Known only from Cunningham Marsh of southern SON Co. Potentially extinct due to agriculture and development. Previously identified as P. hickmanii. See J. Bot. Res. Inst. Texas 4(1):13-18 (2010) for original description.
California Native Plant Society (CNPS).
Inventory of Rare and Endangered Plants (online edition, v8-01a).
California Native Plant Society. Sacramento, CA. Accessed on
.