Orthotrichum hutchinsiae Smith
Plants 0.4--4 cm. Stem leaves erect-appresssed, stiff, ± slightly curled or twisted around stem, never contorted or crisped when dry, narrowly lanceolate-oblong to lanceolate, broadly acute, to obtuse, 1.4--2.2 mm, leaf base not much differentiated to broad, oblong; margin ±recurved to near apex, distal laminal cells 7--14 µm wide, with small to large, conic to clavate papillae; basal laminal cells rectangular to elongate-rectangular, ± nodose, thick-walled. Sexual condition autoicous. Seta 2.5--3.5 mm. Capsule oblong-elliptic to cylindric-fusiform, 1.1--2 mm, slightly to moderately 8-ribbed 1/3--1/2 length; stomates numerous in neck; peristome double; endostome segments 8, papillose-striate; exostome teeth 8, rarely splitting to 16, reflexed, densely papillose, perforate near tips. Calyptra oblong-conic, very hairy. Spores 9--16 µm.
Varieties 2 (2 in the flora): e and n North America; Europe; Asia.
The species is continuously distributed in eastern North America from Newfoundland and northern Quebec west to western Ontario and south to Georgia and Alabama, and is disjunct in western Arkansas and eastern Oklahoma, the Black Hills of South Dakota, eastern Arizona, and southeastern Alaska. It is distinguished by erect, non-crisped leaves; cylindric, fully exserted capsules slightly smaller at the mouth and poorly differentiated marginal basal cells. Ulota hutchinsiae resembles species of Orthotrichum, especially O. anomalum. That species occurs on calcareous substrates and has capsules with immersed stomates and eight long and eight short capsule ribs. Ulota curvifolia, another rock-growing species is more northern in distribution and has somewhat twisted and curved leaves.
