The Collaborative International Dictionary of English v.0.48:
Pholistoma \Pholistoma\ prop. n. A genus of straggling herbs of the southwestern U.S. Syn: genus Pholistoma. [WordNet 1.5]WordNet (r) 3.0 (2006):
Pholistoma n 1: straggling herbs of southwestern United States [syn: Pholistoma, genus Pholistoma]