Opuntia basilaris var. heilii S.L.Welsh & E.Neese
Notes: See http://www.unps.org/segolily/Sego2012MayJun.pdf
Family: Cactaceae
Heil's beavertail
Opuntia basilaris var. heilii image
Welsh, S. L., Atwood, N. D., Goodrich, S., & Higgins, L. C. (1993). A Utah flora (No. Ed. 5). Brigham Young University.

Joints mainly obovate to spatulate, green or suffused with blue or purple; glochids tan to yellowish.

Salt desert shrub communities at 1460 to 1680 m in Emery, and Wayne cos.; a Navajo Basin endemic; 8 (i).

[Type: Utah, Wayne Co., sw. of Hanksville, Elizabeth Neese 5938,1 Jul 1978, holotype BRY!] 

Confused with O. basilaris var. longiareolata which in Utah occurs along the Colorado drainage system in Garfield, Kane and San Juan Cos.  Var. heilii grows in a colder environment, with more open terrain, and different parent rocks and soil. It also differs from var. longiareolata in having paler flowers, generally wider pads without elongated narrow pad bases, yellow glochids instead of yellow-brown, few or no trichomes papillae)on the pads, mature pads that are not glaucous epidermis, a somewhat less tightly clustered habit, and more widely spaced areoles (4 to 6 rather than 6 to 9 at midstem), and tending to lay flatter in winter becoming procumbent/prostrate.