Woodsia phillipsii
Woodsia phillipsii Windham
(for Walter S. Phillips, 1905–1975, collector of the type specimen, “a pioneer in the study of Arizona ferns” [Windham 1993e], and author of A Checklist of Arizona Ferns, 1946, 1947; see Mason [1975] for epitaph)
Local names: Phillips’ cliff fern
Leaves to 35 cm long, usually smaller, the blades lanceolate, 2-pinnate-pinnatifid, usually 2-pinnate proximally, occasionally forked at tip, sparsely glandular, the vein tips usually enlarged to form whitish hydathodes visible on the lower surface of the pinnules; indusia with segments divided into narrow, thread-like filaments nearly to the base; spores 37–44 μm, 2n = 76 (diploid) (Windham 1993d). Cliffs and rocky slopes usually in crevices, typically on igneous substrates; in the Trans- Pecos in Brewster (e.g., Correll 13681, BRIT, TEX-LL, both annotated by M.D. Windham), Jeff Davis (Warnock 23027, TEX-LL), Presidio (Yarborough & Powell 2002), and Culberson (Turner et al. 2003) cos.; AZ, NM, TX, also n Mexico. Sporulating summer–fall. This species was only relatively recently recognized as distinct (Windham 1993e). In the past it and W. neomexicana were both often identified as W. mexicana (e.g., Correll 1956), a related species not known in the U.S. Woodsia phillipsii sometimes hybridizes with the related and morphologically similar tetraploid W. neomexicana to form sterile triploids; it can also hybridize with W. plummerae (Windham 1993d). Because of its limited distribution in the state, we consider this species to be of conservation concern in TX.