Contributions to the knowledge of parasitic nematodes of amphibians from the Dry Chaco ecoregion of Argentina;
Contributions to the knowledge of parasitic nematodes of amphibians from the Dry Chaco ecoregion of Argentina

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 Chaco Seco, 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 Chaco Seco.

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.