Hybridization in Canids—A Case Study of Pampas Fox (Lycalopex gymnocercus) and Domestic Dog (Canis lupus familiaris) Hybrid

SIMPLE SUMMARY: In South America, the natural habitats of wild canids have undergone significant environmental disruptions, leading to interactions between these animals and domestic dogs (Canis lupus familiaris). Previous studies have documented hybridization between wild canids and domestic dogs in North America and Europe. However, there have been no reports of such hybridization in South America until now. In 2021, a female canid from Vacaria in Rio Grande do Sul State, Brazil, was brought to the Center for Conservation and Rehabilitation of Wild Animals—Preserves. This animal exhibited unusual phenotypic characteristics, displaying intermediate traits between domestic dogs and wild canids. Based on these observations, we hypothesized that this animal might result from interspecific hybridization. Therefore, this study aimed to test this hypothesis using genetic and cytogenetic approaches. Our analysis suggests that the canid under investigation is a hybrid between the pampas fox and domestic dog, but future studies are necessary to investigate additional cases of this hybridization in nature. Therefore, the combination of genetic and cytogenetic markers proved valuable in elucidating this case of hybridization. To our knowledge, this represents the first documented case of hybridization between these two species. ABSTRACT: Hybridization between species with different evolutionary trajectories can be a powerful threat to wildlife conservation. Anthropogenic activities, such as agriculture and livestock, have led to the degradation and loss of natural habitats for wildlife. Consequently, the incidence of interspecific hybridization between wild and domestic species has increased, although cases involving species of different genera are rare. In Vacaria, a Southern city in Brazil, a female canid with a strange phenotype, which had characteristics between the phenotype of the domestic dog (Canis familiaris) and that of the pampas fox (Lycalopex gymnocercus), was found. Our analysis suggests that the animal is a hybrid between a domestic dog and a pampas fox, but future studies are necessary to investigate additional cases of this hybridization in nature. This finding worries for the conservation of wild canids in South America, especially concerning Lycalopex species. Hybridization with the domestic dog may have harmful effects on pampas fox populations due to the potential for introgression and disease transmission by the domestic dog. Therefore, future studies to explore the consequences of hybridization on genetics, ecology, and behavior of wild populations will be essential to improve the conservation of this species.