Plant diversity advocates say a rare cactus variety with a beautiful reddish-purple flower could be imperiled by oil and gas development in the Uinta Basin. But the Bureau of Land Management says it is protecting the plant.

Environmentalists are unhappy about the Castle Peak and Eightmile Flat Oil and Gas Expansion Project, proposed by a company called Newfield Energy.

In a petition to the U.S. Fish and Wildlife Service, they claim the federal government considers the Pariette fishhook cactus to be only a part of a larger species of cactus, and thus not rare enough to stop damage by the project.

However, the BLM field manager insists the agency will protect the Pariette fishhook, regardless of whether it is a separate species, a variety or even part of the larger species, the Uinta Basin hookless cactus.

According to the April 18 petition — filed by the Center for Native Ecosystems, Denver, and the Utah Native Plant Society, Salt Lake City — the Pariette fishhook cactus is found only on a 10-by-three-mile region in Uintah and Duchesne counties. The area has hosted oil and gas development.

The Uinta Basin hookless cactus is protected as a threatened species. The Pariette cactus actually may be a separate species or a distinct variety, say the groups, but federal officials have considered it to be part of the fishhook species. The project would "more than double" the number of wells and the amount of surface disturbance in cactus habitat, says the petition.

"The (Fish and Wildlife) Service will not be able to make a jeopardy finding regarding this project because of Uinta Basin hookless cactus' much larger geographic range and much greater abundance," the petition adds.

In other words, the groups contend that even though the hookless species is threatened, agencies think there are enough of its kind that harming some plants would not be forbidden.

However, the groups contend that the Pariette variety is not just part of the hookless species. It is a separate species or is at least a distinct taxon, they add — that is, a separate variety that retains its unique characteristics for generations.

The Fish and Wildlife Service should publish an emergency rule that the Pariette cactus is threatened or endangered and should designate critical habitat to protect it, the groups ask.

Tony Frates, a Salt Lake City man who is conservation co-chairman of the Utah Native Plant Society, said the Pariette once was considered by the Fish and Wildlife Service as part of the hookless cactus. But now scientists agree it is a separate type.