Federal and State Listed Species of Texas:
Chisos Mountains hedgehog cactus
All the populations of Chisos Mountains hedgehog cactus are found within Big Bend National Park in Brewster County in West Texas.
Chisos Mountains hedgehog cactus is a succulent perennial usually with solitary stems up to 30 cm tall and 3-5 cm wide. Stems have 10-16 vertical ridges that are divided into spine-tipped, cone-shaped projections 6-8 mm apart. Spines arising from each of these projections are numerous, but are not so dense that they hide the stem completely. Some spines (radial spines) form a ring around the projection’s tip somewhat like the spokes of a bicycle wheel. Other spines (central spines) arise interior to the radial spines and point somewhat outward and away from the stem. There are typically 10-17 thin radial spines that point up, down or sideways. The uppermost radial spines (pointing upward) are bristle-like and usually shortest at 1.6-3.2 mm long; the lowest radial spines (pointing downward) are rigid and usually longest at 6-20 mm long. Between these two groups (physically and in length) are sideways-pointing, radial spines, which are hair-like and ≤9.5mm long. As many as one to four (rarely 6) straight, central spines may be present, but frequently only one or two "main" central spines are present. These "main" central spines are more conspicuous than the other spines and point directly outward from the stem. Chisos Mountains hedgehog cactus’ pink-magenta flowers are 6-6.4 cm long and 2.5-7 cm wide. The flower’s neck is wooly and has clusters of 8-14 stiff, hair-like spines. Fruits are green to red and oval- to egg-shaped.
Although no other species is likely to be confused with Chisos Mountains hedgehog cactus within its habitat, the above set of characteristics separate this species from other nearby cacti. Specifically, the combination of individual, robust plants with a knobby stem surface, the 10-17 radial spines in three groups of different sizes, the pink-magenta flower color, and the hair-like spines of the flower’s neck create a unique set of characters found in no other cacti.
Chisos Mountains hedgehog cactus occurs amongst Chihuahuan Desert shrublands or grasslands on gravelly soils of low elevation flats and terraces within the desert basin.
Life Cycle Events
Flowering occurs from March to April and perhaps subsequently. Fruiting occurs from May to June, and perhaps into August.
Although the Chisos Mountains hedgehog cactus is visible year-round, it is most easily found while in flower in March and April.