Grimmia unicolor

Hooker in R. K. Greville

in R. K. Greville, Scott. Crypt. Fl. 3: plate 123. 1824,.

Treatment appears in FNA Volume 27. Treatment on page 243. Mentioned on page 228, 244.

Plants in dense to loose patches, pale green to redbrown. Stems 1.5–4 (–5) cm. Leaves narrowly oblong-lanceolate to ligulate from an ovate base, 1.5–2.5 × 0.5–0.7 mm, both margins incurved, intermarginal bands absent, often sheathing, muticous, cucullate, obtuse-rounded, costa narrow proximally; basal juxtacostal laminal cells short-rectangular, straight, thick lateral walled, pale-yellow; basal marginal laminal cells short-rectangular, straight, thick lateral walled, pale-yellow, hyaline; medial laminal cells rounded to quadrate, straight, thick-walled; distal laminal cells 2–3-stratose, rounded, thick-walled. Perichaetial leaves enlarged. Seta straight to slightly sigmoid, 2–4 mm. Capsule occasionally present, exserted, brown, oblong-ovoid, exothecial cells short-rectangular, thin-walled, stomata present, annulus of 2–3 rows of rectangular, thick-walled cells, operculum long-rostrate, peristome perforate and split in distal half. Calyptra mitrate.


Habitat: Cracks of wet acidic, siliceous rocks especially along streams or splash zones of lake shores
Elevation: moderate to high elevations (200-2000 m)

Distribution

V27 332-distribution-map.gif

Greenland, B.C., Nfld. and Labr. (Nfld.), Ont., Que., Alaska, Calif., Maine, Mich., Minn., N.Y., Vt., Eurasia, Africa (Ethiopia)

Discussion

In Canada, Grimmia unicolor is found predominantly around the Great Lakes of southern Ontario eastward into southwestern Quebec, with a disjunct site in Newfoundland. In the United States, it is also commonly found in the Great Lakes region and extending eastward into southwestern Maine. The disjunct sites in British Columbia and on the Seward Peninsula may be a Beringial link with populations in Asia, where this species is widely distributed, and in northern Europe. Grimmia unicolor is often found in the splash zone of rocky shorelines, especially cliffs, and along rivers. This habitat is rarely occupied by other species of the genus, except for G. olneyi. Grimmia unicolor is readily distinguished from other species in the subgenus by its leaf morphology. Its leaves are oblong-lanceolate to ligulate, with an obtuse, rounded apex which is muticous. Grimmia olneyi has an acute leaf apex with long awns, and its basal marginal cells are quadrate, contrasting with the rectangular cells of G. unicolor. Sporophytically, G. unicolor typically has a straight seta while that of G. olneyi is sigmoid. Grimmia unicolor has a much narrower costa proximally and lacks an awn, in marked contrast to the broad costa and robust awn of G. laevigata. The leaf shapes of these two species are distinct, with G. unicolor having a pronounced ovate base and narrow leaves tending towards being ligulate, while G. laevigata has broadly oblong-ovate leaves without a shoulder separating the distal and proximal lamina.

Selected References

None.

Lower Taxa

None.
... more about "Grimmia unicolor"
deciduous +  and persistent +
well-defined +
differentiated +
Roxanne I. Hastings +  and Henk C. Greven +
Hooker in R. K. Greville +
only rarely longer +
not papillose +
toothed +
sinuous +  and straight to sometimes +
sinuose-nodulose;quadrate;elongate +
oblate;elongate +
hyaline +  and pale-yellow +
undifferentiated +
plicate +  and smooth +
less +  and 1/2 +
not papillose +
small;medium +
sulcate +  and smooth +
pendent +  and erect +
striate +  and smooth +
oblong-ovoid +
thin +  and thick +
thick-walled +
rectangular +
excurrent;percurrent;excurrent +
subpercurrent +
reniform +, elliptical +  and terete +
usually not markedly larger +
thick-walled +  and 2-3-stratose +
Greenland +, B.C. +, Nfld. and Labr. (Nfld.) +, Ont. +, Que. +, Alaska +, Calif. +, Maine +, Mich. +, Minn. +, N.Y. +, Vt. +, Eurasia +  and Africa (Ethiopia) +
moderate to high elevations (200-2000 m) +
short-rectangular +
reproduction +  and asexual +
dioicous +  and sexual +
Cracks of wet acidic, siliceous rocks especially along streams or splash zones of lake shores +
obtuse-rounded +, cucullate +  and muticous +
papillose +, mammillose +  and smooth +
specialized +
dioicous +, autoicous +  and sexual +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
oblong-lanceolate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
1;multistratose +
rounded +  and quadrate +
thick-walled +  and sinuose +
thick-walled +  and sinuose +
long-rostrate +
not +  and differentiated +
lanceolate;linear +
in R. K. Greville, Scott. Crypt. Fl. +
straight +  and slightly sigmoid +
sigmoid +  and arcuate +
papillose +  and smooth +
short to long +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
ornamented +  and smooth +
globose +
4 cm40 mm <br />0.04 m <br /> (5 cm50 mm <br />0.05 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (4 cm40 mm <br />0.04 m <br />) +
muticous;long-awned +
Dryptodon +  and Hydrogrimmia +
Grimmia unicolor +
Grimmia subg. Litoneuron +
species +
4 cm40 mm <br />0.04 m <br /> (7 cm70 mm <br />0.07 m <br />) +
pale green;redbrown +