Pogogyne nudiuscula
Pogogyne nudiuscula is a rare species of flowering plant in the mint family known by the common name Otay mesa mint. It is native to southern San Diego County, California, where it is known only from Otay Mesa, [San Diego, California|Otay Mesa] near the border with Baja California. It was identified on land south of the Mexican border, but these occurrences have probably been extirpated. It is now known from seven vernal pool complexes just north of the border, and it is a federally listed endangered species of the United States.
This annual herb produces an erect stem in height. Its herbage is strongly aromatic and coated very thinly with straight, bristle-like hairs, or no hair. The inflorescence, wide, consists of interrupted clusters of opposite cymes. The bracts are green with acute tips. The flowers have a tube long with a bell-shaped corolla long. The corolla is purple. It flowers from March to June.
Pogogyne nudiuscula is found in coastal mesa vernal pools at elevations of on Otay Mesa, in southern San Diego County, California. It was formerly found in the vernal pools of extreme northwestern Baja California, Mexico, near the Tijuana Airport, but these populations are likely extirpated.
This plant faces a number of threats related to the loss and destruction of habitat containing its rare vernal pool ecosystem. These threats include urban development, trash dumping and pollution, vehicles, fire, grazing, and alterations in the local hydrology.