SPECIES FACT SHEET Common Name: Narrow-fruited crisp-moss
Scientific Name:Oxystegus tenuirostris (Hook. & Taylor) A.J.E. Sm.
Taxonomic Note: There has been confusion over the appropriate scientific name for this species. Although the Oregon Natural Heritage Information Center and NatureServe Explorer use the name Oxystegustenuirostris, the appropriate name for this species is Trichostomum tenuirostre. With the exception of Zander’s treatment in The Moss Flora of Mexico, (Sharp et al 1994) all of the current literature treats this species as T. tenuirostre. Because the current ITIS and USDA Plants databases currently do not recognize Trichostomum tenuirostre as a valid name, we have continued to use Oxystegus tenuirostris for this fact sheet.
Technical Description: Plants in yellow to brownish loose or dense tufts, up to 3 cm tall; leaves twisted when dry, oblong-lanceolate to narrowly linear-lanceolate, apex acute, apiculate, ± 1–3 coarse teeth, fragile, often broken or torn; costa glossy, prominent, ending in the apex; margins plane, wavy or undulate, entire, ± marginal papillae; upper median cells 7–10 µm, quadrate to irregularly isodiametric, thick walled, 3–8 small papillae per cell; basal cells shortly rectangular to elongate-oblong, hyaline to reddish, smooth, not extending up the margins. Dioicous; seta 7–11 mm long, capsules cylindric, 1.2–1.6 mm long, peristome teeth irregularly bifid, ± papillose.
Distinctive characters: (1) the brittle, wavy, undulate leaves (2) plane leaf margins (3) lack of hyaline basal cells extending up the margins.
Similar species:Didymodon vinealis, Weissia spp. and Tortella spp. can be separated from T. tenuirostre on the above distinctive characteristics.
Other descriptions and illustrations: Crum & Anderson 1981; Flowers 1973; Lawton 1971; Sharp et al 1994.
Life History: Specific details for this species are not documented. In general the protonema, spore germination and development are typical of all mosses. According to Schofield (1976) and Flowers (1973) sporophytes are rarely found in this species which could be contributing to the rarity of this species.
Range, Distribution, and Abundance:Trichostomum tenuirostre is known from Central and South America, Artic, Eurasia, Africa, Indian Ocean Islands, Hawaii, New Zealand, Australia and eastern North America. In the Pacific Northwestern North America Trichostomum tenuirostre is found in Alaska, Alberta, British Columbia, Washington, Oregon, Montana, California, Colorado, and Arizona.
Oregon Natural Heritage Information Center reports it from Clackamas, Jackson and Lane Counties in the Klamath Mountain and west Cascade Ecoregions.
BLM: Suspected on Eugene and Medford Districts.
and on the Columbia River Gorge National Scenic Area.
Suspected on Rouge River-Siskiyou National Forests, and
Siuslaw National Forest.
Other: Documented from the Olympic Peninsula
Habitat Associations:Trichostomum tenuirostre occurs on damp to moist soil, soil over rock, peaty banks, humid cliffs, rarely on tree bases and logs that may be occasionally flooded. Label data includes: shaded cliff crevice, on dry sandstone crevices, on wet granite by brooklet, on bolder by stream. It appears that this species needs damp or wet shaded sites. In British Columbia according to Schofield (1976) T.tenuirostre occurs from near sea-level to subalpine elevations. Lawton (1971) comments that it is found in the lowlands up to 3000 m and rarely to 4500 m. elevation.
Threats: Changes in hydrology could pose a threat to this species. Road, trail construction or quarrying at known sites may also be a threat. Logging in areas of known populations could change the lighting which could alter populations.
Conservation Considerations: Known localities could be revisited to determine the extent of the populations and characterize habitats. It would be good to explore similar habitat to find new populations.
Conservation Rankings and Status:
Global: G4, Oregon (S1), Montana (SH)
Oregon: ORNHIC List 3
Washington: Not ranked
BLM/USFS Strategic Species in Oregon
Preparer: Judith A. Harpel Ph.D.
Date Completed: November 2008
Edited by: Rob Huff, March 2009
References: Crum, H. & L. Anderson. 1981. Mosses of Eastern North America. 2
volumes. Columbia University Press, New York. 1328 pp.
Flowers, S. 1973. Mosses: Utah and the West. Brigham Young
University Press. Provo, UT. 567 pp.
Lawton. E. 1971. Moss Flora of the Pacific Northwest. The Hattori
Botanical Laboratory. Nichinan, Miyazaki, Japan. 362 pp.
NatureServe Explorer. 2008. An Online Encyclopedia of Life. http://www.natureserve.org/explorer/ Schofield, W.B. 1976. Bryophytes of British Columbia III: habitat and
distributional information for selected mosses. Syesis 9: 317 –
Sharp, A., & H. Crum, P. Eckle. 1994. The Moss Flora of Mexico.
Memoirs of the New York Botanical Garden. Vol. 69 part 1
Sphagnales to Bryales. New York Botanical Garden Press. Bronx.