Abstract <p>Serpentine habitats constitute biodiversity hotspots due to their unique features, harboring endemic-rich habitats. While the structure and ecology of their flora has been a focus of scientific research in Cuba for decades, their fauna has been less surveyed, particularly for butterflies. This research comparatively describes butterfly diversity of Lomas de Galindo, a fragmented serpentine area of western Cuba. Four one-h surveys were conducted between 09:30 and 13:30 h, in dry serpentine-scrub woodlands and disturbed vegetation habitats, every month from June 2019 to March 2020. Total species richness and richness per assemblage were estimated through rarefaction curves and sampling completeness curves. Species were classified according to residence status and life strategy, and butterfly abundance was estimated monthly. Rank-abundance curves were constructed to compare structure, and differences in composition were estimated through spatial replacement, non-metric multidimensional scaling and one-way analysis of similarities. We recorded 103 species belonging to all six butterfly families present in Cuba, achieving a high sample coverage and with a maximum expected richness of 119 species, very high in comparison to other Cuban localities, likely related to its serpentine nature and geographical placement. Species richness was higher in the native habitat and abundance was higher on the disturbed vegetation. Compositional similarities can be explained by their floral resemblance and proximity, while structural differences could be related to their different disturbance degree. Temporal richness and abundance trends follow the typical pattern of Neotropical butterfly communities, likely related to seasonal environmental changes. The locality represents a butterfly diversity hotspot in Cuba and further studies employing more data should contribute to understand the drivers of this previously non-surveyed diversity and to its conservation.</p> Implications for insect conservation <p>Our results highlight the elevated butterfly diversity and endemism present in serpentine areas, demonstrating the relevance of these for butterfly conservation, both in Cuba and worldwide. Furthermore, our richness and abundance patterns are the first described for these ecosystems, both in a conserved and a non-conserved area, serving as a baseline for future comparisons of similar habitats to assess biodiversity and habitat quality in them.</p>