Rhytidodes gelatinosus (Rhytidodidae) The first two represent new geographic records. A list of helminths reported from the Neotropical region, Gulf of Mexico and USA (Florida) is presented.

Helminth eggs from early cretaceous faeces

The exceptional fossil site of Las Hoyas (upper Barremian, Cuenca, Spain) yields abundant small to medium vertebrate coprolites, hindering the search for parasites. We studied the contents of 29 coprolites that were previously classified into distinct morphotypes. Several parasitic eggs were retrieved from two of these coprolites, confirming the second record of digenea trematode eggs and nematode (ascaridid) eggs from an Early Cretaceous locality. The cylindrical coprolite containing anisakid eggs was likely produced by a crocodylomorph as the parasite host, whereas the bump-headed lace coprolite indicates the role of a fish as an intermediary or definitive host of the trematodes and ascaridids. These trace and body fossils show that the Las Hoyas 126–129 Ma lacustrine ecosystem documents the early connection between basal Gonorynchiformes fish and digenetic trematodes.

Digenetic trematodes infecting anurans from a derived savanna biotope in Edo State, Nigeria

An investigation of the digenetic trematodes of anurans from Agbede, a location in the derived savanna biotope in Edo state,Nigeria was conducted from August, 2007 to July, 2008. Anuran hosts examined included Sclerophrys maculata, S.regularis, Ptychadena pumilio, P. bibroni, P. oxyrhynchus, Hoplobatrachus occipitalis and Hylarana galamensis. Theanurans were collected using the Visual Acoustic Encounter Survey (VAES) method, dissected and examined for trematodeinfections. A total of 267 anurans were examined of which 33 were infected with an overall prevalence of 12.36%. Seasonalprevalence was 14.88% for the wet season and 8.08% for dry season. The difference in prevalence values was not statisticallysignificant (p >0.05). Four digenetic trematodes, namely, Mesocoelium monodi, an unidentified Mesocoelium sp.,Haematoloechus exoterorchis and an unidentified Haematoloechus sp. Haematoloechus exoterorchis was recovered from H.occipitalis while the unidentified Haematoloechus sp. infected H. occipitalis and Sclerophrys maculata. Mesocoeliummonodi infected only Sclerophrys maculata while the unidentified Mesocoelium sp. was a generalist, infecting five anuranhosts. Sclerophrys maculata is thus a new host record for the genus Haematoloechus in Nigeria. In conclusion, this studyrevealed a low trematode diversity in the anurans of the savanna-mosaic at Agbede. However, anurans from this locationharboured two new trematodes: an unidentified Mesocoelium sp and a Haematolechus sp. Sclerophrys maculata as a newhost record for the genus Haematoloechus in Nigeria. More specimens of the Haematoloechus sp. are needed for themorphological description and molecular characterization of the parasite, to establish its relationship with the cogener inH.occipitalis. Keywords: Derived savannah, Anurans, Digenetic trematodes, new host record

Helminth parasitic infections of leaf litter frogs (Arthroleptis and Phrynobatrachus spp.) from cocoa plantations in southern Nigeria

The endohelminths parasitizing leaf litter frogs (LLFs) at Ojo Camp, Ugboke, Ovia South West Local Government Area of Edo State, Nigeria were investigated. The frogs were collected from cocoa plantations (CPs) exposed to pesticides and from the village settlement (VS) located outside the pesticide use environment, for 15 months, using the Visual Acoustic Encounter Surveys method and disturbance searches. Two genera of LLFs were encountered: Arthroleptis (A. poecilonotus, A. variabilis, and six other undetermined Arthroleptis spp.) and Phrynobatrachus (P. auritus, P. plicatus, P. natalensis and Phrynobatrachus sp.). The overall prevalence of infection in LLFs from the CPs and VS were 37.4% and 50.0%, respectively but thedifference was not significant (p>0.05). The most parasitized LLF in the CPs was the unidentified Phrynobatrachus sp. (64.7%); in the VS infections were only recorded in A. poecilonotus (50%, n=4) and the single specimens of Arthroleptis sp. 2 collected from this habitat. The helminth parasites recovered included four cestodes (two adults: Cylindrotaenia jaegerskioeldi and Ophiotaenia sp.) and two larvae (two unidentified Proteocephalus spp.), three digenetic trematodes (two unidentified Mesocoelium spp. and a strigeoid larva) and eight nematode species (Amplicaecum sp., Aplectana sp., Cosmocerca ornata, Cosmocerca sp., Foleyellides sp., Physaloptera sp., Rhabdias sp. and an Ascaridida sp.). Although the cocoa plantations had very high species richness and diversity of parasites (15 parasite species), the intensity of infection was low. This generally low infection intensity reflects the inhibitory effects of the pesticide-contaminated environment of the CPs on parasite larval development and transmission. Keywords: Leaf litter frogs; helminth parasites; prevalence; intensity; cocoa plantations; pesticides.

Infections of Digenetic Trematode Metacercariae in Wrestling Halfbeak, Dermogenys pusilla from Bangkok Metropolitan Region in Thailand

This study aimed to investigate metacercarial infections in the wrestling halfbeak, <i>Dermogenys pusilla</i>, collected from Bangkok metropolitan region of Thailand. A total of 4,501 fish from 78 study sites were commonly examined with muscle compression and digestion methods (only head part of fish) during September 2017 to July 2018. The overall prevalence of metacercarial infection was 86.1% (3,876/4,501 individuals), and the mean intensity was 48.9 metacercariae per fish infected. Four species, i.e., <i>Posthodiplostomum</i> sp., <i>Stellantchasmus falcatus</i>, Cyathocotylidae fam. sp., and <i>Centrocestus formosanus</i>, of digenetic trematode metacercariae (DTM) were detected. The prevalences were 65.8%, 52.0%, 2.1%, and 1.2%, respectively and their mean intensities were 23.1, 51.6, 1.4, and 3.2 per fish infected, respectively. The seasonal prevalences were 81.0% in winter, 87.8% in summer and 87.4% in rainy, and the mean intensities were 38.9, 46.6, and 55.2 metacercariae per fish infected, respectively. Conclusively, it was confirmed that the wrestling halfbeak play the role of second intermediate hosts of 4 species of digenetic trematodes including <i>S. falcatus</i> and <i>Posthodiplostomum</i> sp. in Bangkok metropolitan region. And then the metacercariae of <i>C. formosanus</i> and Cyathocotylidae fam. sp. are to be first found in the wrestling halfbeak by this study.

Phylogenetic position of Pleurogenoides species (Plagiorchiida: Pleurogenidae) from the duodenum of Indian skipper frog, Euphlyctis cyanophlyctis (Amphibia: Dicroglossidae) inhabiting the Western Ghats, India

SummaryTwo species of digenetic trematodes of the genus Pleurogenoides viz., P. cyanophlyctiShinad & Prasadan (2018a) and P. euphlyctiShinad & Prasadan (2018b) have been described from India. Information regarding the molecular data of various species of the genus Pleurogenoides Travassos, 1921 is virtually lacking. This study addresses the application of molecular markers to validate the phylogenetic position of P. cyanophlycti and P. euphlycti. In the present study, two species P. cyanophlycti and P. euphlycti were collected between January 2016 to October 2017, infecting the freshwater frogs inhabiting the Western Ghats, India. In the present study, the two species were identifi ed morphologically and by PCR amplification of the 28S ribosomal RNA gene. Phylogenetic tree results clearly demonstrate that both P. cyanophlycti and P. euphlycti belongs to the family Pleurogenidae Looss, 1899. Based on these results, we presented and discussed the phylogenetic relationships of P. cyanophlycti and P. euphlycti within family Pleurogenidae from India. Phylogenetic analyses showed that P. cyanophlycti and P. euphlycti cluster according to their vertebrate host and revealed an important congruence between the phylogenetic trees of Pleurogenoides and of their vertebrate hosts. P. cyanophlycti and P. euphlycti clearly constitute a separate, sister branch with other species of the genera, Pleurogenoides, Pleurogenes (=Candidotrema), Prosotocus and Brandesia. The present study firstly provides important information about the molecular study and phylogenetic analysis of P. cyanophlycti and P. euphlycti. This study will also serve as a baseline for Pleurogenoides species identifi cation for further studies.