A separate lineage
The study separated Nueces fish from the upper Frio River populations retained as Dionda serena. Both mitochondrial and nuclear evidence supported that distinction. Older accounts combining the Nueces and Frio populations under serena therefore describe a broader range than the revised species concept.
Sources: Phylogeny, diversity, and species delimitation of the North American Round-Nosed Minnows
Guide sources
Research reviewed 2026-10-19.
- Phylogeny, diversity, and species delimitation of the North American Round-Nosed Minnows — Molecular Phylogenetics and Evolution
