Helminth Species and Infracommunities in Frogs Pelophylax ridibundus and P. esculentus (Amphibia: Ranidae) in Northern Ukraine.

PURPOSE: The study aims to characterise and compare the helminth assemblages and helminth infracommunities in the marsh frog, Pelophylax ridibundus and the edible frog, P. esculentus collected in the northern part of Ukraine. METHODS: Occurrence and abundance of the helminths were analysed by calculating the prevalence, intensity, and mean abundance of infection; similarities between the infracommunities were estimated by the Bray-Curtis index and visualised using nMDS plots. Dissimilarities were estimated using the ANOSIM and SIMPER routines. RESULTS: In total, 27 helminth species were found in 143 frogs. Pelophylax ridibundus (n = 86) harboured 20 species of helminths, 24 species were found in P. esculentus (n = 57), and 17 species were shared by the two hosts. Oswaldocruzia bialata and larval Strigea sp. were absent in P. ridibundus, while they reached the prevalence of 30% and 10%, respectively, in P. esculentus. Cosmocerca ornata, Diplodiscus subclavatus, Opisthioglyphe ranae, and Codonocephalus urniger had significantly larger prevalence in P. ridibundus, whereas Haematoloechus asper was found to be more prevalent in P. esculentus. Acanthocephalus ranae, Icosiella neglecta, Haematoloechus variegatus, Pleurogenes claviger, Pleurogenoides medians, and Prosotocus confusus were equally common in both hosts. Helminth infracommunities in the two hosts had identical species richness (1-10 species, 4 on average); abundance was significantly higher in P. ridibundus. CONCLUSIONS: Helminth assemblages of the two hosts in northern Ukraine are rather similar; however, small but significant differences were found in their species composition, parameters of infection in some species, and structure of helminth infracommunities.

Morphological and ultrastructural characteristics of Myxobolus ridibundae n. sp. (Myxosporea: Bivalvulida) infecting the testicular tissue of the marsh frog Rana ridibunda (Amphibia: Ranidae) in Egypt.

Myxozoans are one of the most economically important groups of protozoan parasites causing many serious diseases of their hosts. In the present study, a total of 60 live adult male specimens of the marsh frog Rana ridibunda have been randomly captured during the period of January-December 2015 in different areas at Kafr El-Sheikh Governorate, Egypt and were examined for infection by myxosporidian parasites. A total of 48 (80.0 %) out of 60 frog specimens were found to be infected with Myxobolus species. Parasitic infection was restricted to the testicular tissue of the examined frogs. Macroscopic cysts (plasmodia) which heavily infested different parts of the testes were recovered. Morphological and ultrastructural characteristics of these myxosporidian species were carried out using light and transmission electron microscopy. Plasmodia measured 0.16-0.53 (0.34 ± 0.01) mm in diameter. Mature spores appeared oval in frontal view, measuring 8.9-11.5 (9.6 ± 0.1) µm in length and 7.5-9.1 (8.4 ± 0.1) µm in width containing 5-6 turns of polar filaments. Morphometric characterization revealed that the very small size of the present Myxobolus species was the most distinctive feature that separates them from all previously described Myxobolus species. Ultrastructural analysis showed that the plasmodia are surrounded by a plasma membrane with numerous pinocytotic protrusions extending toward the host cell. The generative cells and the different developmental stages are arranged at the periphery of the plasmodia, while immature and mature spores are centrally located. Sporogenesis, capsulogenesis, valvogenesis, and spore maturation of the present parasite are also described. The present species is described as Myxobolus ridibundae and represents a new species.

A metazoan parasitological research of some Iraqi amphibians.

The incidence and intensity of metazoan parasites in 3 species of Iraqi amphibians were studied. The amphibians were Rana ridibunda, Bufo viridis and Hyla arborea. Twenty-four species of helminths were encountered, including 16 trematodes, 1 cestode and 7 nematodes. Their respective names are: Polystoma integerrimum, Prosotocus confusus, P. fuelleborni, Pleurogenoides gastroporus, P. medians, Sonsinotrema tacapense, Opisthioglyphe ranae, Haplometra cylindracea, Haematoloechus volgensis, H. vitelloconfluentum, H. similis, H. asper, Gorgoderina vitelliloba, Gorgodera euzeti, G. amplicava, Nematotaenia dispar, Cosmocerca ornata, C. commutata, Aplectana acuminata, Aplectana sp., Oxysomatium sp., Ozwaldocruzia filiformis and Rhabdias bufonis. Collection localities, infection sites and rates and parasite burdens were determined throughout the species list. The highest and lowest rates of infection were for R. bufonis in B. viridis and O. ranae in R. ridibunda, while the highest and lowest worm burdens were for C. ornata in R. ridibunda and P. integerrimum in B. viridis. Seven of the species included in this study are thought to be new for Iraq.

An investigation on endoparasites of Rana ridibunda complex (s. l.) with dermal parasite (metacercariae) in Dalaman (Turkey).

In this study, endoparasites of the Rana ridibunda specimens collected from Dalaman area, southwestern Turkey were investigated. In the intestine of 17 specimens of R. ridibunda, five different parasites, represented by three species of the trematoda (Diplodiscus sp, Pleurogenoides sp, Plagiorchis sp) and two genera of round worms (Cosmocerca sp; Foleyella sp) were recognized. The trematoda and one of the round worms were found in the rectal region whereas the other round worm species are observed in the abdominal cavity.

Endohelminth fauna of the marsh frog Rana ridibunda from Lake Hazar, Turkey.

In this study, 236 marsh frogs Rana ridibunda collected from Lake Hazar (Elazig, Turkey) at 15 d intervals between March 2001 and February 2002 were examined for endohelminths; of these, 148 (62.71%) frogs were found to be infected with helminths. In total, 9 helminth species (3 trematodes, 5 nematodes and 1 acanthocephalan) were identified. We observed Gorgoderina vitelliloba (prevalence 2.97%) in the urinary bladder, Haematoloechus variegatus (4.66%) and Rhabdias bufonis (8.90%) in the lung, Pleurogenoides medians (1.69%), Oswaldocruzia filiformis (3.81 %) and Acanthocephalus ranae (26.27 %) in the small intestine, Neoxysomatium brevicaudatum (16.95%) and Cosmocercoides sp. (3.39%) in the large intestine, and Eustrongylides excisus (14.41%) in the body cavity and on,the stomach. No helminth was found in the spleen, kidney, gall bladder, liver, heart or muscle. Of the 9 helminth species identified, Acanthocephalus ranae (26.27 %) had the highest prevalence and abundance and Oswaldocruzia filiformis (8.33+/-4.09) had the highest mean intensity.

[Helminths of amphibians of the Fergana valley of Uzbekistan]. / Gel'minty amfibii Ferganskoi doliny Uzbekistana.

Species diversity and some ecological peculiarities of helminthes parasitizing amphibians in the Fergana Valley of Uzbekistan have been investigated. In 652 examined specimens of amphibians (Bufo viridis--237, Rana ridibunda--415 specimens), have been found 32 helminth species belonging to 26 genera of 12 families.

Erythrocytic and merogonic stages of Hepatozoon ridibundae sp. nov. infecting the Arabian ranid frogs, Rana ridibunda in Saudi Arabia with reflections on the haemogregarine complex.

The prevalence and levels of parasitaemia of haemogregarine infection among Arabian ranid frogs, Rana ridibunda, in Saudi Arabia was studied for the first time. Erythrocytic and merogonic stages of Hepatozoon ridibundae sp. nov. in the intermediate vertebrate host, R. ridibunda were described by light microscopy. The erythrocytic parasites were differentiated into small form (trophozoite) measuring 14.6 +/- 0.3 x 3.8 +/- 0.4 microm and the mature form (gamont) which was banana-shaped with hooked anterior end and blunt broad posterior end and measuring 19.8 +/- 1.8 x 5.2 +/- 0.6 microm. The gamonts of the present parasite induced nuclear fragmentation or segmentation in host erythrocytes. Merogony, of the ectomerogonic type, took place in the liver parenchyma cells. Two meront types were observed. Small meronts (micromeronts) yielded 2-6 (average 4) large merozoites (macromerozoites) measuring 16.6 +/- 0.6 x 6.2 +/- 0.5 microm in size. Large meronts (macromeronts) yielded 18-30 (average 24) elongated merozoites (micromerozoites) measuring 15.2 +/- 0.3 x 3.8 +/- 0.4 microm. A partial systematic revision of the haemogregarine complex was discussed in the view of the diagnostic characteristic features of the 6 recognized haemogregarine genera.

Redescription of Goussia neglecta n. comb. (Nöller, 1920) (Apicomplexa; Coccidia) and notes on its occurrence in the gut of tadpoles.

Coccidian infection in Rana ridibunda and R. esculenta tadpoles was recorded in Hungarian fish farms. Oocysts enclosed in yellow bodies were found in the faeces and in the intestinal epithelium. Developmental stages also had intraepithelial sites. The species was identified with Eimeria neglecta Nöller, 1920; however, on the basis of its oocyst morphology it was transferred to the genus Goussia. Besides stages of Goussia neglecta n. comb., intranuclear trophozoites of another coccidian species were also recorded.

[Tegumental ultrastructure of Opisthioglyphe ranae (Trematoda, Plagiorchidae)]. / Ul'trastruktura tegumenta Opisthioglyphe ranae (Trematoda, Plagiorchidae).

Tegument ultrastructure of O. ranae from the gut of Rana ridibunda has been studied. It has general features of the tegument of other trematodes.