Data from: Ancestral hybridization yields evolutionary distinct hybrids lineages and species boundaries in crocodiles, posing unique conservation conundrums

Interspecific hybridization can lead to adaptation and speciation,
especially in the context of recent radiations. The emblematic Crocodylus
(true crocodiles) is the most broadly distributed, ecologically diverse,
and species-rich crocodylian genus. Nonetheless, their within-species
evolutionary processes are poorly resolved mainly due to their potential
for hybridization. Notably, the evolutionary outcomes when hybridization
is ancient and involves long-lived species, like crocodiles, remain
largely unexplored. Here, we evaluate the genomic admixture between the
American (Crocodylus acutus) and the Morelet’s (Crocodylus moreletii)
species, and demonstrate that this hybridization system challenges the
definition of species boundaries and poses a triple conservation
conundrum: what has been recognized as C. acutus is actually two distinct
species, therefore its taxonomic reassessment is needed; we identified two
evolutionary distinct hybrids lineages, which are genetically discernible
from the parental species; the remaining C. moreletii populations evidence
its likely extinction as a species and/or evolution via hybridization.
Hence, the crocodiles’ distinct species and hybrids lineages warrant
recognition and need urgent conservation efforts.