First record of the genus Hoplisoma (Siluriformes: Callichthyidae) with an extension of its distribution to the Andean–Cuyan region, San Juan, Argentina

Knowledge of the geographical distribution of the ichthyofauna is key, as it provides the information needed for inventory and monitoring studies that detect endemism and/or introduced exotic species. Within Siluriformes, the family Callichthyidae, which comprises the subfamilies Corydoradinae and Callichthyinae, is recognized as the third largest family within the order. The Callichthyidae family, especially the subfamily Corydoradinae, comprises more than 200 species distributed throughout South America, showing notable morphological diversity and a range of habitats, from fast-flowing piedmont streams with sandy or rocky bottoms to lowland pools with muddy bottoms. In this work, the presence of a Callichthyidae species is reported and confirmed for the first time, with a voucher specimen, in the province of San Juan, and the geographical distribution range of the genus Hoplisoma is expanded to the Andean–Cuyan region of Argentina. The collected specimens were captured at the outflow of the José Ignacio de la Roza dam in San Juan province for taxonomic identification. The methodology proposed by Díaz et al. (2024) was followed. It was determined that these specimens correspond to the genus Hoplisoma, with diagnostic features similar to those of species such as H. osvaldoi and H. paleatus.