Curved Dry Rock Moss - Grimmia incurva
Curved Black Rock Moss
Plant: Rounded cushions. Green to black-green. Stems 1.0-2.0 cm tall. Stem X-S with a central strand.
Leaf: When dry, leaves are incurved and mildly contorted. When moist, leaves spread. Oblong to linear-lanceolate, 2.5-4.5 x 0.3-0.5 mm, keeled, and tapers to a slender and acuminate apex that is often hyaline. Awn short and often mucronate (use hand-lens). Both margins plane or one/both sides recurved proximally. Costa ends before apex and projects on abaxial side (keeled).
Leaf Cells: Basal laminal cells near costa are long-rectangular, slightly sinuose, thick-walled. Basal laminal cells near margin are short- to long-rectangular and thin-walled. Median laminal cells are rectangular, nodulose, and thick-walled. X-S: distal laminal cells are 1-layered except margins and apex are 2-layered. Costa X-S: distally semi-circular in outline (keeled).
Its distinctive characteristics include dark, round cushions with linear, contorted leaves in shaded, sub-alpine habitats. The awns are noticeable only with a hand-lens. Its habit is similar to Dicranowesia crispula.
Greenland; Canada: AB, BC, NB, NL, YT; USA: CA, CO, ME, NH, NY, OR, SD, WA; Eurasia (FNA 2007). In Montana: Flathead and Ravalli Counties (Elliott 2016).
Observations in Montana Natural Heritage Program Database
Number of Observations:
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Map Help and Descriptions
(Observations spanning multiple months or years are excluded from time charts)
Shaded, damp acidic rock. Moderate to high elevations (1,640 – 8,200 feet). It prefers shaded microsites in the sub-alpine. It is uncommon in the continental interior.
Dioicous. Seta is 1.5-2.0 mm tall, arcuate, and asymmetrically attached to base of capsule. Capsules are occasionally found, emergent to exserted, yellowish, smooth or little wrinkled when dry, oblong-ovoid to cylindric.
Gemmae absent on leaves.
- Literature Cited AboveLegend: View Online Publication
- Elliott, J.C. and A.K. Pipp. 2018. A Checklist of Montana Mosses (1880-2018). December 20th. Montana Natural Heritage Program, Helena, Montana. 73 pp.
- Flora of North America Editorial Committee, eds. 2007. Flora of North America North of Mexico. Volume 27. Bryophytes: Mosses, Part 1. Oxford University Press, Inc., NY. xxi + 713 pp.
- Additional ReferencesLegend: View Online Publication
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- Lawton, E. 1971. Keys for the Identification of the Mosses on the Pacific Northwest. Reprinted from 'Moss Flora of the Pacific Northwest'. Published as Supplement No. 2 of the Journal of the Hattori Botanical Laboratory. Nichinan, Miyazaki, Japan. 66 pp.
- Lawton, E. 1971. Moss Flora of the Pacific Northwest. Hattori Botanical Laboratory. Japan: Yamabuki-cho, Shinjuku-ku, Tokyo. 362 pages plus appendices.