Schistidium rivulare

(Bridel) Podpera

Beih. Bot. Centralbl. 28(2): 207. 1911,.

Basionym: Grimmia rivularis Bridel J. Bot. (Schrader) 1800(1): 276. 1801
Synonyms: Grimmia alpicola var. rivularis (Bridel) Wahlenberg Grimmia platyphylla (Mitten) Persson Schistidium platyphyllum Schistidium rivulare subsp. latifolium (J. E. Zetterstedt) Bremer Schistidium submuticum subsp. arcticum H. H. Blom
Treatment appears in FNA Volume 27. Treatment on page 222. Mentioned on page 209, 211, 223.

Plants in open to compact, often extensive, tufts or mats, dark green, olivaceous, or brown, often yellow green distally, rarely nearly black. Stems 1.2–10 (–18) cm, central strand distinct. Leaves erect, often curved towards stem when dry and somewhat imbricate, sometimes secund, often slightly contorted when dry, ovatelanceolate to ovate-triangular, keeled or concave proximally, keeled distally, 1.2–3.2 mm, 1-stratose, occasionally with 2-stratose striae or patches distally; margins usually recurved to past mid leaf, sometimes to near apex, rarely plane, denticulate or smooth distally, 1-stratose or 2-stratose, rarely 3-stratose, often in more than one row; apices acute or obtuse, sometimes ending in a series of pellucid cells; costa subpercurrent or percurrent, sometimes as a short, smooth or weakly denticulate awn, smooth; basal marginal cells mostly quadrate; distal laminal cells angular, isodiametric or short-rectangular, 7–9 (–11) µm, smooth, slightly sinuose. Sexual condition autoicous. Capsule redbrown or yellowish green, rarely almost black, short-cylindric, cupulate, or campanulate, 0.6–1.1 mm; exothecial cells isodiametric, usually irregularly angular, or elongate, sometimes rounded, unevenly thickened or thick-walled, often trigonous; rim usually darker than capsule wall; stomata present; peristome patent, squarrose-recurved, or revolute, 350–570 µm, dark red, densely papillose, usually weakly perforated. Spores 14–24 µm, granulose.


Phenology: Capsules mature late spring to early summer.
Habitat: Wet to dry rocks in or along water courses and lakes, sometimes along seasonally irrigated ledges or cliffs, rarely on concrete or mineral soil
Elevation: low to high elevations (0-4600 m)

Distribution

V27 304-distribution-map.gif

Greenland, Alta., B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.W.T., N.S., Nunavut, Ont., P.E.I., Que., Sask., Yukon, Alaska, Ariz., Calif., Colo., Conn., Del., Idaho, Ill., Ind., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.Dak., Tenn., Utah, Vt., Va., Wash., W.Va., Wis., Wyo., South America, Eurasia, Africa, Atlantic Islands, Australia, Antarctic

Discussion

Schistidium rivulare is the most variable and widely distributed species of the genus in North America. A myriad of forms have been recognized at various taxonomic levels, but none more than the smaller and more triangular-leaved form (e.g., S. platyphyllum and S. rivulare subsp. latifolium). H. H. Blom (1998) separated S. platyphyllum mainly using the thickness and shape of the exothecial cells, with S. rivulare having short, thick-walled, irregular cells and S. platyphyllum having more or less regular, thin-walled, and elongate cells. These features, however, at least within North American specimens, vary from place to place and sometimes between capsules in the same collection. Other characters used to separate the taxa, such as the more keeled leaves of S. rivulare and its absence of an awn, also are variable. Differences between S. rivulare and the closely related S. subjulaceum are discussed under the latter species. Schistidium rivulare is sometimes confused with S. agassizii, also found along watercourses, but it is readily separated by its more ovate, distally keeled leaves with recurved margins. Schistidium alpicola Hedwig is a name that has been frequently applied to this complex, but is no longer useful (see Blom for further discussion).

Selected References

None.

Lower Taxa

None.

"um" is not declared as a valid unit of measurement for this property.

... more about "Schistidium rivulare"
deciduous +  and persistent +
obtuse +  and acute +
multistratose +
Terry T. McIntosh +
(Bridel) Podpera +
not papillose +
denticulate +
sinuous +  and straight to sometimes +
rectangular +
divided +
Grimmia rivularis +
undifferentiated +
plicate +  and smooth +
not papillose +
mitrate +  and cucullate +
small;large +
sulcate +  and smooth +
black +, yellowish green +  and redbrown +
long-exserted +
striate +  and smooth +
campanulate;cupulate;campanulate;cupulate;short-cylindric +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
thin +  and thick +
subpercurrent +
reniform +, elliptical +  and terete +
usually not markedly larger +
2-stratose +  and 1-stratose +
autoicous +  and sexual +
short-rectangular +, isodiametric +  and angular +
Greenland +, Alta. +, B.C. +, Man. +, N.B. +, Nfld. and Labr. (Nfld.) +, N.W.T. +, N.S. +, Nunavut +, Ont. +, P.E.I. +, Que. +, Sask. +, Yukon +, Alaska +, Ariz. +, Calif. +, Colo. +, Conn. +, Del. +, Idaho +, Ill. +, Ind. +, Iowa +, Kans. +, Ky. +, Maine +, Md. +, Mass. +, Mich. +, Minn. +, Miss. +, Mo. +, Mont. +, Nebr. +, Nev. +, N.H. +, N.J. +, N.Mex. +, N.Y. +, N.C. +, N.Dak. +, Ohio +, Okla. +, Oreg. +, Pa. +, R.I. +, S.Dak. +, Tenn. +, Utah +, Vt. +, Va. +, Wash. +, W.Va. +, Wis. +, Wyo. +, South America +, Eurasia +, Africa +, Atlantic Islands +, Australia +  and Antarctic +
low to high elevations (0-4600 m) +
trigonous +, rounded +, elongate +, angular +  and isodiametric +
reproduction +  and asexual +
dioicous +, autoicous +  and sexual +
Wet to dry rocks in or along water courses and lakes, sometimes along seasonally irrigated ledges or cliffs, rarely on concrete or mineral soil +
papillose +, mammillose +  and smooth +
specialized +
dioicous +, autoicous +  and sexual +
flat +, keeled +, , +, concave +, less commonly lanceolate +  and linear-lanceolate or elliptical +
3-stratose;2-stratose;1-stratose +
denticulate +  and plane +
thick-walled +  and sinuose +
papillose +  and smooth +
subtriangular +, ovate +, rectangular +  and quadrate +
thick-walled +  and sinuose +
papillose +  and smooth +
not +  and differentiated +
squarrose-recurved +  and patent +
lanceolate;linear +
Capsules mature late spring to early summer. +
Beih. Bot. Centralbl. +
usually darker +
straight +
sigmoid +  and arcuate +
papillose +  and smooth +
short to long +
ornamented +  and smooth +
globose +
1-stratose +  and secund +
10 cm100 mm <br />0.1 m <br /> (18 cm180 mm <br />0.18 m <br />) +
keeled;ovatelanceolate;ovate-triangular keeled or concave proximally +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.32 cm3.2 mm <br />0.0032 m <br />) +
muticous;long-awned +
Grimmia alpicola var. rivularis +, Grimmia platyphylla +, Schistidium platyphyllum +, Schistidium rivulare subsp. latifolium +  and Schistidium submuticum subsp. arcticum +
Schistidium rivulare +
Schistidium +
species +
open +  and compact +
extensive +
4 cm40 mm <br />0.04 m <br /> (18 cm180 mm <br />0.18 m <br />) +
black;yellow green;brown;olivaceous;brown;olivaceous;dark green +