Genetic assessment of mating system, kinship, and population structure in the burrowing rodent Clyomys laticeps (Thomas, 1909)

Mating systems are a fundamental aspect of a species’ biology, often contributing to patterns of dispersal, kinship, and genetic structure. Although rodents in the family Echimyidae are taxonomically, morphologically, and ecologically diverse, little is known about their reproductive behavior, including its effects on demographic and genetic structure. To characterize the genetic mating system of the burrowing echimyid Clyomys laticeps , tissue samples were obtained from 53 individuals in Parque Estadual da Serra de Caldas Novas (GO, Brazil) between May 2018 and February 2020. Individual genotypes generated from 10 polymorphic microsatellite loci were used to test the predictions that 1) C. laticeps displays a polygynandrous mating system and 2) male-biased natal dispersal, consequently that 3) kin structure is more pronounced among females. Parentage assignment analyses revealed that both males and females produced offspring with multiple partners across different rounds of reproduction, indicating a polygynandrous mating system. Coefficients of relatedness among males did not differ from those among females, suggesting a lack of sex-biased dispersal and sex-based kin structure. Consistent with these findings, genetic variation within the study population was not strongly structured and no evidence of significant inbreeding was detected. Overall, dispersal patterns did not differ between male and female, and the frequency of dispersal seems to be sufficient to prevent significant inbreeding and spatial genetic structure within local populations of C. laticeps . More generally, our findings contribute to future studies aimed at assessing the adaptive bases for variation in behavior, demography, and genetic structure among burrow-dwelling echimyids and other rodent families.