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orthotrichum moss

orthotrichum moss

Habit Plants 0.5–2.3 cm. Plants 0.4–1.2 cm.
Stem

leaves loosely erect-appressed and ± loosely twisted when dry, elongate- to ovate-lanceolate, 2–3.5 mm;

margins revolute to below apex, entire;

apex sharply acute, sometimes acuminate, cuspidate, or apiculate;

basal laminal cells long-rectangular to rectangular, walls thin, sometimes nodose at insertion;

distal cells 9–14 µm, 1-stratose, papillae 2 or 3 per cell, conic or 2-fid, large.

leaves erect-appressed when dry, ovate to ovate-oblong, 2–2.8 mm;

margins involute, entire;

apex rounded to obtuse;

basal laminal cells elongate-rectangular, walls thick, not nodose;

distal cells 7–12 µm, 1-stratose, papillae 2 or 3 per cell, conic, small.

Seta

to 1.4 mm.

0.5 mm.

Sexual condition

gonioautoicous.

dioicous.

Capsule

1/2–3/4 emergent, sometimes almost exserted, oblong-ovate when mature, oblong to short-cylindric when old and dry, to 1.4 mm, strongly 8-ribbed 2/3 to entire length, constricted below mouth when dry;

stomata immersed, 1/2 covered by subsidiary cells, cells projecting, inner walls thickened;

peristome double;

prostome absent;

exostome teeth 8, reflexed, densely and evenly papillose, striate-reticulate distally;

endostome segments 8 or 16, well developed, of 1 or 2 rows of cells, smooth or finely roughened.

immersed, oblong, 1.8 mm, moderately 8-ribbed when dry;

stomata superficial;

peristome and prostome absent.

Calyptra

oblong, smooth, ± hairy, hairs strongly papillose.

conic, papillose, naked, obscurely plicate.

Spores

10–15 µm.

18–20 µm.

Specialized

asexual reproduction on leaves.

asexual reproduction by gemmae on adaxial surface of leaves.

Orthotrichum alpestre

Orthotrichum gymnostomum

Habitat Rock, trees, base of trees, moist crevices of large boulders, moist pine and deciduous forests Bark of deciduous trees
Elevation high elevations (2100-3000 m) (high elevations (6900-9800 ft)) low to moderate elevations (0-200 m) (low to moderate elevations (0-700 ft))
Distribution
from FNA
AZ; CA; CO; ID; MI; MT; NM; NV; OR; SD; UT; WA; WY; AB; BC; NL; ON; YT; Asia; Greenland; Europe; Pacific Islands (New Zealand)
[WildflowerSearch map]
from FNA
NF; Europe; e Asia (Japan)
Discussion

Orthotrichum alpestre is distinguished by the highly papillose distal laminal cells; slightly twisted, sharply pointed leaves; calyptra with papillose hairs; absence of prostome; and papillose or papillose-reticulate exostome. The endostome is always present in mature capsules and, because of enlarged cross walls, has a shiny appearance. The capsule is usually oblong and strangulate, although the shape depends on age. In some specimens, the capsule is short-cylindric and not much constricted below the mouth. The stomata are found just below mid capsule.

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

Orthotrichum gymnostomum differs from the similar O. obtusifolium by its leaves with involute margins, laminal cells with two or three papillae, and immersed capsules with no peristome, while O. obtusifolium has leaves with erect margins, 1-papillose cells, and emergent capsules with a double peristome. Orthotrichum gymnostomum is rare in North America, restricted to the coastal areas of Newfoundland.

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

Source FNA vol. 28, p. 50. FNA vol. 28, p. 56.
Parent taxa Orthotrichaceae > Orthotrichum Orthotrichaceae > Orthotrichum
Sibling taxa
O. affine, 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. 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
Synonyms O. alpestre var. majus, O. alpestre var. watsonii, O. occidentale, O. watsonii Nyholmiella gymnostoma
Name authority Hornschuch ex Bruch & Schimper: Bryol. Europ. 3: 75, plate 213. (1849) Bruch ex Bridel: Bryol. Univ. 1: 782. (1827)
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