SPECIES FACT SHEET
Common Name: Bug-on-a-stick, hump-backed elf, elf cap moss
Scientific Name: Buxbaumia aphylla
Division: Bryophyta
Class: Bryopsida
Order: Buxbaumiales
Family: Buxbaumiaceae
Technical Description: Protonema persistent, yellow green to dark
green, dense and felty, coating the substrate in a nearly solid mat. Leafy
plants reduced to a tiny cluster of bracts surrounding the gametangia, to
0.5 mm tall. Seta 3-12 mm long, dark brown, papillose. Capsule ovoid,
yellow-brown to reddish-brown, glossy, 3-7 mm long and sometimes
nearly as wide, inclined but often nearly horizontal, usually flattened on
top and rounded beneath, often with a distinct ridged margin. Peristome
at the distal end of the capsule but often oriented toward the dorsal side
and pointing above the plane of the capsule, sometimes set back slightly
from the margin. When the capsule matures, the papery cuticle
separates from the wall of the capsule, and peels backward from the
mouth, like a scroll of parchment. Sometimes the cuticle remains
smooth, and does not split or peel at all. Distinctive characters: (1) A
green, felty protonema, (2) capsule with conspicuous glossy rim, (3) a
cuticle that curls back from the mouth of the capsule, and (4) dry,
mineral-poor soil or decayed wood in shade to full sun. Similar species:
The capsules of Buxbaumia viridis and B. piperi are usually oriented at a
45º angle from the seta, and the peristome points more or less parallel to
the plane of the capsule. B. viridis has a cuticle that splits longitudinally
along the top of the capsule, peeling back toward the sides, rather than
from the mouth toward the base, as in B. aphylla and B. piperi. Other
descriptions and illustrations: Crum 1983: 362; Crum & Anderson
1981: 1235; Ireland 1982: 655; Lawton 1971: 29; Smith 1978: 106
Life History: The life history of Buxbaumia is better known than many
other mosses because of its peculiarity and celebrity status (Hancock
and Brassard 1974). The persistent protonema grows and spreads on
exposed substrate before sporophytes develop. Leaves are strongly
reduced and functionally absent. Photosynthesis primarily restricted to
the persistent protonema and immature green capsules. Protonema may
be associated with cyanobacteria and mycorrhizal fungi. Capsules most
easily identified in summer or fall. The species is a pioneer on disturbed
soils but is a poor competitor. Plants are ephemeral, documented as
appearing up to 15 years after fire but disappearing after a few seasons
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as competition increases from invading plants. Spores are wind-born but
may not travel far from parent plants. Green sporophytes are eaten by
herbivores and probably limit dispersal potential.
Range, Distribution, and Abundance: Circumboreal and New Zealand.
In North America, south to California, Colorado, and North Carolina. In
Oregon and Washington, mostly in the Cascade Range and Blue
Mountains.
National Forests: Documented on Deschutes, Fremont-Winema,
Malheur, Umpqua, Wallowa-Whitman, Willamette. Suspected on Rogue
River/Siskiyou NF. BLM Districts: Documented on Eugene District and
Klamath Falls Resource Area, Lakeview District. Suspected on Coos Bay
and Medford.
Rare but sometimes locally abundant. Probably undercollected.
Habitat Associations: A pioneer on dry, mineral-poor soil (sandy,
pumice, or clayey) and well-decayed wood, in exposed to shaded sites in
forests, cutbanks of trails and roads, and recovering burns. In Oregon
and Washington, elevation mostly 4000-6000 feet. Often associated with
other soil pioneers such as Cephaloziella, Cladonia, Funaria, Peltigera,
and Polytrichum. Forest associations include Abies concolor, Abies x
shastensis, Pinus contorta, Pseudotsuga menziesii, Tsuga heterophylla,
Tsuga mertensiana. It grows in a variety of conditions from no canopy to
closed canopy, and forest age class does not seem to be important. It
also favors drier, more open habitat than that of Buxbaumia viridis and
B. piperi.
Threats: Threats may include road and trail maintenance, fire, logging,
and plant succession. Buxbaumia is always considered a rarity although
it may be locally abundant. Despite its pioneer status on soil and
decayed wood, populations are usually small, discontinuous, and subject
to catastrophic loss. Dispersal may be limited by herbivory of
sporophytes (Van Rompu and Stieperaere 2002), short travel distance of
spores, and suspected associations with cyanobacteria and mycorrhizal
fungi. It probably does not compete well with vascular plants.
Conservation Considerations: Short of direct seeding of spores or
protonema on suitable substrate, little can be done to foster
establishment of new populations. Existing populations will disappear
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over time, but consider protecting them in the interim to enable the sites
to persist and allow for dispersal to new sites.
Preparer: John A. Christy
Date Completed: May 2006
Revised: Rob Huff, March 2009
(Revision only updated documented and suspected status of BLM
Districts).
Updated by Camille Duncan in January 2010 (Update added Attachment
1, Photos to Species Fact Sheet).
ATTACHMENTS:
(1)
Photos
References
Crum, H. 1983. Mosses of the Great Lakes Forest. 3rd edition. University
of Michigan Herbarium, Ann Arbor. 417 pp.
_______ & L.E. Anderson. 1981. Mosses of Eastern North America. 2
volumes. Columbia University Press, New York. 1328 pp.
Hancock, J.A., and G.R. Brassard. 1974. Phenology, sporophyte
production, and life history of Buxbaumia aphylla in Newfoundland,
Canada. Bryologist 77:501-513.
Idaho Conservation Data Center. 2006. Idaho's Special Status
Nonvascular Plants. Idaho Fish and Game.
http://fishandgame.idaho.gov/cdc/plants/nonvascular_plants_status
.cfm
Ireland, R.R. 1982. Moss flora of the Maritime Provinces. National
Museums of Canada Publications in Botany 13: 1-738. National
Museum of Natural Sciences, Ottawa.
Lawton, E. 1971. Moss Flora of the Pacific Northwest. Hattori Botanical
Laboratory, Nichinan, Japan. 362 pp.
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Oregon Natural Heritage Information Center. 2004. Rare, threatened and
endangered species of Oregon. Oregon Natural Heritage Information
Center, Oregon State University. Portland. 104 pp.
http://oregonstate.edu/ornhic/2004_t&e_book.pdf
Schofield, W. B. 2004. Buxbaumiaceae. Bryophyte Flora of North
America, Provisional Publication, Missouri Botanical Garden.
http://www.mobot.org/plantscience/bfna/V1/BuxbBuxbaumiaceae.
htm
Smith, A.J.E. 1978. The Moss Flora of Britain and Ireland. Cambridge
University Press, Cambridge. 706 pp.
USDA Forest Service. (no date) Bug-on-a-Stick, Buxbaumia aphylla
Hedw. Sensitive Plant Species, Clearwater National Forest.
http://www.fs.fed.us/r1/clearwater/terra_org/plants/sensitive/htm/
buxbau.htm
Van Rompu, W. & H. Stieperaere. 2002. Fate of sporophytes in a Belgian
population of Buxbaumia aphylla. Journal of Bryology 24: 83-85.
Washington Natural Heritage Program. 2005. Working list of rare
mosses.
http://www.dnr.wa.gov/nhp/refdesk/lists/mosses.html
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Attachment 1- Photos
All photos by Dr. Judy Harpel, under contract with the Oregon/Washington Bureau of
Land Management.
Whole mount sporophyte
Sporophyte
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Peristome teeth
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