Dahlia cactus (Echinocereus poselgeri) belongs to Cactaceae (the Cactus family). It is an evergreen perennial herbacious plant that is distributed south Texas and northeast Mexico. This cactus grows in arid areas and grows shrubby. Stems are thin columnar, dark green, erect up to 1.2 m long, about 2 cm in diameter and have 8-10 ribs. Central spine is one, grayish white and radial spines are 9-12. Flowers are pale magenta, about 6 cm in daimeter with reddish throat in early summer.