Search Field Guide
Advanced Search
MT Gov Logo
Montana Field Guide

Montana Field Guides

A Hook Moss - Drepanocladus polygamus
Other Names:  Campylium polygamum

Status Under Review
Native Species

Global Rank: G5
State Rank: SNR

Agency Status
MNPS Threat Rank:

External Links

General Description
Plants: Pleurocarpous (Vitt 1988). Growing in open to crowded, somewhat glossy mats, green with yellow or brown tinges to brown. Stems creeping to curving upward (Crum & Anderson et al. 1981), somewhat pinnate or freely forked, the scant branching in one plane; possessing a central strand; hyalodermis and paraphyllia wanting; rhizoids or their initials produced on the dorsal side of the costal attachment or on the stem, not forming woolly mats (FNA 2014).

Leaves: Stem leaves spreading to a little more upright, curved like a sickle or straight, egg-shaped, sometimes widely so, or deltoid with rounded angles, tapering to form a long acumen, cupped, 1.3-3.5 mm in length and 0.6 – 1.1 mm in width; margins smooth or sometimes wavy, unbordered; acumen grooved; base spreading to a little more upright; costa single (or eventually forked) and extending to half the leaf length or a little more or paired and not reaching mid leaf (FNA 2014), the double costa rare (Crum & Anderson et al. 1981).

Leaf Cells: Alar cells differentiated, swollen, transparent (FNA 2014) to golden (Crum & Anderson et al. 1981), the area forming a well-demarcated triangle across the leaf, extending from 2/3 to the entire distance from the leaf edge to the costa; marginal cells in 1 layer (FNA 2014); distal cells very thin (Crum & Anderson et al. 1981).

Diagnostic Characteristics
The similar Campylium stellatum has wider leaves that spread more (Crum & Anderson et al. 1981).

Range Comments
North American Range

AK to NL and NS, CA, WA sw to CO, MN s to MO, WI, OH, NY and scattered to ME, also FL (FNA 2014). Known in Montana from Flathead, Lewis and Clark, and Richland Counties (Elliott 2016).

Organic soil in meadows, forested bogs (Crum & Anderson et al. 1981), and other wetlands high in minerals and nutrients, underwater in lakes and ponds. Elevation: low to high (FNA 2014).

Reproductive Characteristics
Autoicous and polygamous. Seta mostly 1.5-3.5 (up to 5) mm tall (Crum & Anderson et al. 1981). Capsule bowed and level; margins of exostome smooth a little toothed above; endostome cilia knobby and sometimes transversely ridged (FNA 2014).

  • Literature Cited AboveLegend:   View Online Publication
    • Crum, H.A. and L.E. Anderson. 1981. Mosses of Eastern North America. 2 volumes. Columbia University Press, New York. 1328 pp.
    • Elliott, J.C. and A.K. Pipp. 2018. A Checklist of Montana Mosses (1880-2018). December 20th. Montana Natural Heritage Program, Helena, Montana. 73 pp.
    • Flora of North America Editorial Committee, eds. 2014. Flora of North America North of Mexico. Volume 28. Bryophytes: Mosses, Part 2. Oxford University Press, Inc., NY. xxi + 702 pp.
    • Vitt, D. J. Marsh, and R. Bovey. 1988. Mosses, Lichens & Ferns of Northwest North America. Seattle, WA: University of Washington Press. 296 p.
  • Additional ReferencesLegend:   View Online Publication
    Do you know of a citation we're missing?
    • Flowers, S. 1973. Mosses: Utah and the West. Brigham Young University, Provo, Utah. 567 p.
    • Lawton, E. 1971. Keys for the Identification of the Mosses on the Pacific Northwest. Reprinted from 'Moss Flora of the Pacific Northwest'. Published as Supplement No. 2 of the Journal of the Hattori Botanical Laboratory. Nichinan, Miyazaki, Japan. 66 pp.
    • Lawton, E. 1971. Moss Flora of the Pacific Northwest. Hattori Botanical Laboratory. Japan: Yamabuki-cho, Shinjuku-ku, Tokyo. 362 pages plus appendices.
    • Smith, A.J.E. 1980. The Moss Flora of Britain and Ireland. Cambridge University Press, Cambridge. 705 pp.
  • Web Search Engines for Articles on "A Hook Moss"
Login Logout
Citation for data on this website:
A Hook Moss — Drepanocladus polygamus.  Montana Field Guide.  .  Retrieved on , from