Neogaerrhinum is a small genus of flowering plants in the family Plantaginaceae, placed within the tribe Antirrhineae — the same group that contains the familiar garden snapdragons (Antirrhinum). The genus comprises just two accepted species: Neogaerrhinum filipes and Neogaerrhinum strictum. Both were previously treated as New World members of Antirrhinum, but molecular phylogenetic work by Vargas et al. (2004) demonstrated that the New World lineages represent independent evolutionary origins distinct from the Old World core of that genus, leading to their recognition as a separate genus.
Like other members of the Antirrhineae, Neogaerrhinum plants bear the characteristic two-lipped (bilabiate) flowers associated with snapdragons, adapted for pollination by bees capable of forcing open the closed corolla. The genus name reflects its close relationship to and partial separation from the broader snapdragon alliance. With only two species, it is one of the smaller segregate genera that emerged from the reclassification of Antirrhinum following advances in molecular systematics.
Taxonomy Notes
Neogaerrhinum was segregated from Antirrhinum following molecular phylogenetic analysis (Vargas et al. 2004), which showed that New World Antirrhinum species form at least three independent lineages separate from the Old World clade. The genus belongs to tribe Antirrhineae in family Plantaginaceae (the family was formerly circumscribed as Scrophulariaceae before broader molecular reclassification).
