<p>Non-native plants frequently escape herbivory in their introduced ranges because local herbivores lack the evolutionary history needed to recognize or tolerate unfamiliar defenses. Whether this escape reflects phylogenetic novelty, biogeographic origin, or both remains unresolved. I used host-use data to test whether Lepidoptera richness on non-native plant genera declines with increasing phylogenetic and geographic distance from the native flora. Both predictors had negative associations with total Lepidoptera richness. Standardized coefficients were of similar magnitude for both predictors, and both effects were directionally consistent, suggesting that evolutionary proximity and biogeographic origin are each associated with herbivore richness on introduced plants. Growth form was the strongest predictor overall: woody genera supported approximately twice the Lepidoptera richness of herbaceous genera after accounting for both distance metrics and sampling effort. These results indicate that both phylogenetic and geographic distance from the native flora are associated with lower herbivore richness on introduced plants, whereas plant growth form accounts for more variation than either distance dimension alone. More broadly, the findings suggest that herbivore accumulation on non-native plants is not explained by evolutionary relatedness alone but also reflects biogeographic context and plant growth form.</p>