Tail autotomy acts as anti-predatory mechanism in a great diversity of lizard species. Research links tail loss with various aspects of lizard life history. However, parasitic aspects are not taken into consideration, despite being a variable that greatly influences reptile ecology. For the first time, it is proposed that the existence of a relationship between the caudal autotomy of a lizard species is related to its parasitic condition. We studied 30 adult specimens of Liolaemus darwinii Bell, 1843 in the desert of Monte, San Juan province, Argentina. Autotomy was used as a direct measure of predator-prey interaction. A series of variables were analyzed that could be related to tail autotomy. The following variables were studied using generalized linear models: sex, environments (disturbed vs. conserved), condition (parasitized vs. not parasitized), parasitic intensity, weights (g) and...

Paraspidodera Travassos, 1914 is a genus of nematodes that parasitize rodents from the order Rodentia in South America. The objective of the present study is to document the first record of nematodes in the rodent Ctenomys eileenae Teta, Jayat, Alvarado-Larios, Ojeda, Cuello & D'Elía, 2023 in the province of San Juan, Argentina. For this, the gastrointestinal content of a female specimen of C. eileenae from the department of Iglesia was analyzed. Examination of the long intestine revealed the presence of Paraspidodera uncinata (Rudolphi, 1819) (Spirurida: Aspidoderidae). This study provides novel information on parasitism in rodents in Argentina, representing the first record of this nematode species in C. eileenae in the country and the first mention for the province of San Juan.

Nematodes of the genus Litomosoides Chandler, 1931 are body cavity parasites of a wide variety of hosts including bats, marsupials and rodents. The present study documents the first record of Litomosoides pardinasi Notarnicola & Navone 2011 in the rodent Abrothrix andina (Philippi, 1858) in San Juan Province, Argentina. Male nematodes of L. pardinasiwere characterized by a right spicule with a heel-like structure and a cuticularized terminal cap. A left spicule with a handle longer than the lamina and four pairs of postcloacal papillae. Females presented a vulva that is posterior to the esophagus-intestine intersection. This study provides novel information on the parasitism of A. andina in Argentina, representing the first record of this species of nematode in this rodent in the country and the first mention for the province of San Juan.

Nematodes of the genus Syphacia sp. (family Oxyuridae) parasitize the cecum of rodents belonging to the families Cricetidae, Muridae and Sciuridae. This study reports for the first time the presence of Syphacia sp. in San Juan province and expands the knowledge about its parasitism in the rodent Graomys griseoflavus (Waterhouse, 1837), both at provincial and national level. These observations constitute a novel contribution to the knowledge of the helminthofauna associated with G. griseoflavus in San Juan and Argentina.

In Argentina, there is one record of the nematode Trichuris dolichotis Morini, Boero & Rodriguez, 1955 (Nematoda: Trichuridae) parasitizing the mara Dolichotis patagonum (Zimmermann, 1780), which corresponds to its original description in 1955. In June 2023, at the Wildlife Rehabilitation Center, San Juan province, a specimen of mara male D. patagonum died and the necropsy´s results are under investigation at the moment. The post-mortem identified (n= 5) female nematodes of T. dolichotis in the intestine. In the present study we present the second record after 58 years of not reporting its presence, being the first record for the province of San Juan and the second for Argentina. The present work contributes to the knowledge of the mammalian parasite fauna of Argentina.

The endoparasitic fauna of four mammal species was analyzed: Puma concolor (Linnaeus, 1771) (cougar), Lycalopex gymnocercus (Fischer, 1814) (grey fox), Myocastor coypus (Molina 1782) (coipus) and Tolypeutes matacus (Linnaeus, 1758) (armadillo). These specimens entered the Center for Wildlife Rehabilitation, Environmental Education and Responsible Recreation located in the province of San Juan, Argentina. Out of the four mammal species, three died on the spot. The necropsy of L. gymnocercus, M. coypus and T. matacus was carried out, and it was evidenced the presence of three species of parasitic nematodes: Physaloptera clausa Rudolphi, 1819 (Physalopteridae) in L. gymnocercus; Trichuris myocastoris Enigk, 1933 (Trichuridae) in M. coypus; and adult females of Aspidodera sp. Railliet & Henry, 1912 in T. matacus. Regarding P. concolor, the expulsion of nematodes was orally, determining t...