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orthotrichum moss, wood bristle-moss

xerophytic limestone moss

Habit Plants to 3 cm. Plants to 2.5 cm, appearing glaucous.
Stem

leaves erect-appressed and straight when dry, ligulate, elongate- to ovate-lanceolate, 2–4 mm;

margins recurved-revolute to just below apex, entire;

apex acute;

basal laminal cells long-rectangular to elongate, walls thick, nodose;

distal cells 9–13 µm, 1-stratose, papillae 2 or 3 per cell, 2-fid, low.

leaves stiff, closely erect-appressed, incurved when dry, oblong-lanceolate or lanceolate, 2–2.7 mm;

margins recurved proximally, reflexed distally, entire;

apex blunt or obtuse;

basal laminal cells short-rectangular to quadrate, grading to subquadrate at margin, walls thin, not nodose;

distal cells 6–11 µm, 1-stratose, papillae 1–3 per cell, conic or 2-fid, large.

Seta

1–2.2 mm.

1–1.5 mm.

Sexual condition

gonioautoicous.

gonioautoicous.

Capsule

1/2 emergent to short-exserted, long-cylindric when mature, cylindric and constricted along entire length when old and dry, 1.6–2.5 mm, strongly 8-ribbed 2/3 capsule length;

stomata superficial;

peristome double;

prostome absent;

exostome teeth 8, erect when mature, reflexed to reflexed-recurved when old, coarsely and obscurely papillose or sometimes papillose-reticulate, deeply perforate, cancellate;

endostome segments 8, rarely 16, well developed, usually present when capsule is old and dry, narrow, of 2 rows of cells, papillose.

1/2 emergent to short-exserted, oblong-ovate to ovate when mature, oblong to short-oblong when old and dry, 1.2–1.9 mm, strongly 8-ribbed entire length, rarely 16-ribbed with 8 short intermediate ribs, constricted below mouth when dry;

stomata immersed;

peristome single;

prostome rudimentary;

exostome teeth usually 16 when mature, irregularly split, often absent when capsule is old, erect or spreading, papillose-striate to coarsely reticulate-papillose;

endostome segments absent.

Calyptra

conic-oblong, smooth, hairs few, papillose.

oblong, smooth, hairy, hairs papillose.

Spores

15–18 µm.

10–15 µm.

Specialized

asexual reproduction absent.

asexual reproduction absent.

Orthotrichum affine

Orthotrichum pellucidum

Habitat Deciduous trees, shaded rock, shaded forests near stream beds, canyons, mountains Calcareous or siliceous boulders, cliff faces in xeric areas, direct sunlight
Elevation low to high elevations (0-3000 m) (low to high elevations (0-9800 ft)) moderate to high elevations (500- 3000 m) (moderate to high elevations (1600- 9800 ft))
Distribution
from FNA
CA; CO; ID; MT; OR; UT; WA; AB; BC; Europe; Asia; n Africa
[WildflowerSearch map]
from FNA
AK; AZ; CA; CO; ID; MT; NM; NV; OR; SD; UT; WY; AB; BC; MB; NT; NU; YT; Greenland; n Europe
Discussion

Orthotrichum affine, a species confined to western North America in the flora area, is best recognized by: superficial stomata; cylindric, strongly ribbed, almost exserted capsules; a well-developed but not stout endostome; and a calyptra that is only sparsely hairy.

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

Orthotrichum pellucidum is distinguished by its blunt, lanceolate-oblong leaves that always appear glaucous because of the large 2-fid papillae of the distal laminal cells. When the plants are fertile, which is usually the case, the short-exserted, oblong-ovate, 8-ribbed capsules identify O. pellucidum. The capsule has stomata in the proximal to mid capsule, more or less covered by projecting subsidiary cells.

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

Source FNA vol. 28, p. 50. FNA vol. 28, p. 62.
Parent taxa Orthotrichaceae > Orthotrichum Orthotrichaceae > Orthotrichum
Sibling taxa
O. alpestre, O. anodon, O. anomalum, O. bartramii, O. bolanderi, O. consimile, O. cupulatum, O. diaphanum, O. elegans, O. euryphyllum, O. exiguum, O. fenestratum, O. flowersii, O. gymnostomum, O. hallii, O. holzingeri, O. keeverae, O. kellmanii, O. laevigatum, O. lescurii, O. lyellii, O. norrisii, O. obtusifolium, O. ohioense, O. pallens, O. parvulum, O. pellucidum, O. praemorsum, O. pulchellum, O. pumilum, O. pusillum, O. pycnophyllum, O. pylaisii, O. rivulare, O. rupestre, O. shawii, O. shevockii, O. sordidum, O. speciosum, O. spjutii, O. stellatum, O. stramineum, O. strangulatum, O. striatum, O. tenellum, O. underwoodii
O. affine, O. alpestre, O. anodon, O. anomalum, O. bartramii, O. bolanderi, O. consimile, O. cupulatum, O. diaphanum, O. elegans, O. euryphyllum, O. exiguum, O. fenestratum, O. flowersii, O. gymnostomum, O. hallii, O. holzingeri, O. keeverae, O. kellmanii, O. laevigatum, O. lescurii, O. lyellii, O. norrisii, O. obtusifolium, O. ohioense, O. pallens, O. parvulum, O. praemorsum, O. pulchellum, O. pumilum, O. pusillum, O. pycnophyllum, O. pylaisii, O. rivulare, O. rupestre, O. shawii, O. shevockii, O. sordidum, O. speciosum, O. spjutii, O. stellatum, O. stramineum, O. strangulatum, O. striatum, O. tenellum, O. underwoodii
Synonyms O. cupulatum var. jamesianum, O. jamesianum
Name authority Schrader ex Bridel: Muscol. Recent. 2(2): 22. (1801) Lindberg: Öfvers. Kongl. Vetensk.-Akad. Förh. 23: 549. (1867)
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