Opuntia basilaris Englem. & Bigelow var. heilii S.L. Welsh & Neese. Named in honor of botanist Ken Heil.March 22, 2009, Goblin Valley State Park, Emery County, Utah, elevation here about 4,970 ft. This was the only plant found in this vicinity, and this location is at the northeastern end of its range. Growing here seemingly in Entrada Sandstone derived soil but more typically found in sandy clays of the Mancos Shale formation, or powdery silty sands of the Curtis Formation.Described in 1983, a restricted Utah endemic occurring only in southern Emery and Wayne (its primary distribution) Cos. limited to and occurring intermittently within an area about 25 miles wide and 30 miles long. It does NOT occur in Garfield Co. based on present knowledge and contrary to the inclusion of that county in the Utah Flora series through the 4th edition (2008).Included as a synonym in FNA Vol. 4:145. 2003, and Pinkava (2003) under O. basilaris var. longiareolata but referred to incorrectly there as O. heilii Welsh & Neese (it was in fact published as a variety of O. basilaris in GBN, 43(4):700. 1983). The closest this taxon comes to O. basilaris var. longiareolata which is rare in Utah and found essentially in only one river gorge location is about 35 miles away from the most southwestern point of O. basilaris var. heilii.This does appear to be a distinctive entity worthy of recognition; in fact, it should perhaps be recognized at the species level for a number of reasons. Its habit/growth form is different. It solely grows in a very isolated, disjunct area that is higher elevation, and that encounters extreme temperature ranges and survives in very cold weather, and grows in sandy habitats of high salinity. Its pads lack trichomes compared to "normal" O. basilaris. The shape, color, thickness etc. of the pads are very different at all times of the year. Flowers are more pale than other varieties. The size/shape of the areoles are different, the glochids appear to be different, and the areoles are spread about and appear to fairly consistently fall into the range of (4) 5-6 (8) at mid-stem which puts them at the extreme low end for the species and very different from var. longiareolata which normally has pads with trichomes that are mainly spathulate and darker flowers and a different growing habit and which grows in lower elevations and in different habitats that mainly follow river drainages. It may in fact be the most unique species in the Basilares group.