SPECIES FACT SHEET
Common Name: Pleated earwort
Scientific Name: Diplophyllum plicatum Lindb.
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: Scapaniaceae
Taxonomic note: Diplophyllum plicatum is placed in the genus Scapania by
Potemkin (1999).
Technical Description: Relatively large plants, averaging 3.5–4 mm wide and
2–3 cm long when normally developed. The stems are little branched, forming a
turf-like cushion on the substrate. Leaves in two rows, deeply bilobed, with the
lobes folded and clasping the stem (complicate-bilobed). Underleaves lacking.
Lobes of unequal size but similar shape, broadly lingulate, rounded at the
apices, the dorsal lobe about one-third the length of the ventral lobe. Fold of
the lobes keeled. Lobe margins finely denticulate. There is a well developed
band of elongated cells (called a vitta) running down the center of each lobe
from base to mid lobe. The median cells are large, greater than 20 µm wide;
trigones are coarsely nodose. Gemmae cubic, with rounded edges (Doyle and
Stotler 2006), not seen in regional material. Dioicous, with a perianth that is
plicate and narrowed to the mouth; reproductive structures not known from
Oregon material.
Distinctive Characters: A large species with two rows of bilobed leaves. The
lobes are long, angled away from the stem, and folded over each other. The
upper, dorsal lobe is the smaller one. Fold of the leaf lobes is keeled, unlike
other species of the genus. In the field the decurrent, dentate, wine red ventral
leaf base is distinctive; to the naked eye it looks like a wavy red line running
down the underside of the stem just below the apex.
Similar species: This species stands out from its most common associate,
Scapania bolanderi, by its pale green color and fine marginal dentition. The
much more common Diplophyllum albicans has a vitta which is more
prominent than that of Diplophyllum plicatum , easily seen in the field with a
hand lens. Diplophyllum albicans is usually found on soil. Plagiochila
porelloides may be found growing with D. plicatum. It is about the same size
and often similar color. In the field the long decurrent, red toothed ventral lobe
will distinguish D. plicatum from any look alike.
Life History: This species is perennial, visible whenever the substrate is
exposed. Published studies of life history traits in this particular species have
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not been located. Most perennial liverworts have an active growing season that
matches the rainy season of low elevations: October through May.
Range, Distribution, and Abundance: A north Pacific species found along the
western coast of North America, from California north to British Columbia, and
Alaska through the Aleutians to Japan (Schofield et al., 2005). Strictly coastal
in the southern part of the range. Relatively common in British Columbia and
Washington, becoming scarce in Oregon and with a single record from
California (Doyle and Stotler 2006).
Oregon Natural Heritage Information Center lists the species as occurring in
Clatsop, Coos, Douglas, Lane, Lincoln, and Tillamook Counties in Oregon.
Reported from 18 localities on the Olympic Peninsula, Washington, counties
unspecified (Hutten et al. 2005). Also known from Snohomish County,
Washington (specimen in herbarium at Oregon State University).
BLM: Documented in Coos Bay District. Suspected in Eugene, Salem,
and Roseburg Districts.
USFS: Documented in Siuslaw N.F. Suspected in Rogue River-Siskiyou
National Forest. Suspected in all national forests covering the Olympic
Mountains or the Cascade Mountains in Washington.
Habitat Associations: Primarily on conifers, especially Picea sitchensis, but
also on hardwoods such as Alnus rubra. The California record is from Sequoia
sempervirens. Usually growing intermixed with other bryophytes such as
Isothecium stoloniferum, Scapania bolanderi, and Plagiochila porelloides.
Threats: Because most known sites are from mature or old-growth forests, the
primary threats to this species are logging and other forest disturbing
activities. It may also grow in habitats subject to "moss" harvest.
Conservation Considerations: See Conservation Assessment by Fredericks
and Sperling (2005). Consider managing areas around sites in old growth
forests, when projects (specifically logging) are proposed nearby.
Conservation Rankings and Status:
Global: G4; Oregon: S2
ORNHIC List 2
Washington: Not ranked
BLM/USFS Sensitive Species in Oregon
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Other pertinent information:
Survey Protocol: None.
Key to Identification of the Species: Christy and Wagner 1996; Doyle and
Stotler 2006.
Preparer: David H. Wagner
Edited by: Rob Huff
Date Completed: October, 2008
Updated in May 2009 by Candace Fallon (Update added Attachment 1, Photos,
to the Species Fact Sheet).
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.
Doyle, W. T. & R.E. Stotler. 2006. Contributions toward a bryoflora of
California III. Keys and annotated species catalogue for liverworts and
hornworts. Madroño 53: 89-197.
Frye, T.C. & L. Clark. 1946. Hepaticae of North America. No. 4. University of
Washington Publications in Biology 6: 565-734.
Hutten, M, A. Woodward, and 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.
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
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Potemkin, A. D. 1999. Circumscription of the family Scapaniaceae, with
segregation of the new family Diplophyllaceae (Hepaticae). Annales
Botanici Fennici 36: 271--283.
Schofield, W.B., S.S. Talbot, and S.L. Talbot. 2004. Bryophytes from Simeonof
Island in the Shumagin Islands, southwestern Alaska. Jour. Hattori Bot.
Lab. 95: 155-198.
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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Attachment 1 – Photos
All photos by Dr. David Wagner, under contract with the Oregon/Washington Bureau of Land
Management.
Shoot
Ventral shoot 4x
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Ventral 10x
Oil-bodies in vitta
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