RENO, Nev. (AP) — State and federal authorities are investigating the mysterious loss of a significant swath of a rare desert wildflower that's being considered for federal protection at a contentious mine site in Nevada.

The Australian mining company, Ioneer Ltd., and state biologists are investigating the unprecedented incident 200 miles southeast of Reno.

They believe small mammals most likely caused the damage to thousands of plants at the only place Tiehm's buckwheat is known to exist on earth.

Conservationists suspect a more sinister scenario.

They think somebody dug up as many as 17,000 plants while U.S. wildlife officials are considering declaring the plant endangered.