SPECIES FACT SHEET
Common Name: Forest brownwort, larger cut notchwort (Edwards 2003)
Scientific Name: Tritomaria exsectiformis (Breidl.) Loeske
Division: Marchantiophyta (incorrectly called Hepatophyta in U.S. government
taxon databases (e.g., ITIS 2008); see Stotler and Crandall-Stotler 2008)
Class: Jungermanniopsida
Order: Jungermanniales
Family: Jungermanniaceae
Technical Description: Small, yellowish green to brownish green plants with
two rows of asymmetrical leaves, growing in small tufts among other liverworts
and mosses. Shoots to 3 cm long and 1.5–2 mm wide, ascending, green to
brownish, sparingly branched. Rhizoids colorless to brownish. Leaves
succubous, contiguous to imbricate, channeled, 2-3 lobed with the dorsal lobe
slender, divergent, and usually positioned only 2/3 up the margin. Cells with
thin walls and bulging trigones, cuticle usually strongly verruculose. Oilbodies in median cells 3–6 per cell (Arnell 1981), 5–12 per cell (Hong 2002), 7–
13 per cell (Damsholt 2002), 12–15 per cell (Schuster 1969), or 8–16 per cell
(Paton 1999). Oregon material seems to fit into the 5–13 oil-body per cell range
(Wagner, pers. obs.). Reddish brown, angular, 2-celled gemmae in globular
masses are frequent at the tips of the leaf lobes. The gemmae masses are most
prominent at the shoot tips. Underleaves lacking. Reproductive structures are
rare; according to Schuster (1969), plants are usually sterile.
Distinctive Characters: The asymmetrical, 2-3 lobed leaves which are
transversely inserted distinguish the genus and the brownish, angular gemmae
distinguish the species.
Similar species: Very similar to T. exsecta. Tritomaria exsectiformis has
angular gemmae while T. exsecta has smooth, ovoid gemmae, T. exsectiformis
usually has thin cell walls with bulging trigones while T. exsecta has nearly
evenly thickened cell walls.
Life History: Published studies of life history traits in this particular species
have not been located. This species is perennial, visible whenever the substrate
is exposed. These plants are mostly found at high elevations where snow lies
late, generally above 5000'/1500 m, and thus will have a short season that
coincides with late summer and fall. Reproduction is entirely vegetative,
primarily by dispersal of gemmae.
Range, Distribution, and Abundance: Tritomaria exsectiformis is an arcticalpine, circumboreal species that is missing in Eastern Asia. Within Western
North America it is known from Alaska, British Columbia, Colorado, Idaho,
Montana, Oregon, Washington and Wyoming (Harpel and Dewey 2005). The
species is sporadically distributed in northern parts of its range; it is reported
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abundant in the Great Lakes region (Schuster 1969). In the Pacific Northwest it
appears to be quite rare.
The Oregon Natural Heritage Information Center (ORNHIC 2007) lists sites in
Deschutes, Douglas, Jefferson and Klamath Counties.
Hong (1994) cites no specimens but maps a single locality in Washington; the
dot on his map is in the general vicinity of Wenatchee but the record on which
the mapping is based is probably located in the Cascade Mountains further to
the west.
"Recently a new site was located on the Olympic National Forest, (Clallam Co.)
near Sequim, Washington. In eastern Washington there are sites on the
Okanogan-Wenatchee National Forest (Okanogan County) and on the Colville
National Forest (Stevens County)." Harpel and Dewey (2005).
BLM: Suspected in Klamath Falls Resource Area.
USFS: In Oregon documented in Deschutes, Umpqua and Willamette
National Forests; suspected in Fremont-Winema, Mt. Hood and Rogue
River-Siskiyou National Forests. In Washington documented in
Okanogan-Wenatchee and Colville National Forests; suspected in Mt.
Baker-Snoqualmie and Gifford Pinchot National Forests.
Habitat Associations: On peaty or humic soil, or rotting wood, often on creek
banks where perpetually shady, cool, and moist. Cold water springs with a
substantial flow are likely spots, in mixed coniferous forests above 3,000'
elevation on the east slope of the Cascade Mountains. Associates may include
Lophozia incisa, L. ventricosa, Blepharostoma trichophyllum, Calypogeia
muelleriana, Cephalozia lunulifolia, and Lepidozia reptans.
"Within the Pacific Northwest this species is currently known from midelevational (3200-5200 feet) riparian zones. Typically, its habitat is open to
shaded coniferous forest in association with low volume, perennial water flow
at or near springs and seeps, along very gentle topographic gradients.
Lodgepole pine (Pinus contorta) is present at nearly all sites of T. exsectiformis
within the Oregon and Washington Cascades. Other tree species occurring at
these sites include white fir, ponderosa pine, Engelmann spruce (Picea
engelmannii), Douglas fir (Pseudotsuga menziesii), western hemlock (Tusga
heterophylla), mountain hemlock (Tusga mertensiana), and subalpine fir (Abies
lasiocarpa). Currently, all but one of the T. exsectiformis sites in the Oregon
and Washington Cascades occur within spring-fed hydrologic systems." Harpel
and Dewey (2005).
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Threats: The proximity to streams, campgrounds and trails poses threats from
incidental recreational damage. Other resource use, such as water source
development, logging, grazing, or special forest products, that causes
degradation of substrate or change in hydrologic status could threaten
persistence of healthy populations.
Conservation Considerations: A thorough Conservation Assessment
document has been prepared by Harpel and Dewey (2005), which discusses
conservation status and potential management approaches. This species
occurs in habitats with a high potential for conflicts between management
activities and habitat protection. Monitor known sites and consider
management need when habitat changing activities are proposed in the vicinity
of sites.
Conservation Rankings and Status:
Global: G5; Oregon: S2
ORNHIC List 2
Washington: Not ranked
BLM/USFS Sensitive in Oregon
Other pertinent information:
Surveys and Survey Protocol: Search stream banks and riparian zone
immediately below cold water springs with steady water flow in upper montane
regions.
Key to Identification of the Species: Christy and Wagner 1996.
Preparer: David H. Wagner
Edited by: Rob Huff
Date Completed: October, 2008
References:
Arnell, S. 1981. Illustrated Moss Flora of Fennoscandia. I. Hepaticae.
2nd. Edition. Swedish Natural Science Research Council.
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.
Damsholt, K. 2002. Illustrated Flora of Nordic Liverworts and Hornworts.
Nordic Bryological Society, Lund, Sweden.
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Edwards, S.R. 2003. English Names for British Bryophytes. Third Edition.
British Bryological Society Special Volume No. 5.
Harpel, J.A. and R. Dewey. 2005. Conservation Assessment for Tritomaria
exsectiformis (Breidl.) Schiffn. Unpublished report prepared for USDA
Forest Service Region 6 and USDI Bureau of Land Management, Oregon
and Washington.
Hong, W.S. 2002. Tritomaria. Bryophyte Flora of North America, Provisional
Publication, Missouri Botanical Garden.
http://www.mobot.org/plantscience/BFNA/v3/JungTritomaria.htm
Accessed: August 2008.
ITIS. 2008. Integrated Taxonomic Information System (official government
database of scientific names) http://www.itis.gov/index.html Accessed
June 2008.
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
Paton, J.A. 1999. The liverwort flora of the British Isles. Harley Books,
Colchester, U.K.
Schuster, R.M. 1969. The Hepaticae and Anthocerotae of North America.
Volume 2. Columbia University Press, New York.
Stotler, R.E. and B. Crandall-Stotler. 2008. Correct author citations for some
upper rank names of liverworts (Marchantiophyta). Taxon 57: 289-292.
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