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grimmia dry rock moss, hair-point grimmia

grimmia dry rock moss, twisted grimmia

Habit Plants in dense to loose patches, yellowish green to dark green. Plants in soft, readily disintegrating cushions, yellow-green to brownish, occasionally light green, blackish to red-brown inside.
Stems

2–4 cm, central strand present.

1–4 cm, small central strand present.

Gemmae

clusters occasionally present in distal leaf axils.

brown, multicellular, present on the abaxial side of distal leaves.

Leaves

loosely appressed, slightly twisted when dry, erecto-patent when moist, lanceolate to oblong-lanceolate, tapering to acute apex, 2–3.5 × 0.3–0.4 mm, usually sharply keeled, margins recurved on one or both sides, plane to erect distally, awns variable, short to long, smooth to denticulate, not conspicuously flattened at base, costa firm, projecting on abaxial side;

basal juxtacostal laminal cells long-rectangular (rarely short-rectangular), ± nodulose, thick-walled;

basal marginal laminal cells short- to long-rectangular, with thickened transverse walls;

medial laminal cells quadrate to short-rectangular, slightly sinuose, thick-walled;

distal laminal cells 1-stratose, occasionally with 2-stratose ridges.

contorted when dry, patent when moist, lanceolate, 1.5–2 × 0.3–0.5 mm, keeled, margins slightly recurved proximally, plane distally, awns very short and smooth, occasionally absent, costa weak proximally, projecting on abaxial side;

basal juxtacostal laminal cells linear, extremely sinuose, thick-walled;

basal marginal laminal cells long rectangular, thin-walled, hyaline;

medial laminal cells rectangular, extremely sinuose, thick-walled;

distal laminal cells 1-stratose.

Seta

arcuate, 2–4 mm.

slightly curved, straight when dry, 3–5 mm.

Sexual condition

dioicous.

dioicous.

Capsule

occasionally present, exserted, oblong-ovoid, yellowish green to stramineous, striate when dry, exothecial cells thin-walled, annulus present, operculum rostrate, peristome teeth yellowish, papillose, deeply split and perforated.

sporadically present, exserted, ovoid, brown, smooth, striate when dry and empty, exothecial cells thin-walled, annulus present, operculum rostrate, peristome teeth yellowish, short, split in distal part, weakly papillose.

Calyptra

mitrate.

mitrate.

Grimmia trichophylla

Grimmia torquata

Habitat Dry, acidic rock Damp, frequently vertical faces of acidic rock
Elevation moderate to high elevations (200-2000 m) [moderate to high elevations (700-6600 ft)] moderate to high elevations (200-4000 m) [moderate to high elevations (700-13100 ft)]
Distribution
from FNA
AZ; CA; CO; ID; ME; MO; MT; NV; OK; OR; SD; UT; VT; WA; WY; HI; BC; Mexico; Eurasia; Australia
[WildflowerSearch map]
from FNA
AK; AZ; CA; CO; ID; MT; NV; OR; WA; WY; HI; AB; BC; NL; NT; ON; QC; YT; Mexico; Eurasia; n Africa; Greenland
[WildflowerSearch map]
Discussion

In North America, Grimmia trichophylla is principally a lowland species, occurring in the mountains up to about 1000 m., rarely higher. In the Southern Hemisphere, it may be found up to 4000 m. In New Zealand, the species is common, and in contrast to G. trichophylla in North America, frequently bears capsules. The New Zealand plants are usually smaller than American specimens, and the leaves are frequently contorted. The nearly cosmopolitan G. trichophylla has many phenotypes, and numerous subspecies and varieties have been described. In damp and shaded habitats, the awns may be short, just as in dry unfavorable habitats at high altitudes, where stunted specimens may occur with small, short leaves and reduced awns, or even with muticous leaves. Grimmia trichophylla has frequently been confused with related species such as 36. G. muehlenbeckii and 34. G. lisae (see discussions thereunder for identification details). Robust forms of G. trichophylla have been mistaken for G. austrofunalis (H. C. Greven 1997, 2003), which does not occur in North America. Although some of those plants have leaves of equal length along the stem, characteristic of G. austrofunalis, they also have both leaf margins recurved, and the medial and outer basal laminal cells are longer and more robust than in that species.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Grimmia torquata is a montane-alpine species with a preference for shaded habitats. It grows in hemispherical cushions on steep, damp rock walls. Preferred substrates are granite, gneiss, quartzite, and schist. Its distribution reaches from near sea level in the Arctic to above 4000 m on Mexican and Hawaiian volcanoes. The species is easily recognized by its yellow-brown cushions of plants, which have contorted leaves when dry, and their brown gemmae, which are borne at the bases of older leaves. In densely shaded habitats, the cushions are light green; on exposed rock, they are usually brown. Although the species has a wide distribution, it is seldom present in quantity, usually growing in a small number of cushions in one habitat. Sporophytes are very rare worldwide and have not been found in eastern North America (H. A. Crum and L. E. Anderson 1981).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 27, p. 257. Treatment authors: Roxanne I. Hastings, Henk C. Greven. FNA vol. 27, p. 256. Treatment authors: Roxanne I. Hastings, Henk C. Greven.
Parent taxa Grimmiaceae > subfam. Grimmioideae > Grimmia > subg. Rhabdogrimmia Grimmiaceae > subfam. Grimmioideae > Grimmia > subg. Rhabdogrimmia
Sibling taxa
G. alpestris, G. americana, G. anodon, G. anomala, G. arizonae, G. atrata, G. attenuata, G. brittoniae, G. caespiticia, G. crinitoleucophaea, G. donniana, G. elatior, G. elongata, G. funalis, G. hamulosa, G. hartmanii, G. incurva, G. laevigata, G. leibergii, G. lesherae, G. lisae, G. longirostris, G. mariniana, G. mollis, G. montana, G. moxleyi, G. muehlenbeckii, G. nevadensis, G. olneyi, G. orbicularis, G. ovalis, G. pilifera, G. plagiopodia, G. pulvinata, G. ramondii, G. reflexidens, G. serrana, G. sessitana, G. shastae, G. teretinervis, G. torquata, G. unicolor
G. alpestris, G. americana, G. anodon, G. anomala, G. arizonae, G. atrata, G. attenuata, G. brittoniae, G. caespiticia, G. crinitoleucophaea, G. donniana, G. elatior, G. elongata, G. funalis, G. hamulosa, G. hartmanii, G. incurva, G. laevigata, G. leibergii, G. lesherae, G. lisae, G. longirostris, G. mariniana, G. mollis, G. montana, G. moxleyi, G. muehlenbeckii, G. nevadensis, G. olneyi, G. orbicularis, G. ovalis, G. pilifera, G. plagiopodia, G. pulvinata, G. ramondii, G. reflexidens, G. serrana, G. sessitana, G. shastae, G. teretinervis, G. trichophylla, G. unicolor
Synonyms G. pellucida, G. prolifera, G. pseudotorquata, G. tortifolia
Name authority Greville: Fl. Edin., 235. (1824) Drummond: Musc. Scot. 2: no. 28. (1825)
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