Abstract
A new species, Russelia tehuana (Plantaginaceae), is described from the Sierra Madre del Sur in the southern part of Oaxaca, Mexico. This taxon is distinguished from all other Russelia species by the hirsute pubescence, the resinous lepidotes present on both leaf surfaces, the small flowers and the centrally narrow corolla tube. Here we describe and illustrate this species, discuss its known distribution, and compare it with other Russelia species that grow in the state of Oaxaca.