EN
Skrjabinodon castillensis is mentioned and illustrated here, based on specimens found in the largeintestines of Liolaemus gracielae(Squamata: Liolaemidae) collected in San Juan province, Argentina. The speciesfound is assigned to Skrjabinodon based lateral alae present in males. Lateral alae beginning midway between lips andnerve ring and ending just posterior to first pair of caudal papillae. In males, caudal alae absent, paired caudal papillaepresent. The species recorded in this study differs from all other species assigned to Skrjabinodonby morphology andnumber of tail filament spines. Skrjabinodon castillensis is the ninth species from the Neotropical realm and the onlyspecies of this genus known from Argentina.