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BFNA Title: Bryoandersonia |
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XX. Bryoandersonia
H. Robinson, Bryologist 65: 137. 1962 [1963] * [Bryum, a moss, and Lewis E.Anderson,
American bryologist, 1912--2007] Michael S. Ignatov Plants robust, rigid, green to
golden-brownish, in dense or moderately dense tufts. Stems prostrate or
more commonly ascending to erect when growing in dense tufts, with central
strand, densely, julaceously foliate, irregularly pinnately branched, often
quite congested; branch foliage similar to that of stem; axillary hairs
4--6-celled, distalmost cell obtuse, pale brown; juvenile branch leaves
acute. Stem leaves broadly ovate, broadly rounded to the apex, very
concave and densely imbricate at shoot ends (or in dense growth throughout
shoots), in older parts of shoots broadly ovate-triangular, short-acuminate,
less concave, and loosely imbricate, broadly rounded to the base and somewhat
auriculate, shortly and narrowly decurrent, rather slightly plicate; margin
serrate to serrulate, costa narrow, reaching 0.5--0.9 of leaf length, ending
without spine; basal laminal cells broader, with incrassate and strongly
porose cell walls, cells just proximal to decurrency broader than other basal
cells, subquadrate to short-rectangular, thick-walled, forming rather small
group of 2--4 x 4--6 cells; laminal cells linear, slightly flexuose,
moderately thick-walled. Branch leaves similar to stem leaves. Sexual
condition dioicous; perichaetial leaves reflexed, acuminate from loosely
sheathing base. Seta red to
red-brown, smooth. Capsule
inclined to horizontal, oblong, slightly curved, annulus separating by
fragments; operculum longly and broadly rostrate; peristome perfect. Calyptra
naked. Spores 13--17 µm, smooth. Species 1 (1
in the flora): North America. SELECTED
REFERENCE Robinson, H. 1962 [1963].
Generic revisions of North American Brachytheciaceae. Bryologist 65: 73--146. Bryoandersonia was segregated by H. Robinson (1962)
from the heterogeneous Cirriphyllum
where it was placed by A. J. Grout (1898). Phylogenetic analysis of M. Ignatov
and S. Huttunen (2002) confirmed the independent status of this genus, which
is moreover probably one of the most isolated and ancient in the family. 1. Bryoandersonia illecebra
(Hedwig) H. Robinson, Bryologist 65:
139. 1962 [1963] Hypnum illecebrum Hedwig,
Sp. Musc. Frond. 252. 66: figs.
1--2. 1801; Cirriphyllum boscii (Schwägrichen)
Grout Stems to 10(--15) cm, branches to 15(--30)
mm. Stem leaves 1.4--2.2 x 1--1.4 mm; mid leaf cells (30--)40 /um.--55(--70)
x 5--7 Seta 1.3--2.3 cm. Capsule ca. 1.5 mm. Soil in
forest, on landslides and among moderately dense grasses in meadow and lawns,
also rocks and tree bases; 10--920 m; Ont.; Ala., Ark.,
Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Md., Mass.,
Mich., Miss., Mo., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn.,
Tex., Va., W.Va. Bryoandersonia is a locally common species in
the eastern North America, especially in more southern states, and it can be
expected in northeastern Mexico. The species is easy to recognize by very
concave leaves and associated julaceous shoots. In exposed habitats the plant
often grows as a dense cluster of evenly julaceous shoots. In more mesic
environments the stem is more elongate, with spaced branches that have
strongly concave leaves only near their ends, while proximally, in older
parts of plants leaves are ovate-triangular and only slightly concave. In its
growth pattern Bryoandersonia is
much like Myuroclada, a monotypic
genus widespread in East Asia and found in North America only in Alaska;
thus, confusing them is not likely. Pseudoscleropodium
purum has some similarity with Bryoandersonia
when depauparate, but differs, however, in regular pinnate branching,
growth in rather dense tufts, and only slightly serrate distal leaf margins.
Sporophytes are rare in Bryoandersonia. OTHER
REFERENCES: Grout, A. J.
1898. A revision of the North American Eurhynchia. Bull. Torrey Bot. Club 25:
221--256. Ignatov,
M. S. and S. Huttunen 2002 [2003]. Brachytheciaceae (Bryophyta)---a family of
sibling genera. Arctoa 11: 245--296. |
