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BFNA Title: Eurhynchiastrum |
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XX. Eurhynchiastrum Ignatov & Huttunen, Arctoa 11: 260. 2002 [2003] * [Eurhynchium, and Latin -astrum,
incomplete resemblance] Michael S.
Ignatov Plants small to
medium-sized, in loose to dense tufts, green or yellowish to brownish,
glossy. Stems prostrate to
arching, with central strand, loosely to densely terete-foliate, rather
irregularly densely branched, branches obtuse by smaller, more crowded and
more obtuse leaves at their tips; axillary hairs 3--4-celled; juvenile branch
leaves acute. Stem leaves loosely to closely imbricate or somewhat
spaced, erect to erectopatent, braodly ovate-triangular to ovate-lanceolate,
broadest at 1/10 of leaf length or below, gradualy tapered to apex or broadly
acuminate, sometimes blunt at apex, rounded to base, narrowly decurrent,
slightly concave, smooth or in large plants plicate, margins plane or
recurved near base, serrulate to subentire; costa strong, reaching 0.6--0.85
of leaf length, ending in a spine; basal cells near costa only slightly
shorter, not diffferentiated from above cells, cells just proximal to
decurrency broader, isodiametric, relatively thin-walled, forming a small,
more or less distinct subquadrate group and often surrounded by small
subquadrate cells forming more or less extensive indistinctly delimited group;
mid leaf cells linear, smooth. Branch leaves smaller and narrower than
stem leaves, rarely othercharacteristically blunt, smooth or in large plants
plicate, costa to 0.6--0.9 of leaf length, cells just before apex short,
nearly isodiametric or irregular in shape. Sexual condition
phyllodioicous or dioicous; perichaetial leaves reflexed, gradually acuminate
from a sheathing base, entire or occasionally serrulate, costa weak and
short, reaching to about half of basal part of leaf. Seta red-brown, smooth
or rarely very slightly rough at places. Capsule red-brown, inclined
to horizontal, oblong, slightly curved dorsally, annulus separating by
fragments; operculum rostrate; peristome perfect. Calyptra naked. Spores 12--17 /um, slightly
papillose. Species 1 (1
in the flora): North America, Central America, Eurasia, Africa, Eurhynchiastrum was segregated from the polyphyletic Eurhynchium (M. S. Ignatov and S.
Huttunen 2002), where it was placed by most authors. Other authors, e.g. G.
De Notaris (1867), H. Robinson (1987) and K. D. McFarland (2004), accepted
its placement in Rhynchostegium.
North American species of Rhynchostegium
differ from Eurhynchiastrum in
their robust habit and lack of a spine at end of costa. In the present
concept, Eurhynchium is strictly a
Palearctic genus. SELECTED
REFERENCE Grout, A. J. 1898. A
revision of the North American Eurhynchia. Bull. Torrey Bot. Club 25:
221--256. 1. Eurhynchiastrum pulchellum (Hedwig)
Ignatov & Huttunen, Arctoa 11: 262. 2002 [2003] Hypnum pulchellum Hedwig,
Sp. Musc. Frond. 265, plate 68:
figs. 1--4. 1801; Eurhynchium pulchellum (Hedwig) Stems 2--5(--13) cm, branches to 3--8(--17)
mm. Stem leaves 0.5--1.3(--2.6) x 0.2--0.9(--1.8) mm; basal cells near
costa 7--10 /um wide; cells just proximal to decurrency 12--20 x 10--15
/um; /um.mid-leaf
cells 30--75(--100) x 4.5--6 Branch
leaves 0.4--1.3(--1.6) x 0.2--0.5(--1.1) mm; Seta 1--1.8 cm. Capsule
1.5 mm. Varieties 2 (2
in the flora). The
species is easy to recognize by the characteristically blunt branch leaves.
The most common phenotype for plants on soil and tree trunk bases in forests
is of light green plants with rigid erect leaves. In xeric and Arctic
environments leaves (of both stems and branches) become strongly appressed,
with shoots julaceous, and these plants are often brownish and quite fragile.
They have been segregated as var. praecox
(temperate areas, branch leaves 0.5--0.8 mm, alar cells as in typical
variety) and var. diversifolium (Arctic-alpine,
branch leaves 0.5--0.6 mm, alar cells very numerous) but these grade to
typical phenotypes and thus do not merit taxonomic recognition despite a
sometimes distinctive appearance. The seta is almost always smooth in this
species, but some few collections, described as Eurhynchium strigosum var. scabrisetum
Grout, from 1.
Stem leaves 0.5--1.3 mm long; branch leaves 0.2--1.1 x 0.2--0.5(--0.6) mm,
not or slightly plicate . . . 1a. Eurhynchiastrum
pulchellum var. pulchellum 1.
Stem leaves 1.2--2.6; branch leaves 1--1.9 x 0.4--0.8(--1) mm, strongly
plicate . . . 1b. Eurhynchiastrum
pulchellum var. barnesii 1a. Eurhynchiastrum pulchellum
(Hedwig) Ignatov &
Huttunen var. pulchellum Eurhynchiastrum
pulchellum var. diversifolium (Schimper)
Ochyra & Żarnowiec; E. pulchellum var. praecox
(Hedwig) Ochyra & Żarnowiec; Eurhynchium fallax (Renauld & Cardot) Grout, E. substrigosum Kindb.; E.
pulchellum var. robustum (Roll)
Stems 2--10 cm. Stem leaves 0.5--1.3 x 0.4--0.9 mm. Branch leaves 0.2--1.1 x
0.2--0.5(--0.6) mm, not or slightly plicate. Soil in
forests, rocks, decaying logs and stumps, tree bases, in a broad range of
environmental conditions from shady rock vertical surfaces and wet slopes of
forested ravines to open ground in xeric steppe areas, and among other mosses
in tundra, granite, limestone; 0--3200 m; Greenland; Alta., B.C., Man., N.B.,
Nfld. and Labr., N.W.T., N.S., Nunavut, Ont., Que., Sask., Yukon; Ala., Alaska,
Ariz., Ark., Calif., Colo., Conn., Del., Ga., Idaho,
Ill., Ind., Iowa, Kans.,
Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., N.H., N.J.,
N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., S.C., S.Dak., Tenn.,
Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo. Mexico; Central America;
Eurasia; n and e Africa. Sporophytes of
E. pulchellum var. pulchellum are rare, confined probably
to forest environments. There are no collections from a few states and
provinces, but the var. pulchellum
apparently occurs throughout the flora area with probably the only exception
of 1b. Eurhynchiastrum pulchellum
var. barnesii (Renauld & Cardot)
Ignatov, xxxxxxx. 2008 Eurhynchium
strigosum var. barnesii
Renauld & Cardot, Revue
Bryologique 15: 72. 1888; E. pulchellum var. barnesii (Renauld & Cardot) H. A.
Crum, W. C. Steere & L. E.
Anderson; E. taylorae R. S.
Williams Stems 6--13 cm. Stem leaves 1.2--2.6 x 0.6--1.8 mm. Branch leaves 1--1.9 x 0.4--0.8(--1)
mm, often broadly obtuse, strongly plicate. Soil, rocks,
and decaying logs; probably middle elevations; ca. 500 m; Alta., B.C.; Alaska,
Calif., Colo., Idaho, Mont.,
Wash. The var. barnesii seems to be a relatively rare
and endemic plant, probably deserving the status of species. Its separation
from the large expressions of var. pulchellum
needs additional attention. OTHER
REFERENCES: Crum, H., W. C. Steere and L. E. Anderson 1965 [1966]. A
list of the mosses of De
Notaris, G. 1867. Cronaca della briologia italiana. Comment. Soc. Crittog. Ital. 2: 269--312. Ignatov,
M. S. and S. Huttunen 2002 [2003]. Brachytheciaceae (Bryophyta)---a family of
sibling genera. Arctoa 11: 245--296. McFarland,
K. D. 2004. Rhynchostegium. In: A.
J. Sharp et al., eds. The moss flora of Norris,
D. H. and J. R. Shevock. 2004. Contributions toward a bryoflora of Robinson,
H. 1987. Notes on generic concepts in the Brachytheciaceae and the new genus Steerecleus. Mem. Weber, W. A. and R. C. Wittmann. 2007. Bryophytes of |
