In the Argentinean Gran Chaco, numerous investigations have dealt with the diversity of vertebrates, including herps. As for the parasitofauna of these organisms, some groups, such as amphibians, have been more studied; however, from a biogeographic perspective, most of these studies were carried out in a different area, the Humid Chaco. The goal of this work is to present the nematofauna found in six species of amphibians, namely Rhinella diptycha , Chacophrys pierottii , Ceratophrys cranwelli , Scinax nasicus , Leptodactylus bufonius , and Odontophrynus lavillai , collected in different locations within the Dry Chaco, in the department of Matacos, Formosa, Argentina. In a total of 34 amphibians analyzed, we found 1,526 nematode parasites (total prevalence: 61.7%; total mean intensity: 72.6±90.3; total mean abundance: 46.2±79.7), belonging to 9 taxa: adults of Rhabdias sp., Oswaldocruzia sp., O. subauricularis , Schulzia travassossi , Aplectana hylambatis , Cosmocerca podicipinus , Oxyascaris caudacutus , Schrankiana formosula , and larvae of Physaloptera sp. These nematodes were collected from the lungs, small intestine, large intestine, gastric mucosa, and gallbladder of hosts. This work is the first record of helminths from C. pierottii and O. lavillai and the first record of nematodes from Ce. cranwelli throughout its geographical range. The species Oswaldocruzia subauricularis (Molineidae) and Schrankiana formosula (Atractidae) are recorded for the first time in Argentinean amphibians. Thus, we expand the knowledge of the biological diversity of helminth parasites of amphibians; this information, integrated into future and more comprehensive studies, will allow us to understand the factors that influence the patterns of host and geographic distribution, in an area with such extreme characteristics as the Dry Chaco.

Knowledge about endoparasites of snakes is essential to understand the ecology of both parasites and hosts. Herein, we present information on helminths parasitizing the black false boa Pseudoboa nigra in northeastern Brazil. We examined 32 specimens from five Brazilian states (Ceara, Piaui, Pernambuco, Maranhao and Rio Grande do Norte). We found six helminths taxa: two acanthocephalans ( Acanthocephalus sp. and Oligacanthorhychus sp.), three nematodes ( Hexametra boddaertii, Physaloptera sp. and Physalopteroides venancioi ), and one cestode ( Ophiotaenia sp . ). All parasites are reported for the first time infecting P. nigra , providing relevant information on infection patterns in this snake.

Lizards are hosts to a variety of parasites, but in South America only 15% of lizard species have been studied for helminths. In the present study, the component community of helminths associated with the gymnophthalmid Colobosauroides cearensis in an area of Caatinga (7°22’46.08” S, 38°38’47.87”W) is reported. We examined 91 specimens from the Brazilian state of Ceara, and five taxa of helminths were recovered: four Nematoda ( Parapharyngodon largitor, Spauligodon sp., Physaloptera sp . and Oswaldocruzia sp.) and one Cestoda ( Oochoristica sp.). Parapharyngodon largitor was the most prevalent species (61%), and presented the highest mean abundance of infection (1.60 ± 0.18). Lizard body size influenced the richness and abundance of helminths, while infection parameters were not related to lizard sex.

In this study, the Kinosternon scorpioides , Mesoclemmys tuberculata and Phrynops geoffroanus freshwater turtles collected in the Carius River, State of Ceara, were analysed as to their diet composition and presence of helminths. Among the 63 examined turtles 55 (87.3%) were parasitized. We found three Nematoda species ( Physaloptera retusa , Serpinema monospiculatus and Spiroxys figueiredoi ) and one Trematoda species ( Gorgoderina sp.). Phrynops geoffroanus had the highest indexes of prevalence (97.56%) and mean intensity of infection (33.5), followed by M. tuberculata (70% and 12.64, respectively) and K. scorpioides (50% and three, respectively). Host body size was positively related to helminths abundance in both male and female Chelidae species. A significant difference in helminths abundance between the sexes was found only in P. geoffroanus , where females had more parasites than males. Regarding diet, the main food items ingested by M. tuberculata were Odonata nymphs (Aeshnidae and Libellulidae), whilst P. geoffroanus feeds mainly on Diptera larvae (Chironomidae), Odonata nymph (Aeshnidae) and Notonectidae, and only seeds were found in the stomach contents of K. scorpioides . Here, we present the first record of S. monospiculatus parasitizing K. scorpioides , Gorgoderina sp. and P. retusa were reported for the first time in P. geoffroanus , and M. tuberculata represents a new host to P. retusa and S. figueiredoi .

Os animais silvestres podem ser considerados reservatorios de especies de varios parasitos. A ocorrencia de determinados agentes parasitarios pode fornecer informacoes importantes sobre a ecologia e o comportamento do hospedeiro e suas relacoes troficas. Dessa forma, este estudo teve por objetivo determinar a fauna parasitaria de animais silvestres do sul de Minas Gerais no periodo de janeiro a dezembro de 2011. Foi realizado um estudo transversal com uma amostra de conveniencia constituida por cadaveres de dois animais atropelados, que foram resgatados de rodovias e transportados para o Laboratorio de Anatomia Animal da Universidade Federal de Lavras (UFLA). Os exemplares foram inspecionados para verificacao da presenca de ectoparasitos e, em seguida, dissecados para recuperacao do conteudo gastrintestinal e deteccao de helmintos. Nao foram identificados ectoparasitos nos dois animais, ambos da especie Conepatus semistriatus (jaritataca), mas foi identificada a presenca de helmintos do genero Physaloptera no estomago de um especime.

Tropiduridae (Squamata: Iguania) is a lizard taxon widely distributed in the neotropics. Among its representatives, some species are classified as generalists regarding habitat usage. Others exhibit a very restricted and probably relict distribu- tion, and are strongly associated with predominantly sandy and dry habitats. Within this rather ecologically similar than phylogenetically closely related group we examined specimens of Eurolophosaurus amathites , E. divaricatus, Tropidurus hygomi, T. psam- monastes for endoparasites. In all four species examined we recorded parasitic nema- todes (Nemathelminthes: Nematoda). At least three nematode species were recovered: Parapharyngodon sp., Physaloptera lutzi and Strongyluris oscari, with Ph. lutzi being the most abundant parasite encountered in all lizard species examined. In spite of the hosts' habitat specialization, these parasites are also found frequently in non-psammo - philous tropidurid species as well as in other squamates. Individual species richness per lizard was low, with usually just one species parasitizing at a time. These are the first parasites registered for these tropidurids and constitute a total of six new host records.