SPECIES FACT SHEET
Common Name: Ribbed mountain moss, helmet moss, conostomum
moss
Scientific Name: Conostomum tetragonum
Division: Bryophyta
Class: Bryopsida
Order: Bryales
Family: Bartramiaceae
Technical Description: Plants erect, 2-10 (50) mm tall, about 0.5 mm
wide, bright green or bluish-green with tinges of copper color. Leaves 0.81.5 mm long, strongly keeled, tightly imbricate, usually with a small
yellow or copper-colored and papillose awn. The distal ends of the leaf
cells are usually papillose. The leaves are usually arranged in five
distinct longitudinal rows or ranks extending the length of the shoots,
the rows straight or spiraled, giving the plants a distinctive grooved
appearance. The lower shoots are often densely clothed in brownish-red
rhizoids. Setae yellowish, 8-25 m long. Capsules ovoid, 2-2.5 mm long
and looking like shriveled apples, but they are infrequent in the Pacific
Northwest. Distinctive characters: (1) Narrow, erect shoots with closely
imbricate leaves in five distinct rows, (2) dense brown rhizoids below, (3)
bluish-green color and (4) high-altitude habitats. Similar species:
Bartramia ithyphylla, Philonotis fontana and Aulacomnium palustre all
have a green or bluish-green color and abundant brown rhizoids.
Philonotis and Aulacomnium grow on seepy, wet soil or peat, and
Bartramia grows in drier crevices and ledges of rocks and cliffs. All three
species have spreading leaves that are not arranged in longitudinal rows,
and in all other characters they are larger plants. Other descriptions
and illustrations: Flowers 1935: 154; Nyholm 1960: 293; Lawton 1971:
209; Crum and Anderson 1981: 641; Vitt et al. 1988: 80; Christy and
Wagner 1996: VII-24; Griffin 2003; Hodgetts 2007.
Life History: Details for Conostomum are not documented. The
protonema is inconspicuous, forming buds and shoots in usual fashion
of moss growth and development.
Range, Distribution, and Abundance: Circumboreal. In the Pacific
Northwest, known from British Columbia, Montana, Washington,
Oregon, and California.
1
National Forests: documented from Mt. Hood NF (Christy et al. 1980);
suspected from all forests in Oregon and Washington with alpine and
subalpine habitats. Documented from Olympic National Park (Hutten et
al. 2005). BLM Districts: none documented and none suspected because
of lack of suitable habitat.
Rare in the Pacific Northwest but probably undercollected.
Habitat Associations: Occurring as small sods or inconspicuous
individual shoots intermixed with other bryophytes, on soil in rock
crevices in boulder fields, moraines, and ledges of cliffs. Subalpine to
alpine elevations, often in areas of late snowmelt. On Oregon's Mt. Hood
Conostomum occurs above timberline at about 6,500 ft, where the plant
association is probably Phyllodoce empetriformis and Cassiope
mertensiana heath. Elsewhere in the Pacific Northwest Conostomum
probably also occurs in Pinus albicaulis, Tsuga mertensiana, Abies
lasiocarpa, and Abies amabilis associations.
Threats: Habitats in the Pacific Northwest are usually remote and visited
by few people. Rock climbing, trail construction, trail maintenance, and
hiking may impact Conostomum locally but not over large areas of
subalpine and alpine habitat. However, air pollution and climate change
are serious long-term threats. Species growing on peaks and ridgetops
are subject to accumulation of aerosols from cloud interception. Longterm air quality monitoring could identify possible threats and impacts.
Conostomum is one of a suite of bryophytes restricted to alpine and
subalpine habitats in the Pacific Northwest, and populations south of the
Canadian border may be at risk because of rising temperatures and loss
of alpine habitat.
Conservation Considerations: Revisit known localities and monitor the
status of the populations. Search for new populations on federal lands.
Protection of known sites from recreational activities, particularly alpine
hiking and rock climbing, will minimize risk to populations.
Conservation rankings: Global: G5; National: NNR. British Columbia:
S3S5; Oregon: S1, List 2; Washington: S1, Working List.
Preparer: John A. Christy
Date Completed: June 2007
Edited by: Rob Huff, July 2007
2
Revised by Lara Drizd, November 2012
(Revision only adds Attachment 1, Photos).
ATTACHMENTS:
(1)
Photos
References
Christy, J.A. & D.H. Wagner. 1996. Guide for the identification of rare,
threatened or sensitive bryophytes in the range of the northern
spotted owl, western Washington, western Oregon and northwestern
California. USDI Bureau of Land Management, Oregon-Washington
State Office, Portland. 222 pp.
Christy, J.A., J.H. Lyford & D.H. Wagner. 1982. Checklist of Oregon
mosses. Bryologist 85: 22-36.
Crum, H. & L.E. Anderson. 1981. Mosses of Eastern North America. 2
vols. Columbia University Press, New York. 1328 pp.
Flowers, S. 1935. Family Bartramiaceae. Pp. 152-180 in: Grout, A.J.
Moss Flora of North America North of Mexico. Vol. 2. Published by the
author. Newfane, Vermont.
Griffin, D. 2003. Bartramiaceae—Conostomum. Version 1. Bryophyte
Flora of North America, Provisional Publication, Missouri Botanical
Garden.
http://www.mobot.org/plantscience/bfna/v2/BartConostomum.htm
Hodgetts, N. 2007. Conostomum tetragonum. In: British mosses and
liverworts, a field guide. Provisional Publication, British Bryological
Society.
http://www.bryosoft.co.uk/fieldguide/accounts/mosses/Conostomu
m tetragonum_MPT.pdf
Hutten, M., A. Woodward & K. Hutten. 2005. Inventory of the mosses,
liverworts, hornworts, and lichens of Olympic National Park,
Washington: species list. U.S. Geological Survey, Scientific
Investigations Report 2005-5240. 78 pp.
3
Lawton, E. 1971. Moss Flora of the Pacific Northwest. Hattori Botanical
Laboratory, Nichinan, Japan. 362 pp.
Norris, D.H. & J.R. Shevock. 2004. Contributions toward a bryoflora of
California: I. A specimen-based catalogue of mosses. Madroño 51: 1131.
Nyholm, E. 1954-1969. Illustrated Moss Flora of Fennoscandia. Vol. 2.
Musci. CWK Gleerup, Lund, and Natural Science Research Council,
Stockholm. 799 pp.
Oregon Natural Heritage Information Center. 2007. Rare, threatened and
endangered species of Oregon. Oregon Natural Heritage Information
Center, Oregon State University. Portland. 100 pp.
http://oregonstate.edu/ornhic/2007_t&e_book.pdf
Vitt, D.H., J.E. Marsh & R.B. Bovey. 1988. Mosses, Lichens & Ferns of
Northwest North America. University of Washington Press, Seattle. 296
pp.
Washington Natural Heritage Program. 2005. Working list of mosses.
Washington Department of Natural Resources, Olympia.
http://www.stage.dnr.wa.gov/nhp/refdesk/lists/mosses.html
4
Attachment 1 – Photos
All photos by J. Harpel, under contract with the Oregon/Washington Bureau of Land
Management.
Whole dry mount
5
Whole leaf
Leaf apex
Alar and basal cells
Upper medial cells
6
Sporophyte wet
Peristome teeth dry
Peristome teeth close up
Fused peristome
7
Whole mount wet
Perigonum
Perichaetium
8