The volcano rabbit Romerolagus diazi is endemic to the mountains of central Mexico, where its habitat has been gradually destroyed to make way for agriculture, ranching and logging, and by forest fires. The volcano rabbit is categorized as Endangered on the IUCN Red List. We evaluated the relationship between the abundance of the volcano rabbit and vegetation structure at a small scale (0.25 ha). Using a general linear model we generated a set of 21 predictive models and proposed the best model as a habitat quality index. Our results suggest that greater height and cover of bunchgrasses and the presence of a shrub layer offer the volcano rabbit the best refuge from predators. The habitat quality index and the limited available habitat documented in our survey indicate that the populations of volcano rabbits in the study area are more threatened than previously thought. As R. diazi is a habitat specialist it does not have the option of moving to another habitat type.