Flora of North America species comparison

In North America, Grimmia trichophylla is principally a lowland species, occurring in the mountains up to about 1000 m., rarely higher. In the Southern Hemisphere, it may be found up to 4000 m. In New Zealand, the species is common, and in contrast to G. trichophylla in North America, frequently bears capsules. The New Zealand plants are usually smaller than American specimens, and the leaves are frequently contorted. The nearly cosmopolitan G. trichophylla has many phenotypes, and numerous subspecies and varieties have been described. In damp and shaded habitats, the awns may be short, just as in dry unfavorable habitats at high altitudes, where stunted specimens may occur with small, short leaves and reduced awns, or even with muticous leaves. Grimmia trichophylla has frequently been confused with related species such as 36. G. muehlenbeckii and 34. G. lisae (see discussions thereunder for identification details). Robust forms of G. trichophylla have been mistaken for G. austrofunalis (H. C. Greven 1997, 2003), which does not occur in North America. Although some of those plants have leaves of equal length along the stem, characteristic of G. austrofunalis, they also have both leaf margins recurved, and the medial and outer basal laminal cells are longer and more robust than in that species.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Of conservation concern.

Grimmia lesherae is apparently endemic to the high mountains along the Pacific Coast of western North America. At present, it is known only from a few damp high elevation sites in Washington and northern California, but suitable habitats exist all along the high coastal mountains and so it may also be expected in Oregon. It is a distinctive species that is unlikely to be confused with others. There are some similarities to G. incurva, but that species has short hair-points, the leaves are linear, the medial cells have nodulose walls, and the seta is arcuate. The combination of keeled leaves with recurved margins, and straight seta is unique in the subgenus. Grimmia lesherae appears to be intermediate between subg. Guembelia and subg. Rhabdogrimmia, calling into question the division of the genus into four subgenera. A peculiar distinguishing character is the left-handed twist of dried-up setae, unique in the genus. K. G. Limpricht ([1885–]1890–1893, vol. 1) incorrectly reported the left-hand twisted, dried up setae as common in Grimmia.

(Discussion copyrighted by Flora of North America; reprinted with permission.)