Deamia montalvoae is a species of flowering plant in the family Cactaceae, native to southeastern Mexico, Guatemala and El Salvador.

[2][3] It climbs or hangs from trees or rocks, and has large funnel-shaped flowers, mostly white, and pale red fruit, covered with bristles and hairs.

All three populations shared similar characteristics, but seemed to differ from known species in some respects, such as having much longer flowers than expected for D. chontalensis.

The specific epithet honours Edy Albertina Montalvo, a pioneering El Salvadorian woman botanist.

[3] Deamia montalvoae occurs in three known and isolated populations: Chiapas in the Sierra Madre del Sur mountains in Mexico, Huehuetenango in Guatemala, and Santa Ana in El Salvador.