Known variously as foxtail cactus, pincushion cactus or spiny star, escobaria is another group of small, tubercular cacti, similar to mammillaria and coryphantha; the main difference with the former is that flowers appear at or near the top rather than lower down the stem, while the latter has different seeds (the surface is crossed rather than pitted). The US has over a dozen escobaria species, most very localized and uncommon, the main exceptions being pink-flowered escobaria vivipara and yellow-flowered escobaria missouriensis, which are widespread across half of America. Most form low clumps, with stems covered by a dense network of short, pale-colored spines. All escobaria species are alternatively classed as coryphantha.


The other US species are:

Escobaria albicolumnaria, column foxtail cactus, Big Bend area of west Texas (rare)
Escobaria duncanii, Duncan's foxtail cactus, west Texas (rare)
Escobaria emskoetteriana, or escobaria pottsiana, junior tom thumb cactus, along the Rio Grande in south Texas
Escobaria guadalupensis, Guadalupe Mountain foxtail cactus, in the Guadalupe Mountains of west Texas (rare)
Escobaria minima, Nellie beehive cactus, vicinity of Marathon in far west Texas (rare)
Escobaria missouriensis, Missouri foxtail cactus, from Arizona to Louisiana and north to the Canadian border
Escobaria orcuttii, Orcutt's foxtail cactus, southwest New Mexico
Escobaria organensis, Organ Mountain foxtail cactus, Organ Mountains of south New Mexico (rare)
Escobaria robbinsiorum, Cochise foxtail cactus, mountains of far southeast Arizona (rare)
Escobaria sandbergii, San Andres Mountain foxtail cactus, San Andres Mountains of south New Mexico (rare)
Escobaria villardii, Sacramento Mountain foxtail cactus, Sacramento Mountains of south New Mexico (rare)