Data from: Coalescent-delimitation framework disentangles species boundaries within the Neotropical mouse-opossums subgenus Marmosops.

The Neotropics encompass a vast array of biomes and habitat types, making it one of the most critical regions for exploring cryptic and undiscovered biodiversity. However, it remains one of the least represented areas in genetic data within the tree of life. Advancing genetic studies at both intra- and interspecific levels in this region is therefore a key scientific priority to bridge gaps in our understanding of global biodiversity. Among the diverse Neotropical fauna, marsupials of the Marmosops subgenus inhabit a wide range of habitats, positioning them as an ideal group for investigating diversification processes in the Neotropics. Nonetheless, such studies are limited by unresolved species boundaries within certain groups of this subgenus.

In this study, we assess the evolutionary independence of 13 cryptic mtDNA haplogroups in Marmosops, previously identified through single-locus species delimitation analyses. Using a multi-locus dataset (12 unlinked nuclear loci and 1 mtDNA locus), we applied a Bayesian Multi-Species Coalescent framework in BPP, supplemented by a heuristic criterion (gdi) that incorporates the speciation-continuum concept into species delimitation. Our findings indicate that BPP supports all 13 haplogroups as distinct evolutionary lineages. However, the gdi heuristic revealed that these lineages span the full speciation continuum, with only 7 of the BPP-recognized lineages corresponding to “true” species. Of these 7, three are currently recognized as valid species, validating the robustness of our approach. Furthermore, ecogeographic data suggest that the remaining four lineages hold the potential to be recognized as new species pending further evidence.