Huastecacris alexandri n. sp., is described from the El Cielo Biosphere Reserve in southern Tamaulipas, northeastern México. Geographic distribution is limited to the highlands of the reserve where it occurs from 1300 to 1700 m in open areas on natural, low vegetation. This species is most related to Huastecacris zenoni Fontana & Buzzetti 2007, which is found in the lowlands of the reserve, extending the distribution of the genus along the Eastern Sierra Madre up to Cd. Victoria's mountain range. The species are distinguished by details of the male cerci, supra-anal plate, genitalia and color pattern.