This species has undergone a recent taxonomic change, and is now named Echinocereus arizonicus ssp. arizonicus.

The Arizona hedgehog cactus is a dark green succulent perennial plant in the Cactaceae family. Individual plants have large, robust stems that distinguish it from other species of Echinocereus. Stems range in size from 2.5 to 16 inches in height and six to ten inches in diameter. Immature plants occur as a solitary stem while mature plants are multi-branched (caespitose) with stems forming at the base, most often occurring in loose clusters of 4 to 20 stems, occasionally exceeding 50 to 100 stems (Arizona Rare Plant Committee 2001; Cedar Creek Associates, Inc. 1996). Each stem has 7 to 11 tuberculate ribs, nine to ten being the most common; ribbing strong. Spines are smooth and short; 5 to 11 radial spines per aerole (Arizona Rare Plant Committee 2001) but fewer than nine is often observed (Baker 2006). There are one to three gray or pinkish central spines that are less than 1.9 inches long, terete (smooth, cylindrical and tapering) (Zimmerman and Parfitt 2003) with the largest deflexed or bending downwards (AGFD 2003). Flowers erupt along the sides of the stem near the upper third of stem ribs, and are a brilliant crimson to deep red color. The flower is stout, erect, about 2 inches in diameter and 3 inches in length (AGFD 2003) appearing in late April to mid-May. Fruiting occurs from May to July with germination in midsummer (Zimmerman and Parfitt 2003; Arizona Rare Plant Society 2001). Fruits are red in color, globose, and spiny taking 3 months to mature (AGFD 2003). At maturity, the side of the fruit splits open (e.g., dehiscence) releasing up to 100 small black seeds (Parfitt and Christy 1992). The mechanism of seed dispersal is unknown. Its pollinators include native bees (Halictidae), honeybees (Apis mellifera), and hummingbirds (Anna's hummingbird (Calypte anna), broad-billed hummingbird Cynanthus latirostris), and black-chinned hummingbird (Archilochus alexandri) (Aslan 2015).