Larvas de nematoides encontradas em anfíbios no nordeste da Argentin

Five species of amphibians, Leptodactylus podicipinus, Scinax acuminatus, S. nasicus, Rhinella fernandezae and Pseudis paradoxa, were collected in Corrientes province, Argentina and searched for larval nematodes. All larval nematodes were found as cysts in the serous of the stomach of hosts. Were identified one superfamily, Seuratoidea; one genus, Spiroxys (Superfamily Gnathostomatoidea) and one family, Rhabdochonidae (Superfamily Thelazioidea). We present a description and illustrations of these taxa. These nematodes have an indirect life cycle and amphibians are infected by consuming invertebrate, the intermediate hosts. The genus Spiroxys and superfamily Seuratoidea were reported for the first time for Argentinean amphibians.Cinco espécies de anfíbios, Leptodactylus podicipinus, Scinax acuminatus, S. nasicus, Rhinella fernandezae e Pseudis paradoxa, foram coletadas na província de Corrientes, Argentina e pesquisadas para achar nematoides larvais. Todas as larvas foram encontradas como cisto na serosa do estômago dos hospedeiros. Foram identificadas uma superfamília, Seuratoidea, um gênero, Spiroxys (Superfamília Gnathostomatoidea) e uma família, Rhabdochonidae (Superfamília Thelazioidea). Apresentamos uma descrição e ilustrações dos táxons. Estes nematoides têm um ciclo de vida indireto e os anfíbios são infectados pelo consumo dos invertebrados, os hospedeiros intermediários. O gênero Spiroxys e a superfamília Seuratoidea são relatados pela primeira vez para anfíbios da Argentina.Fil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Hamann, Mónika Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Cosmocercid Nematodes of Three Species of Frogs (Anura: Hylidae) from Corrientes, Argentina

We collected 142 hylid frogs representing 3 species, chaco treefrog Hypsiboas raniceps, dwarf treefrog Dendropsophus nanus, and sanborn treefrog Dendropsophus sanborni, near the city of Corrientes, Corrientes Province, Argentina, between January 2002 and December 2003, and we examined them for nematodes. Two species of cosmocercid nematodes were found infecting the large intestine of these hosts. Cosmocerca parva was found infecting H. raniceps and D. sanborni, whereas Cosmocerca podicipinus was found infecting D. nanus. These nematode species are reported for the first time from these hylids from Corrientes, Argentina. KEY WORDS: Hylidae, Hypsiboas raniceps, Dendropsophus nanus, Dendropsophus sanborni, Nematoda, Cosmocerca parva, Cosmocerca podicipinus, Corrientes, Argentina.Fil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Hamann, Mónika Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Biodiversity of trematodes associated with amphibians from a variety of habitats in Corrientes Province, Argentina

The main goals of this study were to compare the richness of parasitic trematodes in amphibians with diverse habits (terrestrial, fossorial, semi-aquatic and arboreal), and to evaluate whether the composition of the trematode community is determined by ecological relationships. Specimens were collected between April 2001 and December 2006 from a common area (30 ha) in Corrientes Province, Argentina. Trematodes of amphibians in this area comprised a total of 19 species, and were dominated by common species. Larval trematodes presented highest species richness, with the metacercaria of Bursotrema tetracotyloides being dominant in the majority (78%) of the parasite communities. Adults of the trematode Catadiscus inopinatus were dominant in the majority (67%) of amphibians. The amphibians Leptodactylus latinasus, Leptodactylus bufonius and Scinax nasicus presented a high diversity of trematodes, whereas Leptodactylus chaquensis had the lowest diversity even though it presented with the highest species richness. The patterns of similarity among amphibian species showed groups linking with their habitats. Leptodactilid amphibians, with a generalist diet and an active foraging strategy showed highest infection rates with adult trematodes. The mean richness of trematode species related to host´s habitat preferences was higher in semi-aquatic amphibians. Results suggest that semi-aquatic amphibians, present in both aquatic and terrestrial environments, present a greater diversity of parasites as they have a higher rate of exposure to a wider range of prey species and, hence, to diverse infective states. The trematode composition is related to the diets and mobility of the host, and habitat.Fil: Hamann, Monika Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Nordeste. Centro de Ecologia Aplicada del Litoral (i); Argentina;Fil: Kehr, Arturo Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Nordeste. Centro de Ecologia Aplicada del Litoral (i); Argentina;Fil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Nordeste. Centro de Ecologia Aplicada del Litoral (i); Argentina

Morphological variation of aplectana hylambatis (Nematoda: Cosmocercidae) from different anuran hosts and localities in Argentina

Aplectana hylambatis is a nematode witha wide geographic distribution and low host specificity. In spite of numerousreports, until this moment, the morphological variations between differenthosts and localities have not been studied. We studied 401 specimens collectedfrom five host species from seven localities in Argentina, and examined thefollowing morphological characters: mamelon-like cuticular protuberancesanterior to the vulva, structure of the gubernaculum and the spicules, numberand arrangement of caudal papillae, and the measurements of twelve charactersin females and eleven characters in males. The results showed that mamelon-likeprotuberances and caudal papillae varied in number and arrangement between differenthosts and localities. The metrical study revealed that five characters in malesand six in females contributed to variability; nine characters showedsignificant differences between host species and localities. Specimens of A.hylambatis collected from R. arenarum formed a group clearly differentiatedfrom the rest of the specimens. The results from this study highlight theimportance of examining as many specimens as possible from different hostsamples and from several localities to cover the intraspecific variations.Fil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Gómez, Valeria Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Hamann, Mónika Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Community Structure of Helminth Parasites of Leptodactylus bufonius (Anura: Leptodactylidae) from Northeastern Argentina

The main goals of this study were to determine the richness and diversity of helminth parasites of Leptodactylus bufonius at the component and infracommunity levels and evaluate whether the composition of the parasite community is determined by biotic and abiotic factors. In total, 76 specimens were collected near the city of Corrientes, Corrientes Province, Argentina. The helminth component community in L. bufonius in this area was comprised of 16 species. The predominant groups of helminth parasites (larval and adult) were trematodes (50%) followed by nematodes (38%); other groups of parasites were represented by only 1 species (Cestoda: Cylindrotaenia sp. and Acanthocephala: Centrorhynchus sp.). Helminth species showed unequal abundances with a typical aggregated pattern of distribution. The prevalence of infection was 93% in specimens of L. bufonius examined. The main helminth species in the community was Aplectana hylambatis (importance value: I = 96.41), followed by Catadiscus inopinatus (I = 2.32). At the infracommunity level, the mean individual species richness was no more than 3 helminth species per infected host; the diversity and equitability of helminths were 0.18 ± 0.14 and 0.44 ± 0.32, respectively. The host body size was the main factor in determining the infrapopulation structure of various helminth species. Species richness was significantly and positively correlated with the host body size. Data revealed significant positive correlations between helminth species (Cat. inopinatus/Centrorhynchus sp. and A. hylambatis/Centrorhynchus sp.). A significant negative correlation was observed between A. hylambatis and C. podicipinus. Only 2 associations were found among the 7 species considered. The parasite community of L. bufonius showed wide variations in its helminth fauna and included helminths of aquatic and terrestrial habitats. The correspondence between host habits and parasite biology is reflected in the parasites harbored by these amphibian hosts.Fil: Hamann, Mónika Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Kehr, Arturo Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Metacercariae of Strigeidae Parasitizing Amphibians of the Chaco Region in Argentina

The goal of the present study was to analyze the metacercariae found in adultamphibians collected in the Argentinean Chaco region. A total of 194 frogs,Leptodactylus chaquensis, Leptodactylus latinasus, and Lepidobatrachus laevis wasexamined for digeneans. Three different larval trematodes of the genus Strigea(Digenea, Strigeidae) were found infecting the liver, mesentery, body cavity, andmuscle of frogs. These metacercariae are described and illustrated for the first time andprovide new information on the composition of metacercariae in amphibians, thuscontributing to the knowledge of larval trematodes biodiversity in the Neotropicalregion. We also present new information on the morphology and morphometry of strigeid metacercariae.Fil: Hamann, Mónika Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Fernández, María Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Primeiro estudo parasitológico em rã com garras Africano (Xenopus laevis, Anfibia) no Chile

Introduced species can arrive into new territories with parasites; however, these species are expected to face lower parasite richness than in their original regions. Both introduced hosts and parasites can affect native fauna. Since their release into the wild in Chile following laboratory use, Xenopus laevis Daudin, 1802 has widely spread throughout central Chile. The only pathogen described on the host is the fungus Batrachochytrium dendrobatidis Longcore, Pessier, Nichols, 1999; thus, this is the first parasitological study of this species in Chile. In 10 localities in central Chile, 179 specimens of X. laevis were captured and examined for parasites in the gastrointestinal tube, cavities, lungs, liver, and skin. Only nine specimens of the genus Contracaecum Railliet, Henry, 1912 were found in six specimens of X. laevis from a private dam in La Patagua. It is likely that these parasites originated from species of native birds. This is the first record of Contracaecum sp. in Chilean amphibians.Espécies exóticas podem se introduzir em um novo território com seus parasitas, porém nesses casos, a riqueza parasitária seria menor. Contudo, hospedeiros exóticos e seus parasitas associados podem afetar a fauna nativa. Depois de ser dispensado do uso em laboratórios e solto em ambientes naturais, Xenopus laevis Daudin, 1802 tem se espalhado massivamente no Chile central. O único patógeno descrito para este anuro é o fungo Batrachochytrium dendrobatidis Longcore, Pessier, Nichols, 1999. O presente estudo constitui a primeira pesquisa parasitológica realizada nesta espécie de rã introduzida no Chile. Em 10 localidades do Chile central, foram capturados 179 espécimes de X. laevis que foram examinadas em busca de parasitos dentro tubo digestivo, cavidades corporais, pulmões, fígado e pele. Nove espécimes do gênero Contracaecum Railliet, Henry, 1912 foram encontrados em seis espécimes de X. laevis de uma barragem em La Patagua. É provável que a origem destes parasitas sejam espécies de aves nativas. Este é o primeiro relato de Contracaecum sp. em anuros do Chile.Fil: Castillo, Cristóbal. Universidad de Concepción; ChileFil: Lobos, Gabriel. Universidad de Chile; ChileFil: González Acuña, Daniel. Universidad de Concepción; ChileFil: Moreno, Lucila. Universidad de Concepción. Facultad de Ciencias Naturales y Oceanografía; ChileFil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Landaeta-Aqueveque, Carlos. Universidad de Concepción; Chil

Nematodes of Amphibians from the South American Chaco: Distribution, Host Specificity and Ecological Aspects

This is the first review of the nematode parasites of amphibians from Dry Chaco (DC) and Humid Chaco (HC) ecoregions of South America, covering aspects related to their systematics, distribution, host range and ecology, including their life cycles. Of approximately 100 species of amphibians that inhabit these ecoregions, the nematode parasites of 32 species are known. The parasite species consisted of 51 taxa: 27 in HC and 18 in DC. The family Cosmocercidae alone included 18 species. Aplectana hylambatis and Cosmocerca podicipinus showed the widest geographical and host distribution. Leptodactylus bufonius and Rhinella major presented a high number of nematode parasites. The species richness of nematodes was related to the host body sizes and to the strategy to obtain prey. The mean species richness was higher in terrestrial amphibians with intermediate characteristics in the generalist–specialist spectrum in terms of diet, and in amphibians with intermediate characteristics between actively foraging and the “sit-and-wait” approach in terms of searching for prey. The patterns of similarity among amphibian species showed groups linking with their habitats. Nematodes usually have direct life cycles with the infectious form entering the host passively or actively. However, many amphibians are also involved in heteroxenous cycles that develop in the aquatic environment.Fil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Hamann, Mónika Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Duré Pitteri, Marta Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Presence of Kalicephalus subulatus Molin, 1861 (Nematoda, Diaphanocephalidae) in Waglers snake, Xenodon merremi from Argentina

This is the first record of the nematode parasite Kalicephalus subulatus (Strongylida, Diaphanocephalidae) in Wagler’s snakes, Xenodon merremi (Squamata, Colubridae), collected in Corrientes, Argentina. The species was observed using light and scanning electron microscope (SEM) and compared to previous studies from Tropical America. As for the metric characters, the specimens collected in Argentina are smaller than all of those found so far in other hosts. However, despite the differences in the measurements, some characters such as the dorsal lobe type III and the amphidelphic uterus allow its specific identification. Previously, this genus was found in X. merremi from Argentina but the absence of males precluded their specific identification.Fil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Schaefer, Eduardo Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Investigaciones Geohistóricas. Universidad Nacional del Nordeste. Instituto de Investigaciones Geohistóricas; ArgentinaFil: Duré Pitteri, Marta Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Parasite and reproductive features of Scinax nasicus (Anura: Hylidae) from a South American subtropical area

Desde febrero de 2002 a diciembre de 2004, se analizó la fauna de helmintos parásitos y las características reproductivas de Scinax nasicus en un área cercana a la ciudad de Corrientes, Argentina. La fauna de parásitos helmintos estuvo conformada por 15 especies de helmintos (larvas y adultos) incluyendo trematodes (73%), nematodes (20%) y acantocéfalos (7%). La especie Opisthogonimus sp. presentó la mayor prevalencia (41%) de infección. Los hospedadores definitivos de esta metacercaria son probablemente las serpientes. Scinax nasicus, interviene como segundo hospedador intermediario, infectándose por la penetración directa de cercarias. El número de óvulos maduros por hembra (complemento ovárico) osciló entre 413-3922, mientras que el diámetro medio de los óvulos fue de 0,76 ±0,17mm. Esta especie posee un patrón reproductivo prolongado.From February 2002 to December 2004, the helminth parasite fauna and reproductive features of the frog Scinax nasicus were studied from Corrientes city, Province of Corrientes, Argentina. The parasite richness was 15 species of helminths (larval and adult) including trematodes (73%), nematodes (20%) and acanthocephalans (7%). Opisthogonimus sp. showed the highest prevalence (41%). The definitive hosts of these larval trematodes are probably snakes; S. nasicus acts as second intermediate host, and become infected by direct penetration of cercariae. The number of mature ova per female ranged from 413 to 3922, and the mean mature ovum diameter was 0.76 ±0.17mm. This species has a prolonged reproductive pattern.Fil: Hamann, Mónika Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Kehr, Arturo Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Duré Pitteri, Marta Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Schaefer, Eduardo Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin