Status: Native
Synonyms:
Hypnum pratense Koch ex Spruce
Breidleria pratensis (Koch ex Spruce) Loeske
Stereodon pratensis is from a large group of mosses that used to grouped under the genus Hypnum, but
that now have been segregated into other genera and families. Stereodon pratensis is complanate foliate, meaning
that many or most of the stems have leaves that are flattened into one plane. The leaves have elongate cells and the
alar areas without obviously inflated cells. The leaf tips can be acuminate or not, and falcate or not. The costa is
short and double or almost missing. Two of the most important traits for identification of this moss are devilishly
difficult to see well. First, the stem has a hyalodermis-- inflated, thin walled cells on the outer surface. Unfortunately,
the hyalodermis is very fragile and most often it seems all is left is the thick walled cells which were just inside
the hyalodermis. The giveaway that there used to be a hyalodermis present is the appearance of what appear to be
papillae on either side of each thicker walled cell where the thinner walls of the hyalodermis used to attach. The second
important trait is the presence of foliose pseudoparaphyllia, the small structures around stem primordia and buds. These
foliose pseudoparaphyllia are difficult to see and narrow-- only 2-3 seriate at the base, which makes them appear filiform. This moss has been confused in New Mexico with Calliergonella lindbergii and other members of the former Hypnaceae, probably because of the
difficulty demonstrating some of the more important diagnostic features.
Many thanks to the University of Colorado Herbarium (COLO), Erin Tripp & Dina Clark for loaning this specimen for photography.
Please click on an image for a larger file.
Stereodon pratensis, collection and ID Dale H. Vitt (with T. Pocs), Canada, Alberta, N of Edmonton, 8km E of Dapp, W side of Muskeg Lake, September 18, 1980; photos by Russ Kleinman & Karen Blisard, May 4, 2023
Stereodon pratensis, dark field photomicrograph of stem, collection and ID Dale H. Vitt (with T. Pocs), Canada, Alberta, N of Edmonton, 8km E of Dapp, W side of Muskeg Lake, September 18, 1980; photos by Russ Kleinman & Karen Blisard, May 4, 2023
Stereodon pratensis, photomicrograph of leaf, collection and ID Dale H. Vitt (with T. Pocs), Canada, Alberta, N of Edmonton, 8km E of Dapp,W side of Muskeg Lake, September 18, 1980; photos by Russ Kleinman & Karen Blisard, May 4, 2023
Stereodon pratensis, photomicrograph of leaf, collection and ID Dale H. Vitt (with T. Pocs), Canada, Alberta, N of Edmonton, 8km E of Dapp, W side of Muskeg Lake, September 18, 1980; photos by Russ Kleinman & Karen Blisard, May 4, 2023
Stereodon pratensis, photomicrograph of stem hyalodermis (blue arrows), collection and ID Dale H. Vitt (with T. Pocs), Canada, Alberta, N of Edmonton, 8km E of Dapp, W side of Muskeg Lake, September 18, 1980; photos by Russ Kleinman & Karen Blisard, May 4, 2023
Stereodon pratensis, photomicrograph of stem hyalodermis (blue arrows), collection and ID Dale H. Vitt (with T. Pocs), Canada, Alberta, N of Edmonton, 8km E of Dapp, W side of Muskeg Lake, September 18, 1980; photos by Russ Kleinman & Karen Blisard, May 4, 2023
Stereodon pratensis, photomicrograph of leaf apex, collection and ID Dale H. Vitt (with T. Pocs), Canada, Alberta, N of Edmonton, 8km E of Dapp, W side of Muskeg Lake, September 18, 1980; photos by Russ Kleinman & Karen Blisard, May 4, 2023
Stereodon pratensis, photomicrograph of leaf base, collection and ID Dale H. Vitt (with T. Pocs), Canada, Alberta, N of Edmonton, 8km E of Dapp, W side of Muskeg Lake, September 18, 1980; photos by Russ Kleinman & Karen Blisard, May 4, 2023
Stereodon pratensis, photomicrograph of pseudoparaphylium, collection and ID A.J. Grout, Colorado, Gilpin County, near Tolland, July, 1914; photos by Russ Kleinman & Karen Blisard, May 4, 2023
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