Cosmocerca goroensis n. sp. (Nematoda: Cosmocercidae) from South Africa and its phylogenetic relationships with other cosmocercids based on partial 28S sequences.

Nematodes of the genus Cosmocerca are commonly found in various amphibians in South Africa and in most cases are identified as C. ornata. However, after detailed morphological studies and molecular approaches, three new species of the genus were recently described from three different frogs in South Africa. In present study, we describe another new species - Cosmocerca goroensis parasitising the Northern Pygmy Toad Poyntonophrynus fenoulheti in Soutpansberg mountains, Limpopo province, South Africa. The new species is characterised by prominent sex dimorphism, wide lateral alae, numerous somatic papillae in both sexes, and wide triangularly shaped gubernaculum and simple prominent spicules in males. Cosmocerca goroensis n. sp. distinguished from congeners, previously reported in Southern Africa by the shape of the gubernaculum and arrangement of somatic papillae in males. Morphological differences were confirmed by molecular analysis based on fragments of the 28S gene. Phylogenetic analysis based on the 28S gene fragments, including C. goroensis n. sp. and newly obtained sequence of C. ornata from Pelophylax lessonae from Ukraine, supported previously known data of closer relationships between species of Cosmocerca and Aplectana and more distant with Cosmocercoides spp.

Infection patterns of helminth community in black rockcod Notothenia coriiceps in West Antarctica over a 6-year term.

Patterns of the rockcod Notothenia coriiceps infection with helminths were analysed to understand the dynamics of parasite communities in this Antarctic fish and to test their stability over time. The study was performed using helminth samples collected from 183 N. coriiceps in 2014-2015 and 2020-2021 in the vicinity of the Ukrainian Antarctic station (UAS) "Akademik Vernadsky", Galindez Island, Argentine Islands, West Antarctica. Overall, 25 helminth taxonomical categories (nine trematodes, four cestodes, five nematodes, and seven acanthocephalans) were subjected to analysis. A direct comparison of the helminth population characteristics showed that nine species significantly changed their infection parameters during the 6 years between the samples. Seven of them (Pseudoterranova sp., Contracaecum sp., Ascarophis nototheniae, monolocular metacestodes, bilocular metacestodes, Metacanthocephalus rennicki, and Diphyllobothrium sp.) were found to have a significant impact on the differences between helminth infracommunities in 2014-2015 and 2020-2021. Most studied patterns of helminth component community appeared to show a stable tendency, and observed fluctuations were close to the steady trend. Slight but significant changes in the infection patterns observed in this study might have been caused by changes in the populations of intermediate, paratenic, and definitive hosts of helminths (marine invertebrates, mammals, and birds), which participate in helminth transmission in Antarctic ecosystems.

Three new species of Rhabdias Stiles et Hassall, 1905 (Nematoda: Rhabdiasidae) parasitic in Ptychadena spp. (Amphibia: Anura: Ptychadenidae) and an identification key to Rhabdias spp. from Afrotropical anurans.

Three new species of lung-dwelling nematodes are described from the frogs Ptychadena anchietae (Bocage), P. oxyrhynchus (Smith), and P. uzungwensis (Loveridge) in southern Africa. All three species are medium-sized species of Rhabdias Stiles et Hassall, 1905, with the thick-walled buccal capsules measuring 11-13 µm × 6-11 µm, consisting of longer anterior and shorter posterior parts. Rhabdias athos n. sp. and R. porthos n. sp. are characterised by the rounded anterior end of the body and the presence of short dilatation of the oesophagus at its mid-length. Rhabdias porthos n. sp. has distinct excretory glands which are absent in two other species. Rhabdias aramis n. sp. is characterised by the truncated anterior end and the slight constriction of the oesophagus at the level of its mid-length. Phylogenetic analysis based on ITS-28S rDNA sequences placed R. aramis n. sp. in the clade consisting of R. engelbrechti Kuzmin et al., 2017 from South Africa and Eurasian Rhabdias spp., while R. athos n. sp. and R. porthos n. sp. formed a sister group to that clade. Identification key to 14 Rhabdias spp. parasitic in anuran amphibians from the Afrotropical Realm is provided.

Helminth Assemblages of the Antarctic Black Rockcod, Notothenia coriiceps (Actinopterygii: Nototheniidae) in Coastal Waters near Galindez Island (Argentine Islands, West Antarctic): Temporal Changes in the Endoparasite Community.

PURPOSE: Analysis and comparison of the helminth assemblages in Antarctic rockcod Notothenia coriiceps collected near the UAS "Akademik Vernadsky" (Argentine Islands, West Antarctica) in 2002 and 2014-2015 were performed to characterise the parasite community and investigate the temporal changes in helminth assemblages and infection parameters. METHODS: All specimens of N. coriiceps (n = 194) were caught at depths of 10-30 m. Parasites (22,856 helminth specimens and 15,057 cysts) were collected manually and identified based on their morphology. Statistical analysis of the quantitative data was performed using the Quantitative Parasitology 3.0 (QP 3.0), Paleontological Statistics (PAST v. 3.1), and PRIMER 6 software. RESULTS: Twenty-seven species of four taxonomic groups were recorded: trematodes (8 species), cestodes (4), nematodes (5), and acanthocephalans (10). Helminth samples collected in 2002 and 2014-2015 showed a rather high similarity in species composition. The species richness was higher in the sample collected in 2014-2015, while the evenness and diversity in the two samples were similar. The dissimilarity between helminth infracommunities in the two samples appeared to be statistically significant. Larval cestodes Diphyllobotrium sp., the acanthocephalan Metacanthocephalus rennicki, and the trematode Neoleoburia antarctica were found to make the most significant impact on the dissimilarity. CONCLUSIONS: The analysis of the composition and structure of helminth community in N. coriiceps revealed the changes that have happened during the last decade. At least some of the changes are attributed to the changes in marine ecosystems in Western Antarctica.

A new species of Serpentirhabdias Tkach, Kuzmin et Snyder, 2014 (Nematoda: Rhabdiasidae) parasitic in the herald snake, Crotaphopeltis hotamboeia (Laurenti) (Reptilia: Serpentes: Colubridae) in South Africa.

Serpentirhabdias mamlambo n. sp. is described from the lung of the herald snake, Crotaphopeltis hotamboeia (Laurenti) in KwaZulu-Natal Province, South Africa. The new species is characterised by the small lips, the absence of the buccal capsule, the large excretory glands (1.5-2.3 times longer than the oesophagus), and the numerous eggs in uteri. Serpentirhabdias mamlambo n. sp. differs from other Serpentirhabdias spp. in the presence of M-shaped cuticular folds on dorsal and ventral sides of apical surface, the eye-shaped internal labial papillae, and the distinct dilatation of the oesophagus at its mid-length. Morphological differentiation of S. mamlambo n. sp. from its congeners is supported by molecular evidence based on cox1 mitochondrial gene, and ITS and partial 28S region of nuclear rDNA. Serpentirhabdias mamlambo n. sp. is the first species of the genus Serpentirhabdias described from the Afrotropical Realm.

Helminths of the Antarctic dragonfish, Parachaenichthys charcoti (Perciformes, Notothenioidei, Bathydraconidae) Studied near Galindez Island (Argentine Islands, West Antarctica).

PURPOSE: The Antarctic dragonfish, Parachaenichthys charcoti is a notothenioid teleost fish endemic to the Southern Ocean surrounding Antarctica. It is a relatively rare fish species; therefore, published data on the parasite communities of P. charcoti are limited. The present study was performed on the Ukrainian Antarctic Station "Akademik Vernadsky", Argentine Islands, West Antarctica and the purpose was to examine the species diversity of the parasites of P. charcoti and to identify the parameters of helminth infection and helminth component community. METHODS: Fifteen specimens of P. charcoti were caught at a depth of 10-30 m and examined using standard parasitological techniques. All helminths (6251 specimens) were collected manually, fixed in 70% ethanol and identified based on their morphology. RESULTS: All examined specimens of P. charcoti were found to be infected with helminths; each fish harboured 10-20 helminth species (mean 13.2; median 13) and 237-804 helminth specimens (mean 417; median 401). Twenty-seven helminth species were found, including nine species of trematodes, 4 of cestodes, 4 of nematodes and 10 of acanthocephalans. P. charcoti is the definitive host for 11 out of 27 helminth species recorded. In the helminth component community, the diversity indices were 2.03 (Shannon's index) and 0.79 (Simpson's index); Pielou evenness index was 0.61, and Berger-Parker dominance index was 0.38. CONCLUSIONS: Our results indicate a high species diversity and complex structure of the helminth community in Antarctic dragonfish P. charcoti in the Argentine Islands.

Two new species of Neofoleyellides (Nematoda: Onchocercidae) parasitising anuran amphibians in South Africa.

The genus Neofoleyellides was recently erected for a single species, Neofoleyellides boerewors from bufonid hosts in South Africa. In present study, we discovered two undescribed species of Neofoleyellides, namely N. steyni n. sp. and N. martini n. sp. parasitising frogs Amietia delalandii and Leptopelis natalensis, respectively. Both species differ from N. boerewors and between each other in shape and relative length of oesophagus, size of spicules, arrangement of genital papillae and morphology of caudal alae in males. Phylogenetic analysis based on concatenated fragments of the 18S ribosomal ribonucleic acid (18S rRNA) and the Cytochrome oxidase c subunit I (COI) genes confirmed both species as Neofoleyellides sister to Icosiellinae and Oswaldofilariinae.

Review of metazoan parasites of the northern fur seal (Callorhinus ursinus) and the analysis of the gastrointestinal helminth community of the population on St. Paul Island, Alaska.

The northern fur seal (NFS), Callorhinus ursinus (Mammalia: Otariidae), is a marine mammal species included into the IUCN Red List as the vulnerable species which population is dramatically declining. A significant amount of parasitological data collected previously and our recent data allowed us to clarify the list of NFS metazoan parasites and to perform a comprehensive analysis of the gastrointestinal helminth community. Gastrointestinal tracts from 756 NFSs (3- to 4-year-old males) were collected during the annual Aleut subsistence harvests in July-August of 2011-2014 from five separate rookeries on St. Paul Island, Alaska. Totally, 27,625 specimens of helminths and approximately 1000 nasal mites were collected and identified. Detailed analysis of the previously published and newly obtained data revealed 32 species of metazoan parasites, including trematodes (6 species), cestodes (4), nematodes (9), acanthocephalans (9) and arthropods (4). The gastrointestinal helminth community of newly studied NFSs comprised 19 species including trematodes (4), cestodes (3), nematodes (5) and acanthocephalans (7). Temporal changes in the helminth community structure were small but statistically significant. Gastrointestinal helminth infracommunities comprised from 1 to 10 species (average of 4). Small but significant correlation was found between the abundances of acanthocephalans (Corynosoma similis and C. strumosum), nematodes (Contracaecum osculatum, Pseudoterranova spp.) and cestode Diphyllobothrium tetrapterum.

New records of Amphibiophilus spp. (Nematoda: Amphibiophilidae) parasitic in Strongylopus grayii (Smith) and Amietia delalandii (Duméril & Bibron) (Amphibia: Anura: Pyxicephalidae) in South Africa, with a description of Amphibiophilus bialatus n. sp.

Nematodes of the genus Amphibiophilus Skrjabin, 1916 are a small group of parasites restricted to pyxicephalid frogs in southern Africa. In the present study, the new species A. bialatus parasitising the clicking stream frog Strongylopus grayii (Smith) as well as two forms parasitising the common river frog Amietia delalandii (Duméril & Bibron) from two distant localities are described. Amphibiophilus bialatus n. sp. clearly differs from the remaining species of the genus by having wide cervical alae, the dorsal oesophageal tooth not reaching the oral opening, and the presence of extra processes on the spicules. Specimens parasitising Am. delalandii in Mpumalanga Province and Limpopo Province, South Africa, differed from other species and from each other in the shape of the gubernaculum, though were almost identical in other characters. Based on morphological and molecular data, specimens from two localities were assigned to Amphibiophilus sp. 1 and Amphibiophilus sp. 2. Pairwise analyses of ITS-28S and cox1 gene fragments are presented for four Amphibiophilus spp.

Description and molecular characterisation of a new nematode species parasitic in the lungs of Strongylopus grayii (Smith) (Anura: Pyxicephalidae) in South Africa.

Rhabdias delangei n. sp. (Nematoda: Rhabdiasidae) is described from the lungs of the clicking stream frog Strongylopus grayii (Smith) in the Western Cape Province of South Africa. The new species is characterised by the nerve-ring being located just posterior to the mid-length of the oesophagus, a pre-equatorial vulva, as well as a thin-walled and apparently underdeveloped rectum. Pairwise analyses based on ITS-28S and partial cox1 gene fragments showed significant differences between R. delangei n. sp. and its congeners from the Afrotropical Realm. Rhabdias delangei n. sp. is the 12th species of Rhabdias Stiles & Hassall, 1905 recorded in Afrotropical amphibians and the second species of the genus found in pyxicephalid hosts. Our phylogenetic analysis based on the ITS-28S region showed that the new species is closely related to the European species R. rubrovenosa (Schneider, 1866). Furthermore, both species are similar with respect to the underdeveloped rectum and pre-equatorial position of vulva.

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.

Phylogenetic Position of Codonocephalus Diesing, 1850 (Digenea, Diplostomoidea), an Unusual Diplostomid with Progenetic Metacercariae.

Codonocephalus is a monotypic genus of diplostomid digeneans and is the only genus in the sub-family Codonocephalinae. The type-species Codonocephalus urniger has an unusual progenetic metacercaria that uses frogs as intermediate hosts and can use snakes as paratenic hosts. Adult C. urniger parasitize ardeid wading birds in the Palearctic. Despite the broad distribution of Codonocephalus, no DNA sequence data are currently available for the genus. In this study, we generated sequence data for nuclear ribosomal and mitochondrial DNA from progenetic metacercaria of the type-species C. urniger from marsh frog, Pelophylax ridibundus, collected in Ukraine. We used partial sequences of the nuclear ribosomal 28S gene to examine for the first time the phylogenetic position of Codonocephalus among the Diplostomoidea.

Description, biology and molecular characterisation of Serpentirhabdias moi n. sp. (Nematoda: Rhabdiasidae) from Chironius exoletus (Serpentes: Colubridae) in Brazil.

A new species of the genus Serpentirhabdias Tkach, Kuzmin et Snyder, 2014, S. moi n. sp., is described from a colubroid snake Chironius exoletus from Caxiuanã National Forest, State of Pará, Brazil. The species is characterised by having a triangular oral opening, absence of the buccal capsule, presence of six minute onchia in the oesophastome, and excretory glands of approximately the same length as the oesophagus. These qualitative morphological characters, as well as some measurements, differentiate the new species from other Neotropical and Nearctic Serpentirhabdias spp. The morphological description of parasitic adults of S. moi n. sp. is complemented by the description of free-living stages including males, females, and infective larvae. Comparative analysis of partial sequences of cox1 and 12S mitochondrial genes strongly supported the status of S. moi n. sp. as a new species. Molecular phylogeny based on sequences of the nuclear DNA region spanning the 3' end of the 18S nuclear rRNA gene, ITS region (ITS1 + 5.8S + ITS2) and 5' end of the 28S gene supported monophyly of all rhabdiasid genera included in the analysis and placed the new species into the Serpentirhabdias clade as sister taxon to S. fuscovenosa.

Molecular and morphological characterisation of Rhabdias picardiae Junker, Lhermitte-Vallarino et Bain, 2010 (Nematoda: Rhabdiasidae) from Delaland's River Frog, Amietia delalandii (Duméril et Bibron, 1841) (Amphibia: Pyxicephalidae) in South Africa.

Rhabdias picardiae previously known from the Guttural Toad, Sclerophrys gutturalis (Bufonidae) is described from a new host, Delaland's River Frog, Amietia delalandii (Pyxicephalidae). The species identification is confirmed by analysis of the COI gene sequence and morphological comparison with the original description. Morphological details of apical structures in adult parasitic R. picardiae, namely, the shape and position of lips, the number and position of external labial papillae, and the buccal capsule morphology are described using light and scanning electron microscopy. The buccal capsule width and length, the distance from anterior end to nerve ring and excretory pore, and ratios of distance to vulva to body length and body length to width were identified as less variable metrical characters in the studied sample of 30 specimens. Adult specimens demonstrated differences in the position of lips in relation to the oral opening and position of the buccal capsule in relation to the oesophagus depending on the size (age) of worms. The infective larvae of R. picardiae are described for the first time and characterised by two lateral alae consisting of two ridges, triangular pseudolabia with rounded tops, and presence of ornamentation on the rounded tail tip.

Description and phylogenetic position of a new species of Rhabdias Stiles et Hassall, 1905 (Nematoda: Rhabdiasidae) from the banded rubber frog, Phrynomantis bifasciatus (Smith) (Amphibia: Microhylidae), in South Africa.

The lung-dwelling nematode Rhabdias engelbrechti sp. n. was found in five of eight examined banded rubber frogs in Limpopo Province, South Africa. The species is differentiated from species of Rhabdias Stiles et Hassall, 1905 occurring in the Afrotropical Realm based on the presence of a globular cuticular inflation at the anterior end, the buccal capsule walls being distinctly divided into anterior and posterior parts, the buccal capsule size (6-9 µm × 16-18 µm), and the body length (3.8-6.1 mm). Rhabdias engelbrechti is the tenth species of the genus found in Afrotropical anurans. Our molecular phylogenetic analysis based on the complete sequences of the ITS region and partial sequences of large subunit (28S) gene of the nuclear ribosomal RNA demonstrates that the new species is more closely related to the Eurasian species Rhabdias bufonis (Schrank, 1788) than to two other species from sub-Saharan Africa represented in the tree. In addition, partial sequences of the mitochondrial protein coding cox1 and ribosomal 12S genes of the new species have shown significant differences from all previously published sequences of these genes from African species of Rhabdias.

Two new species of Rhabdias Stiles et Hassall, 1905 (Nematoda: Rhabdiasidae) from anuran amphibians in Pará, Brazil.

Two new lung-dwelling nematode species of the genus Rhabdias Stiles et Hassall, 1905 were discovered in Caxiuanã National Forest, Pará state, Brazil. Rhabdias galactonoti sp. n. was found in a dendrobatid frog Adelphobates galactonotus (Steindachner). The species is characterised by the regularly folded inner surface of the anterior part of the buccal capsule seen in apical view, flask-shaped oesophageal bulb and narrow, elongated tail. Rhabdias stenocephala sp. n. from two species of leptodactylid frogs, Leptodactylus pentadactylus (Laurenti) (type host) and L. paraensis (Heyer), is characterised by a narrow anterior end that is separated from the remaining body by a constriction. Both species possess six small but distinct lips, a cuticle that is inflated along the whole body, a doliiform buccal capsule separated into a longer anterior and a shallow, ring-shaped posterior part, lateral pores in the body cuticle and zones of spermatogenesis in the syngonia. Rhabdias galactonoti sp. n. is the first species of the genus found in Dendrobatidae; R. stenocephala sp. n. is the second species described from Leptodactylidae in eastern Amazonia.

Description of Serpentirhabdias atroxi n. sp. (Nematoda: Rhabdiasidae), a parasite of Bothrops atrox (Linnaeus) (Reptilia: Serpentes: Viperidae) in Brazilian Amazonia.

A new lung-dwelling nematode species is described from the common lancehead Bothrops atrox (Linnaeus) in the Brazilian Amazon Region. The species is assigned to the genus Serpentirhabdias Tkach, Kuzmin & Snyder, 2014 based on the presence of six lips arranged in two lateral groups, the absence of prominent cuticular inflations, and lung parasitism in snakes. Serpentirhabdias atroxi n. sp. differs from other species of the genus mainly by details of the morphology of the anterior end: cuticularised ring surrounding the anterior part of the buccal cavity and six minute onchia present in the oesophastome. Serpentirhabdias atroxi n. sp. is the seventh species of the genus known from the Neotropical Realm and the second species described from viperid snakes.

The morphology of free-living stages and immature parasites of Rhabdias paraensis (Nematoda: Rhabdiasidae), a parasite of Rhinella marina (Anura: Bufonidae) in Brazil.

Rhabdias paraensis Santos, Melo, Nascimento, Nascimento, Giese et Furtado, 2011 was described based on fully gravid worms. Further investigations on the free-living stages, immature worms and young individuals were facilitated by cultivation in the laboratory, which allowed us to add new information about the morphology and development of the species. Observations on the free-living development of R. paraensis showed that the life cycle is typical of Rhabdias, with alternation of gonochoristic and hermaphroditic generations and without homogony. Males of the free-living generation were different from those in several species of the genus studied previously. In the original description, the excretory glands and duct were absent in gravid specimens of R. paraensis, while in this study, distinct excretory glands and a duct were observed in immature and young individuals. Additionally, we recognised the separation of the buccal capsule walls into anterior and posterior portions and described the specific shapes of these portions in lateral and apical view. Studies on the morphology and development of free-living stages of Rhabdias spp. from Neotropical regions may provide additional information for species determination.

Shaking the Tree: Multi-locus Sequence Typing Usurps Current Onchocercid (Filarial Nematode) Phylogeny.

During the past twenty years, a number of molecular analyses have been performed to determine the evolutionary relationships of Onchocercidae, a family of filarial nematodes encompassing several species of medical or veterinary importance. However, opportunities for broad taxonomic sampling have been scarce, and analyses were based mainly on 12S rDNA and coxI gene sequences. While being suitable for species differentiation, these mitochondrial genes cannot be used to infer phylogenetic hypotheses at higher taxonomic levels. In the present study, 48 species, representing seven of eight subfamilies within the Onchocercidae, were sampled and sequences of seven gene loci (nuclear and mitochondrial) analysed, resulting in the hitherto largest molecular phylogenetic investigation into this family. Although our data support the current hypothesis that the Oswaldofilariinae, Waltonellinae and Icosiellinae subfamilies separated early from the remaining onchocercids, Setariinae was recovered as a well separated clade. Dirofilaria, Loxodontofilaria and Onchocerca constituted a strongly supported clade despite belonging to different subfamilies (Onchocercinae and Dirofilariinae). Finally, the separation between Splendidofilariinae, Dirofilariinae and Onchocercinae will have to be reconsidered.

Some nematodes of the genus Rhabdias Stiles et Hassall, 1905 (Nematoda: Rhabdiasidae) parasitising amphibians in French Guiana.

Based on material collected from Rhinella cf. margaritifera (Laurenti) and Rhi. marina (Linnaeus) (Anura: Bufonidae) during a parasite survey of the herpetofauna of French Guiana, updated descriptions of Rhabdias androgyna Kloss, 1971 and R. fuelleborni Travassos, 1926 are presented. In addition to metrical data, which may overlap in closely related species, emphasis is placed on qualitative characters. Rhabdias androgyna is distinguished by the unique presence of an outer and inner cephalic cuticular inflation, a shoulder-like broadening of the body at the anterior end, a wide and shallow buccal capsule (average buccal ratio 0.36) with serrated lumen in apical view, a prominent anterior dilatation of the oesophagus, and the presence of an additional posterior dilatation anterior to the oesophageal bulb. Characters that may help to differentiate R. fuelleborni from closely related species parasitising the Rhi. marina species group are the presence of six relatively uniform lips, and the division of the buccal capsule into an anterior and posterior segment, with differently structured walls. Both the presence of R. androgyna and R. fuelleborni in French Guiana constitute new geographic records. A single specimen of Rhabdias sp. is described from Pristimantis chiastonotus (Lynch et Hoegmood) (Anura: Craugastoridae). This species differs from all its Neotropical congeners by the distinct globular swelling of its head, similar to that seen in only one Palaearctic and one Afrotropical Rhabdias species. A list of species of Rhabdias parasitising amphibians in the Netropical Realm is also provided.