''Cochemiea thornberi'' is a species of

cactus A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Greek ...

known by the common names Thornber's fishhook cactus and Thornber's nipple cactus. It is native to

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

in the United States and

Sonora Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign State of Sonora), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. The state is d ...

in Mexico.''Mammillaria thornberi''.
The Nature Conservancy.''Mammillaria thornberi''.
Flora of North America. This plant has numerous branches that all root in the ground, forming a clump of rooted stems all belonging to one plant. The stems are cylindrical and usually measure up to 10 centimeters tall, but known to reach 30. They are up to 3.5 centimeters wide. There are up to 21 bristle-like radial spines on each

areole In botany, areoles are small light- to dark-colored bumps on cacti out of which grow clusters of spines. Areoles are important diagnostic features of cacti, and identify them as a family distinct from other succulent plants. Gordon Rowley - W ...

and one to three hooked central spines. The flower is up to 3 centimeters wide and has white or pink inner

tepal A tepal is one of the outer parts of a flower (collectively the perianth). The term is used when these parts cannot easily be classified as either sepals or petals. This may be because the parts of the perianth are undifferentiated (i.e. of very ...

s with pink midstripes. The flowers bloom most often after heavy rainfall.''Mammillaria thornberi''.
Center for Plant Conservation. The fruit is bright red and up to 1.5 centimeters long. It is edible. It contains black seeds. This plant is associated with

nurse plants Nurse plants are plants that serve the ecological role of helping seedlings establish themselves and protecting young plants from harsh conditions. This effect is particularly well studied among plant communities in xeric environments. Effects O ...

. It often grows beneath the branches of ''

Ambrosia dumosa ''Ambrosia dumosa'', the burro-weed or white bursage, a North American species of plants in the family Asteraceae. It is a common constituent of the creosote-bush scrub community throughout the Mojave desert of California, Nevada, and Utah and ...

''. The habitat is desert scrub. There are two main population areas in Arizona, one in the

Avra Valley The Avra Valley is a 50-mile (80 km) long northwest–southeast valley, bordering the west of Tucson, Arizona. The Tucson Mountains are at the valley's center-east, with suburbs ranging east of the Tucson Mountains and trending northwest to ...

and

Saguaro National Park Saguaro National Park is an American national park in Pima County, southeastern Arizona. The park consists of two separate areas—the Tucson Mountain District (TMD) about west of the city of Tucson and the Rincon Mountain District (RMD) about ...

and one on the Tohono O'odham Indian Reservation. This species was abundant in the Avra Valley up until the 1930s until a freeze which decimated the population. There are now a total of about 600 plants in all the populations together.

References

External links

USDA Plants Profile
{{Taxonbar, from=Q1888367 thornberi Cacti of Mexico Cacti of the United States Flora of the Sonoran Deserts Flora of Arizona Flora of Sonora Least concern flora of North America Least concern flora of the United States