Reptiles constitute the most diverse group of terrestrial vertebrates, with more than 12,500 species occupying nearly every non-polar ecosystem (Uetz et al., 2025[reptile-database.org]). Their evolutionary history spans over 240 million years, during which they have colonised all continents except Antarctica, and an exceptional range of ecological niches, from hyper-arid deserts and tropical rainforests to alpine habitats, subterranean environments, and marine ecosystems (Vitt & Caldwell, 2014 [DOI:]). In the Mediterranean basin alone, more than 350 reptile species are present.

Despite their ecological and evolutionary importance, genomic resources for reptiles, and particularly high-quality reference genomes, have historically lagged behind those available for mammals and birds (Card et al., 2023[DOI:10.3390/ani13030471]). Furthermore, available genomes are unevenly distributed across clades. While some groups, such as lacertid lizards of the genus Podarcis, have experienced a recent increase in genomic resources, many reptile lineages remain poorly represented or completely absent from current genomic databases.

Recent efforts funded under the Catalan Iniatitive for the Earth BioGenome Project (CBP) have demonstrated that reptile genomes can be assembled efficiently and at high quality using current sequencing technologies. 

One of the main objectives of the second phase of the CBP is to scale up the generation of reference genomes (Objective A.i). Reptiles provide a unique opportunity to achieve this goal, as only 12 native species remain to be sequenced, and previous CBP projects have already demonstrated high success rates in this group. Completing the PPCC native reptile reference genome catalogue would represent a major milestone for the CBP, establishing Reptilia as the first fully genomically characterised major faunal group within the CBP framework. Beyond generating high-quality genomic resources for all native reptile species of the region, the project will provide an exceptional comparative framework to investigate genome evolution, chromosomal diversification, adaptation, and biodiversity conservation across an entire vertebrate class at a regional scale.

This project is funded by the grant IEC-BG5-2026-3 from the Institut d’Estudis Catalans (Institute of Catalan Studies) within the framework of the Fifth Call for Biogenome Research Grants.

ROLE OF CNAG