Molecular phylogeny of the family Rhabdiasidae (Nematoda: Rhabditida), with morphology, genetic characterization and mitochondrial genomes of Rhabdias kafunata and R. bufonis.

BACKGROUND: The family Rhabdiasidae (Nematoda: Rhabditida) is a globally distributed group of nematode parasites, with over 110 species parasitic mainly in amphibians and reptiles. However, the systematic position of the family Rhabdiasidae in the order Rhabditida remains unsolved, and the evolutionary relationships among its genera are still unclear. Moreover, the present knowledge of the mitochondrial genomes of rhabdiasids remains limited. METHODS: Two rhabdiasid species: Rhabdias kafunata Sata, Takeuchi & Nakano, 2020 and R. bufonis (Schrank, 1788) collected from the Asiatic toad Bufo gargarizans Cantor (Amphibia: Anura) in China, were identified based on morphology (light and scanning electron microscopy) and molecular characterization (sequencing of the nuclear 28S and ITS regions and mitochondrial cox1 and 12S genes). The complete mitochondrial genomes of R. kafunata and R. bufonis were also sequenced and annotated for the first time. Moreover, phylogenetic analyses based on the amino acid sequences of 12 protein-coding genes (PCGs) of the mitochondrial genomes were performed to clarify the systematic position of the family Rhabdiasidae in the order Rhabditida using maximum likelihood (ML) and Bayesian inference (BI). The phylogenetic analyses based on the 28S + ITS sequences, were also inferred to assess the evolutionary relationships among the genera within Rhabdiasidae. RESULTS: The detailed morphology of the cephalic structures, vulva and eggs in R. kafunata and R. bufonis was revealed using scanning electron microscopy (SEM) for the first time. The characterization of 28S and ITS regions of R. kafunata was reported for the first time. The mitogenomes of R. kafunata and R. bufonis are 15,437 bp and 15,128 bp long, respectively, and both contain 36 genes, including 12 PCGs (missing atp8). Comparative mitogenomics revealed that the gene arrangement of R. kafunata and R. bufonis is different from all of the currently available mitogenomes of nematodes. Phylogenetic analyses based on the ITS + 28S data showed Neoentomelas and Kurilonema as sister lineages, and supported the monophyly of Entomelas, Pneumonema, Serpentirhabdias and Rhabdias. Mitochondrial phylogenomic results supported Rhabdiasidae as a member of the superfamily Rhabditoidea in the suborder Rhabditina, and its occurrance as sister to the family Rhabditidae. CONCLUSIONS: The complete mitochondrial genome of R. kafunata and R. bufonis were reported for the first time, and two new gene arrangements of mitogenomes in Nematoda were revealed. Mitogenomic phylogenetic results indicated that the family Rhabdiasidae is a member of Rhabditoidea in Rhabditina, and is closely related to Rhabditidae. Molecular phylogenies based on the ITS + 28S sequence data supported the validity of Kurilonema, and showed that Kurilonema is sister to Neoentomelas. The present phylogenetic results also indicated that the ancestors of rhabdiasids seem to have initially infected reptiles, then spreading to amphibians.

Pattern of anuran infection by acanthocephalans from the Cerrado, Northeastern Brazil with a summary for South America.

In Brazil, acanthocephalans parasitise anurans in several biomes. In the present study, we performed an analysis of acanthocephalan infections across 175 anuran individuals from the Cerrado biome, belonging to ten species: Boana raniceps, Pithecopus hypochondrialis, Scinax fuscomarginatus, Scinax x-signatus, Leptodactylus pustulatus, Leptodactylus macrosternum, Leptodactylus vastus, Physalaemus cuvieri, Adenomera hylaedactyla, and Elachistocleis piauiensis. We also verified the specificity of the parasites using the STD* index. Additionally, we conducted a survey of acanthocephalan infection in anurans in South America. The studied assemblage in the Brazilian Cerrado presented 57 parasitised hosts of 175 specimens (overall prevalence: 32.6%). In total, 437 acanthocephalans cystacanths were recorded, among which 286 presented the same morphotype but could not be identified, 148 belonged to the genus Centrorhynchus, and three belonged to Oncicola. Unidentified acanthocephalans had a higher prevalence in L. vastus (53.85%) and the highest intensity was in L. pustulatus (17±16). The highest prevalence of Centrorhynchus sp. was in the species S. fuscomarginatus (28.57%), while the highest intensity was observed in L. vastus (111). The taxon Oncicola sp. it had a prevalence of 3.23% and an intensity of 3 only in S. x-signatus. The highest specificity was recorded for Oncicola sp. (STD*= 1), whereas the lowest was found in Centrorhynchus sp. (STD*= 2.21). Finally, according to the survey for South America, we found ten records of acanthocephalan taxa parasitizing 58 species of anurans distributed in seven countries (Brazil with the most records).

A new species of Aplectana Railliet & Henry, 1916 (Nematoda: Cosmocercidae) in the Brazilian Amazon and the taxonomic status of Aplectana longa.

Nematodes of the genus Aplectana Railliet & Henry, 1916 are common parasites of the digestive tract of amphibians and reptiles in the Neotropical region. During a parasite survey on Boana boans (Linnaeus, 1758), we found specimens of nematodes with Aplectana characteristics. We observed a set of characteristics that differs the species of our study from its congeners, and the present study describes a new species of Aplectana parasite of B. boans using light microscopy and scanning electron microscopy. Aplectana pella n. sp. has lateral alae and somatic papillae in males and females; males have equal short spicules, and the gubernaculum is absent. The arrangement of pairs of caudal papillae also differs from other species (2 precloacal,1 adcloacal, and 5 postcloacal+1 unpaired). In females, the vulva is simple, with non-prominent lips, and equatorial. This is the first record of the genus Aplectana parasitizing B. boans and the 58th species described for this genus. Additionally, we added the precloacal papillae pattern of A. delirae, and based on morphological and morphometric characteristics, we propose the reallocation of Aplectana longa to the genus Oxyascaris.

Oswaldocruzia franciscoensis n. sp. (Nematoda: Molineidae) in Leptodactylus macrosternum Miranda-Ribeiro, 1926 (Anura: Leptodactylidae) from Caatinga morphoclimatic domain, Brazil: morphological and molecular characterisation.

A new species of Oswaldocruzia Travassos, 1917 (Nematoda, Molineidae), parasite of Leptodactylus macrosternum Miranda-Ribeiro, 1926 (Anura: Leptodactylidae), from Caatinga morphoclimatic domain, Brazil, is described based on morphological and molecular data. Oswaldocruzia franciscoensis n. sp. is characterised by an anterior extremity with a cephalic vesicle divided into two portions, a body covered by cuticular longitudinal ridges, and cervical alae. Males of the new species have caudal bursa of type I with a 2-1-2 pattern, spicules divided into a shoe, bifurcated fork, and blade with two unequal branches, in which the longer branch bifurcates at its distal portion end and the smaller branch with three distal processes, each with distal bifurcations. Females have didelphic and amphidelphic uteri, an ovijector divided into vestibule, anterior and posterior sphincters, and anterior and posterior infundibula. The new species differs from its Neotropical congeners that have caudal bursa of type I, based on the presence of cervical alae and by having a spicular blade distally divided into two unequal branches, with the longer branch bifurcating at its distal portion and smaller branch with three distal processes, each distally bifurcated. The partial 18S rDNA sequence generated for Oswaldocruzia franciscoensis n. sp. is the first of a representative belonging to this genus in the Neotropical region.

Putting infection on the map: Using heatmaps to characterise within- and between-host distributions of trematode metacercariae.

The location of parasites within individual hosts is often treated as a static trait, yet many parasite species can occur in multiple locations or organs within their hosts. Here, we apply distributional heat maps to study the within- and between-host infection patterns for four trematodes (Alaria marcianae, Cephalogonimus americanus, Echinostoma spp. and Ribeiroia ondatrae) within the amphibian hosts Pseudacris regilla and two species of Taricha. We developed heatmaps from 71 individual hosts from six locations in California, which illustrate stark differences among parasites both in their primary locations within amphibian hosts as well as their degree of location specificity. While metacercariae (i.e., cysts) of two parasites (C. americanus and A. marcianae) were relative generalists in habitat selection and often occurred throughout the host, two others (R. ondatrae and Echinostoma spp.) were highly localised to a specific organ or organ system. Comparing parasite distributions among these parasite taxa highlighted locations of overlap showing potential areas of interactions, such as the mandibular inner dermis region, chest and throat inner dermis and the tail reabsorption outer epidermis. Additionally, the within-host distribution of R. ondatrae differed between host species, with metacercariae aggregating in the anterior dermis areas of newts, compared with the posterior dermis area in frogs. The ability to measure fine-scale changes or alterations in parasite distributions has the potential to provide further insight about ecological questions concerning habitat preference, resource selection, host pathology and disease control.

Effect of altitude and spatial heterogeneity on the host-parasite relationship in anurans from a remnant humid forest in the brazilian semiarid.

In the present study, we investigated the effect of habitat heterogeneity, elevation gradient, and phylogenetic distance of host species on the abundance and richness of anuran endoparasites, assuming that parasites follow the distribution of their hosts independently of environmental variation. We collected 192 anurans distributed in three altitude ranges: 100-200 m, 400-500 m, and 700-800 m. We performed discriminant principal component analysis to analyze the interrelationships between environmental heterogeneity and the distribution of parasite and host species in the formation of species groups in each altitude range. We estimated the niche width and parasite overlap, using host species as a variable, and assessed whether parasite abundance is more influenced by historical (distance host phylogeny) or ecological effects in each altitude category and overall. Finally, we use network analyses to understand how interactions between parasites and hosts are formed along the altitude gradient. We found 22 parasite species, and the overall prevalence of infection was 74%. In our study, we did not identify environmental (altitude gradients and heterogeneity) or phylogenetic effects acting on the parasite species diversity. Overall, our results suggest that the parasites are distributed following the dispersal of their hosts and are dispersed among most anuran species.

A redescription of Hedruris moniezi Ibáñez & Córdova, 1976 (Nematoda: Hedruridae), an endoparasite of the Titicaca water frog Telmatobius culeus (Garman, 1876) (Anura: Telmatobiidae), with comments on all other known Hedruris species in Peru.

Hedruris moniezi Ibáñez & Córdova, 1976 (Nematoda: Hedruridae) was described using light and scanning electron microscopy (SEM) based on specimens collected from the stomach of Telmatobius culeus (Anura: Telmatobiidae) in Peru. We observed some characteristics not reported previously, including sessile and pedunculated papillae and amphid on the pseudolabia, bifid deirids, morphology of the retractable chitinous hook, morphology and arrangement of the plates on ventral surface of the posterior end of the males, and arrangement of caudal papillae. Telmatobius culeus represents a new host of H. moniezi. In addition, H. basilichtensis Mateo, 1971 is considered to be a junior synonym of H. oriestae Moniez, 1889. A key to valid species of Hedruris in Peru is provided.

Hematologic parameters and the effect of hemoparasites of wild anurans in Northern Sinaloa, Mexico.

BACKGROUND: Few hematologic profiles for free-ranging amphibians are available. Hematologic evaluation is a useful tool for determining the health of amphibian populations and providing further knowledge for conservation actions. OBJECTIVES: Hematologic variables and the presence and effect of hemoparasites in anuran species were evaluated in Northern Sinaloa, Mexico. METHODS: Blood samples were collected from wild anurans of eight species to perform blood cell counts, leukocyte differential counts, and serum protein concentrations using manual methods and refractometry. In addition, morphologic identification and quantification of the hemoparasites were performed on blood smears. RESULTS: Differences were observed by sex, age, and season for the hematologic values of Incilius alvarius (n = 23), Incilius mazatlanensis (n = 46), Rhinella horribilis (n = 64), Leptodactylus melanonotus (n = 46), Lithobates forreri (n = 135), Lithobates catesbeianus (n = 20), Smilisca fodiens (n = 42), and Scaphiopus couchii (n = 7). Intra- and extra-erythrocytic hemoparasites were found in 56.2% of amphibian hosts; the hemoparasite infection of R. horribilis and L. melanonotus was higher in the dry season, showing increases in erythroplastids and monocytes. For L. forreri, males were more infected than females, and increases in leukocytes were associated with infections of different types of hemoparasites species. CONCLUSIONS: Hematologic values, hemoparasite prevalence, and the response to hemoparasite infection vary among amphibian species, sex, and age, as well as on season and hemoparasite type. This highlights the importance of hematologic evaluations in wild amphibian populations to determine the subclinical effects of hemoparasite infections.

Top-down and bottom-up effects and relationships with local environmental factors in the water frog-helminth systems in Latvia.

Semi-aquatic European water frogs (Pelophylax spp.) harbour rich helminth infra-communities, whose effects on host population size in nature are poorly known. To study top-down and bottom-up effects, we conducted calling male water frog counts and parasitological investigations of helminths in waterbodies from different regions of Latvia, supplemented by descriptions of waterbody features and surrounding land use data. We performed a series of generalized linear model and zero-inflated negative binomial regressions to determine the best predictors for frog relative population size and helminth infra-communities. The highest-ranked (by Akaike information criterion correction, AICc) model explaining the water frog population size contained only waterbody variables, followed by the model containing only land use within 500 m, while the model containing helminth predictors had the lowest rank. Regarding helminth infection responses, the relative importance of the water frog population size varied from being non-significant (abundances of larval plagiorchiids and nematodes) to having a similar weight to waterbody features (abundances of larval diplostomids). In abundances of adult plagiorchiids and nematodes the best predictor was the host specimen size. Environmental factors had both direct effects from the habitat features (e.g., waterbody characteristics on frogs and diplostomids) and indirect effects through parasite-host interactions (impacts of anthropogenic habitats on frogs and helminths). Our study suggests the presence of synergy between top-down and bottom-up effects in the water frog-helminth system that creates a mutual dependence of frog and helminth population sizes and helps to balance helminth infections at a level that does not cause over-exploitation of the host resource.

Specific Diversity of Helminth Parasites of the Edible Frog Hoplobatrachus occipitalis (Günther, 1858) in Agricultural Landscapes in the South-East of Ivory Coast, Africa.

OBJECTIVE: This study describes the specific diversity of Helminth parasites of the edible frog Hoplobatrachus occipitalis (Günther, 1858) to assess the rate of infestation in three types of plantations (coconut, palm and banana plantations) in the south-east of Africa. METHODS AND RESULTS: A total of 156 frog specimens were collected in November 2019 from all the plantations and ten parasitic Helminth taxa were recorded. The overall prevalence (93.6%) showed a high infestation of the frog in these anthropized environments. The banana plantations that use the most fertilizers and pesticides had the highest prevalence (95.2%) suggesting pollution-related parasitic load. The number of parasites was higher in female frogs than in males, suggesting a sex-specific immune resistance. This study also highlights the parasite specificity and the sites of Helminth infestations. Trematodes of the genus Haematoelochus and Diplodiscus showed strict specificity in the lungs and large intestine/rectum of the host. The other parasites colonized the digestive tract with a more or less marked specificity. CONCLUSION: Our study provides several elements of response on the population of Helminth parasites of the edible frog Hoplobatrachus occipitalis, with a view to better knowledge, management, conservation and protection.

Metapolystoma ohlerianum n. sp. (Monogenea: Polystomatidae) from Aglyptodactylus madagascariensis (Anura: Mantellidae).

PURPOSE: Despite Madagascar's high amphibian diversity of more than 400 species, only a few polystome species are known from the island. The dissection of frogs from museum collections, together with amphibian and parasite surveys conducted in Madagascar led to the discovery of an undescribed polystome infecting Aglyptodactylus madagascariensis. The purpose of this study is to formally describe this species. METHODS: Polystomes recovered from A. madagascariensis were stained (Acetocarmine) and mounted (Canada balsam) to facilitate morphometrics and taxonomic drawings. Some specimens were fixed in absolute alcohol, a Bayesian tree inferred from the analysis of concatenated 18S, 28S and COI gene sequences was constructed and pairwise distances were calculated. Parasites collected from archived hosts in museums were used for histology and scanning electron microscopy (SEM). RESULTS: Polystomes recovered from A. madagascariensis display characteristics of the genus Metapolystoma and morphologically differed from all other known metapolystomes. The Bayesian phylogeny shows that Metapolystoma n. sp. ex. A. madagascariensis and M. falcatum are sister species with high Bayesian posterior probability. Histological and SEM investigations contributed to morphological descriptions. CONCLUSIONS: Morphological examination supported by phylogenetic analysis and genetic divergences revealed distinct differences from all known metapolystome species, supporting the description of a new species. Differences between the life cycles of Metapolystoma and Polystoma provided additional evidence for the validity of that genus as taxon. Whereas Polystoma may display ovoviviparity on rare occasions after incomplete egg expulsion towards the end of the breeding season, Metapolystoma displays true ovoviviparity. We emphasize the need for parasite surveys in Madagascar and recommended for museum material to be examined for polystomes to provide supplementary material and localities for further field investigation.

Hematologic variables of free-living Leptodactylus luctator with and without hemoparasites and thrombidiform mites in southern Brazil.

It has been suggested that anuran amphibian parasites can cause clinical signs in situations of environmental imbalance. In the family Leptodactylidae, information about hematology is scarce, although these are well-known tools for the diagnosis and prognosis in clinical practice and potential bioindicators of environmental stress. The objective of this study is to describe Leptodactylus luctator hematology, to report the occurrence of hemoparasites and thrombidiform mites, and to compare the hematological variables under the presence and absence of these organisms. Ectoparasites and heparinized blood samples from 40 free-living specimens of L. luctator were collected for analysis. Hematologic variables and total plasma protein were compared between groups with and without hemoparasites and intradermal mites. As results, structures compatible with hemogregarines, Lankesterella sp., five morphotypes of Trypanosoma spp., microfilaria, Aegyptianella sp., an unidentified intraleukocytic hemoparasite, and frog erythrocytic virus (FEV) inclusion bodies were identified in the blood samples, besides Hannemania spp. intradermal mites. The hemoparasite occurrence was higher than previously reported in other anuran families and locations. Also, L. luctator has smaller red blood cells (RBCs) and white blood cells (WBCs), and a hyposegmentation of the neutrophil nucleus, when compared to many other amphibians. White blood cell, neutrophil, and monocyte counts were higher in animals parasitized by mites. There was no correlation between the number of parasitized RBCs and hematologic variables. This study provides anuran hematologic information, in addition to indicating a host reaction to infestation by Hannemania spp. mites, besides constituting the first record of the distribution of hemoparasites and intradermal mites in L. luctator of the study region.

Morphological and molecular characterization of Cosmocercoides amapari n. sp. (Nematoda: Cosmocercidae), parasitic in hylid frogs from the Brazilian Amazon.

Cosmocercoides Wilkie, 1930 are gastrointestinal parasites commonly found in amphibians and reptiles, with 4 species reported from the Neotropical region. In the present study, a new species of Cosmocercoides, namely Cosmocercoides amapari n. sp. is described using integrated approaches such as light and scanning microscopy, and DNA sequencing of the mitochondrial cytochrome c oxidase subunit 1 gene. The specimens were collected from the large intestine of 3 species of hylid frogs in Amapá, Brazil. The new species can be distinguished from its congeners by morphological traits, including the pattern of caudal papillae, absence of the gubernaculum, 2 poorly sclerotized spicules, presence of lateral alae and somatic papillae along the body. In addition, our molecular analyses and phylogenetic reconstructions strongly support the status of the new taxon, which clustered poorly with a large clade of Cosmocerca spp. Cosmocercoides amapari n. sp. is the 29th species of the genus, the 5th from the Neotropical region, the third reported in Brazil, the second described from the Amazon region and the first belonging to the Neotropical region with molecular data.

Morphology and molecular characterization of Polystoma goeldii n. sp. (Monogenea, Polystomatidae) parasite from the urinary bladder of Physalaemus ephippifer (Steindachner) (Anura, Leptodactylidae).

Polystomatid flatworms of amphibians are represented in the Neotropical realm by species of Mesopolystoma, Nanopolystoma, Parapseudopolystoma, Polystoma, Riojatrema and Wetapolystoma but only species of Polystoma are known from Brazil, namely Polystoma cuvieri, P. knoffi, P. lopezromani and P. travassosi. During a survey of monogeneans infecting amphibians in the north-eastern region of Pará State, the Cayenne Caecilian Typhlonectes compressicauda was found to be infected with Nanopolystoma tinsleyi and the Veined Tree Frog Trachycephalus typhonius was found to harbor Polystoma lopezromani. A yet unknown species of Polystoma was also encountered in the urinary bladder of the Steindachner's Dwarf Frog, Physalaemus ephippifer. This new species, which is the second species reported from Physalaemus spp., is described herein as Polystoma goeldii n. sp. and its life cycle is also illustrated. The new species can be distinguished from Polystoma spp. from other neotropical realm by a combination of characteristics, including hamuli morphology, outer/inner hamuli length ratio, haptor/total body length ratio, genital bulb/total body length ratio, genital spine number and COI molecular characters.

Larval Digenean Parasitizing Amphibian Hosts from the Argentinian Chaco Region.

PURPOSE: The diversity of larval digenetic trematodes can provide information on one or more intermediate hosts prior to maturation into the definitive host; on host activity and distribution; and in some cases, on environmental perturbations. In this context, the goal of the present study was to analyse the trematode larvae found in adult amphibians collected from the Argentinian Chaco Region. Few studies have been reported on the systematics of larval digeneans in amphibians. METHODS: A total of 167 specimens of frogs (Leptodactylus macrosternum, Leptodactylus latinasus, Lepidobatrachus laevis, Lepidobatrachus llanensis and Lysapsus limellum) and toads (Rhinella bergi) were examined for larval digeneans. Frogs and toads were collected in two Argentinian ecoregions (Dry Chaco and Humid Chaco); between June 2002 and December 2019. Morphology of each taxon was studied in detail using light microscopy and scanning electron microscopy (SEM). RESULTS: Fourteen different taxa of the families Diplostomidae (Alariinae gen sp., Didelphodiplostomum sp., Pharingostomoides sp. and Tylodelphys sp.), Proterodiplostomidae (Heterodiplostomum lanceolatum), and Strigeidae (Strigea spp.) were found infecting the body cavity, mesentery, muscle, fluid in the spinal cord canal, and cranial cavity of amphibians. All species are described and illustrated, and their life cycles are briefly discussed. CONCLUSION: These infections provide new information on the morphology, morphometry, and composition of the diversity of mesocercariae and metacercariae in amphibians, thus contributing to the knowledge of potential intermediate hosts. In addition, our results serve as an indicator of parasite and host biodiversity in different ecoregions of the Gran Chaco.

Molecular data reveal a new species of Seuratascaris Sprent, 1985 (Nematoda: Ascaridoidea) from Quasipaa exilispinosa (Liu & Hu) (Amphibia: Anura).

The genus Seuratascaris Sprent, 1985 is a group of obligate nematode parasites of amphibians. In the present study, a new species of Seuratascaris, S. physalis sp. n. was described using light and scanning electron microscopy based on specimens collected from Quasipaa exilispinosa (Liu & Hu) (Amphibia: Anura) in China. The new species differs from S. numidica (Seurat, 1917) by the cuticle of the cervical region distinctly inflated to form a cephalic vesicle-like structure and the absence of single medio-ventral precloacal papilla. The molecular characterization of the nuclear large ribosomal DNA (28S) and internal transcribed spacer (ITS) and the mitochondrial cytochrome c oxidase subunit 1 (cox1), cytochrome c oxidase subunit 2 (cox2) and 12S small subunit ribosomal RNA gene of S. physalis sp. n., together with the 28S, cox2 and 12S of S. numidica are provided for the first time. Molecular analysis revealed the presence of high level of interspecific genetic variation between the two species in the ITS (5.50%), cox1 (13.3%), cox2 (10.6%) and 12S regions (10.5%), which strongly supported that S. physalis sp. n. represented a different species from S. numidica. Angusticaecum ranae Wang, Zhao & Chen, 1978 reported from the frog Quasipaa spinosa (David) (Anura: Dicroglossidae) in China was transferred into the genus Seuratascaris as S. ranae (Wang, Zhao & Chen, 1978) comb. n. based on the morphology of lips and the presence of very short and robust spicules without alae and small numbers of precloacal papillae. The present study provided useful genetic data for molecular identification of species of Seuratascaris and provides the foundation for being able to determine if S. numidica represents a species complex of some sibling species or a single species.

Diversity of Haemogregarine Parasites Infecting Brazilian Anurans, with a Description of New Species of Dactylosoma (Apicomplexa: Adeleorina: Dactylosomatidae).

PURPOSE: Brazilian anurans are considered the most diverse and species rich around the world. Although in recent years there has been a strong focus on research related to this group of animals, their parasites have not received the same attention. Thus, this study aimed to provide morphological and molecular data on haemogregarines biodiversity infecting Brazilian anurans. METHODS: During 2020, 116 anurans were collected from four Brazilian States and their blood and fragment of organs were screened for haemogregarine parasites. RESULTS: From the total, seven (6.03%) animals were found infected with species of Hepatozoon and Dactylosoma. Based on the morphological and molecular analysis, four anurans were found infected with Hepatozoon latrensis. The phylogenetic analysis has shown the isolates from this study grouping with the Brazilian anuran Hepatozoon clade, also with gene similarity ranging from 99.70 to 100% to H. latrensis isolates available on GenBank. Furthermore, three specimens (Trachycephalus typhonius, Leptodactylus latrans, and Rhinella diptycha) were infected with the same species of Dactylosoma (100% genetic similarity), with a genetic similarity of 98.56% to Dactylosoma piperis the only other species described in Brazil. In support of the molecular data, different morphological characters were observed in the blood smears as compared to D. piperis, suggesting that the species of Dactylosoma from the present study infecting three different species of Brazilian anurans is an undescribed species. CONCLUSION: Thus, this study increases the knowledge of Brazilian anuran blood parasites and demonstrates the importance of using integrative approaches for the diagnosis of haemoparasites.

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.

Endoparasite community of anurans from an altitudinal rainforest enclave in a Brazilian semiarid area.

In the present study, we aimed to describe the composition of endoparasites associated with anurans from an altitudinal rainforest enclave in northeastern Brazil. Additionally, we tested if microhabitat use influences endoparasite abundance and richness, as well as the hypothesis that larger frogs tend to be more parasitized. We sampled 306 individuals from 25 anuran species that were necropsied and analysed using a stereomicroscope. The total endoparasite prevalence was 79.08%, with a parasitic community consisting of 46 taxa. Overall, we found the common pattern described for Neotropical amphibians, which is the predominance of generalist and direct-cycle parasites. Twenty new host records and two possible new parasite species were found, highlighting the importance of this type of inventory. We also observed that microhabitat use was associated with a significant difference in parasite richness between groups, in which arboreal and terrestrial species, and aquatic and arboreal species contributed to these differences. Moreover, larger frogs tended to be more parasitized regarding only an interspecific view. Our results suggest that parasite richness is directly related to infection cycle and how the host exploits its habitat.

First molecular assessment on Cosmocerca spp. from Brazilian anurans and description of a new species of Cosmocerca (Ascaridomorpha: Cosmocercoidea) from the white-spotted humming frog Chiasmocleis albopunctata (Boettger, 1885) (Anura: Microhylidae).

Cosmocerca spp. are common nematode parasites of amphibians. We provide herein molecular data for two species of Cosmocerca and describe a new species, Cosmocerca albopunctata n. sp., using light microscopy and molecular data (cytochrome c oxidase subunit 1 - COI mtDNA). Cosmocerca albopunctata n. sp. can be easily distinguished from other congeneric species by the combination of characteristics such as body size, length of spicules and gubernaculum, and the arrangements and number of caudal papillae (7 + 1:1 + 1:6). The phylogenetic results based on the partial COI mtDNA sequences clustered the new species in a monophyletic clade along with the other sequences of Cosmocerca spp. Therefore, our results contribute to the knowledge about the species diversity and genetic data for Cosmocerca spp. in the Neotropical region.