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).

Endoparasite community structure of an anuran assemblage in the Caatinga, Northeastern Neotropical Region.

Amphibians are a widespread Chordata taxon and are important for maintaining the balance of both terrestrial and aquatic ecosystems. Brazil has a rich amphibian fauna; however, little is known about the role of their ecology and phylogenetic relationships during the assembly processes of associated endoparasite communities. Herein, we describe an endoparasite community in an anuran assemblage in the Caatinga, a unique biome of dry forests in north-eastern Brazil. We studied endoparasite diversity, as well as the effects of body length, body mass, body volume and sex on parasite abundance. We also investigated the influence of ecological and historical factors and anuran microhabitat use on endoparasite composition. We analysed individuals from 13 anuran species distributed across five families: Odontophrynidae (Proceratophrys cristiceps); Leptodactylidae (Leptodactylus fuscus, Leptodactylus vastus, Leptodactylus macrosternum, Leptodactylus troglodytes and Physalaemus cuvieri); Hylidae (Pithecopus gonzagai, Scinax x-signatus, Boana raniceps and Dendropsophus nanus); Bufonidae (Rhinella diptycha and Rhinella granulosa); and Microhylidae (Dermatonotus muelleri). We found nine species of endoparasites, including seven nematodes (Aplectana membranosa, Cosmocerca sp., Oswaldocruzia mazzai, Raillietnema spectans, Rhabdias fuelleborni, Schrankiana sp. and Physaloptera sp.), one species of Trematoda (Glypthelmins pseudium) and one non-identified cestode. There was no significant relationship between endoparasite abundance and host body length, body mass, body volume and sex. A phylogenetic principal component analysis showed that ecological factors had a greater influence on endoparasite assemblage than historical factors. Similarly, our results showed that ecological factors had a greater influence on anuran microhabitat use compared to historical factors, which contributed to the generalist characteristics presented by most of the sampled endoparasite species.

Parasitic Infection Patterns in Coleodactylus Meridionalis (Squamata: Sphaerodactylidae) from Atlantic Forest Fragments, Northeast of The Neotropical Region.

Studies that seek to understand which factors influence the patterns of infection in the lizard Coleodactylus meridionalis are non-existent. In this way, we recorded the infection rates for these lizards from three different sized fragments of the Atlantic rainforest and investigated if there is influence of the size, mass and sex of the host regarding the endoparasite abundance. In addition, we investigated if there were possible associations between the host's diet and parasitism, by calculating the diet niche breadth (based on the prey number of pooled stomachs) for each host population and comparing the diet between fragments and sexes (from the three sampled fragments). We collected 38 lizards across the three sampled forest fragments. We only found parasites in the lizards sampled from the smallest of the three forest fragments which included: Physaloptera lutzi, Haplometroides odhneri and Oligacanthorhynchus sp. For this population, lizards with greater length and body mass have a greater endoparasite abundance. In addition, based on the results obtained in our study, the diet of the lizards varies in food composition between sampled populations. Finally, knowing that among the infected lizards there is no sexual dimorphism in relation to size and body mass and that the stomach sampling for this population is insufficient to calculate the indexes related to the food niche; we used the number of prey lizards from all populations, thus we were able to associate the fact that female lizards have a greater endoparasite abundance due to variations in food composition between sexes.

Using lizards to evaluate the influence of average abundance on the variance of endoparasites in semiarid areas: dispersion and assemblage structure.

The distribution of parasites within host populations and communities, and the mechanisms responsible for these patterns, are poorly understood aspects of wildlife parasitology. Here, we evaluate the influence of the average abundance of endoparasite variance, using endoparasites of lizards from the Caatinga domain (semiarid region), north-eastern Brazil. We hypothesized that, due to the high number of generalist endoparasite species, they may occur randomly throughout host populations in an aggregate pattern. In addition, we evaluated the degree to which sample variance is influenced by the average abundance of endoparasite species, patterns of co-occurrence and dominance among endoparasite species and similarities between abundance and the richness of endoparasite infracommunities in several host species. Between September 2015 and February 2016, 2141 lizards (1233 infected) from 16 species were collected from six Caatinga areas. In total, 25,687 endoparasites were collected, which belonged to 13 species including nematodes, pentastomids, cestodes, trematodes and acanthocephalans. Parasite-host associations documented here included 39 newly identified interactions. Endoparasites occurred in a typical aggregate pattern of distribution within their hosts; there was no measurable preference related to the acquisition of hosts by endoparasites. Despite the new records, endoparasites found were commonly associated with lizards in Caatinga environments, which may reflect fauna composed of generalist endoparasite species.

Raillietiella Mottae (Pentastomida: Raillietiellidae) Parasitizing Four Species of Gekkota Lizards (Gekkonidae and Phyllodactylidae) in the Brazilian Caatinga.

We tested the role of sex, size, and mass of the lizards Phyllopezus pollicaris, Gymnodactylus geckoides, Hemidactylus agrius, Lygodactylus klugei, and Hemidactylus brasilianus on the rates of pentastomid infection in the Brazilian Caatinga. We collected 355 individuals of these five species, of which four (prevalence of infection: P. pollicaris 15.9 %, G. geckoides 1.4 %, H. agrius 28.57 %, and H. brasilianus 4.16 %) were infected by Raillietiella mottae. Parasite abundance was influenced by host body size and mass only in P. pollicaris. Host sex did not infl uence the abundance of parasites in any species. Hemidactylus agrius, G. geckoides, and H. brasilianus are three new host records for pentastomids.

Helminths Infecting Dryadosaura Nordestina (Squamata: Gymnophthalmidae) from Atlantic Forest, Northeastern Brazil.

We analyzed the patterns of infection by helminths in populations of the Gymnophthalmidae lizard Dryadosaura nordestina from three Atlantic Forest fragments in Northeast Brazil. Prevalence and mean intensity of infection by location showed the following results: ARIE Mata de Goiamunduba (60.8 % and 10.4 ± 8), RPPN Engenho Gargaú (83.3 % and 20.8 ± 19.7) and Benjamim Maranhão Botanical Garden (70.4 % and 7.78 ± 5.8). We provide the first records of helminth infection for the lizard D. nordestina, in which three species of nematodes, Aplectana sp., Cosmocerca sp. and Physaloptera lutzi and one trematode Haplometroides odhneri were recovered. Trematodes of the genus Haplometroides were previously known as parasites only in snake and amphisbaenian hosts in South America. Now, our study provides the first record of a species belonging to this genus parasitizing lizards. In conclusion, our study shows that D. nordestina have a depleted helminth fauna (three species at maximum), similar to other studies with lizards of this family in Brazil and that its parasite abundance is related to host snout-vent length, but not to the sex.

Nematodes associated with Iguana iguana (Linnaeus, 1758) (Squamata, Iguanidae) in Semi-arid areas of Northeastern Brazil / Nematoda associados a Iguana iguana (Linnaeus, 1758) (Squamata: Iguanidae) em áreas do semi-árido do nordeste do Brasil

Abstract Nematodes were analyzed in Iguana iguana, a large lizard Iguanidae that is widely distributed throughout the Americas. The aims of the study were investigate the helminths associated with the lizard, I. iguana in semi-arid areas of northeastern Brazil and analyze the parasitological indices (prevalence, and mean intensity of infection). A total of 18 specimens of I. iguana were examined (8 males and 10 females). The overall prevalence of infection was 66.6% (12/18), while in males, it was 75% (6/8) and in females, 60% (6/10). Iguana iguana was identified as a new host for Physaloptera sp., Atractis sp., Piratuba sp. and Subulura sp. This registered contributes to the knowledge of helminth diversity associated with this host.

Resumo Foram analisados os nematóides em Iguana iguana, um grande lagarto Iguanidae que possui ampla distribuição pelas Américas. Os objetivos do estudo foram investigar os helmintos associados ao lagarto I. iguana e seus índices parasitológicos (prevalência e intensidade média de infecção). Foram examinados 18 espécimes (oito machos e 10 fêmeas). A prevalência total foi de 66,6% (12/18), nos machos foi de 75% (6/8) e nas fêmeas 60% (6/10). Iguana iguana foi identificado como um novo hospedeiro para Physaloptera sp., Atractis sp., Piratuba sp., e Subulura sp. Este registro contribui para o conhecimento da diversidade de helmintos associados a este hospedeiro.

Helminths of the Lizard Salvator merianae (Squamata, Teiidae) in the Caatinga, Northeastern Brazil / Helmintos do lagarto Salvator merianae (Squamata, Teiidae) na Caatinga, Nordeste do Brasil

Abstract The lizard Salvator merianae is a widely distributed species in South America, occurring from southern Amazonia to the eastern Andes and northern Patagonia. Studies on the parasitic fauna of this lizard have revealed that it is a host for helminths in various Brazilian biomes. The present work provides new parasitological data on the gastrointestinal nematodes associated with the lizard S. merianae. Sixteen specimens were analyzed from nine different locations in a semi-arid region in northeastern Brazil. Five species of nematodes were identified. Oswaldofilaria petersi was first recorded as a parasite of the S. merianae, thus increasing the knowledge of the fauna of parasites that infect large Neotropical lizards.

Resumo O lagarto Salvator merianae é uma espécie bem distribuída na América do Sul, ocorrendo do sul da Amazônia até o leste dos Andes e norte da Patagônia. Estudos com a fauna parasitária desse lagarto revelaram que ele hospeda helmintos em vários biomas brasileiros. O presente trabalho fornece novo dado parasitológico sobre nematoda gastrointestinal associado ao lagarto S. merianae. Dezesseis amostras foram analisadas a partir de nove localidades diferentes na região semiárida do nordeste do Brasil. Foram identificadas cinco espécies de nematóide. Oswaldofilaria petersi foi registrado pela primeira vez parasitando S. merianae, aumentando assim o conhecimento da fauna de parasitas que infectam grandes lagartos neotropicais.

Helminths of the Lizard Salvator merianae (Squamata, Teiidae) in the Caatinga, Northeastern Brazil.

The lizard Salvator merianae is a widely distributed species in South America, occurring from southern Amazonia to the eastern Andes and northern Patagonia. Studies on the parasitic fauna of this lizard have revealed that it is a host for helminths in various Brazilian biomes. The present work provides new parasitological data on the gastrointestinal nematodes associated with the lizard S. merianae. Sixteen specimens were analyzed from nine different locations in a semi-arid region in northeastern Brazil. Five species of nematodes were identified. Oswaldofilaria petersi was first recorded as a parasite of the S. merianae, thus increasing the knowledge of the fauna of parasites that infect large Neotropical lizards.

Nematodes associated with Iguana iguana (Linnaeus, 1758) (Squamata, Iguanidae) in Semi-arid areas of Northeastern Brazil.

Nematodes were analyzed in Iguana iguana, a large lizard Iguanidae that is widely distributed throughout the Americas. The aims of the study were investigate the helminths associated with the lizard, I. iguana in semi-arid areas of northeastern Brazil and analyze the parasitological indices (prevalence, and mean intensity of infection). A total of 18 specimens of I. iguana were examined (8 males and 10 females). The overall prevalence of infection was 66.6% (12/18), while in males, it was 75% (6/8) and in females, 60% (6/10). Iguana iguana was identified as a new host for Physaloptera sp., Atractis sp., Piratuba sp. and Subulura sp. This registered contributes to the knowledge of helminth diversity associated with this host.

Helminths and Pentastomida of two synanthropic gecko lizards, Hemidactylus mabouia and Phyllopezus pollicaris, in an urban area in Northeastern Brazil.

Helminths and pentastomids were examined in exotic Hemidactylus mabouia and native Phyllopezus pollicaris lizards, living synanthropically in an urban area in the municipality of Crato, Ceará state, northeastern Brazil. A total of 194 lizards were collected, being 76 specimens of H. mabouia e 118 specimens of P. pollicaris. Six parasite species were found infecting H. mabouia: the cestode Oochoristica sp., the nematodes Parapharyngodon sceleratus, Physaloptera retusa, Physalopteroides venancioi, and Spauligodon oxkutzcabiensis and the pentastomid Raillietiella mottae; while four parasite species were found associated with P. pollicaris: Oochoristica sp., P. sceleratus, P. retusa, and S. oxkutzcabiensis. Three new host records were reported: P. retusa infecting H. mabouia and P. retusa and Oochoristica sp. infecting P. pollicaris. About 75% of the parasites species found were shared by both lizards. Moreover, H. mabouia showed greater diversity than P. pollicaris (6 versus 4 species), while P. pollicaris had higher intensity of infection than H. mabouia (1536 versus 121 specimens).