Brachytheciastrum velutinum

(Hedwig) Ignatov & Huttunen

Arctoa 11: 260. 2003.

Illustrated
Basionym: Hypnum velutinum Hedwig Sp. Musc. Frond., 272. 1801
Treatment appears in FNA Volume 28. Treatment on page 412. Mentioned on page 409, 411, 413, 414, 416.
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Plants small, in loose or moderately dense tufts, green to yellowish or brownish. Stems to 4(–5) cm, creeping or ascending and erect, terete- to subcomplanate-foliate, not julaceous, regularly or irregularly pinnate, branches to 4(–6) mm, terete- or subcomplanate-foliate. Stem leaves erect to erect-spreading, densely to loosely arranged, falcate to circinate, ovate-lanceolate to lanceolate, not plicate or with 2 submarginal plicae, rarely with additional indistinct plicae, 1–1.8 × (0.1–)0.2–0.5(–0.6) mm; margins plane or recurved at base, serrate, serrulate, or subentire; apex gradually long-acuminate, acumen weakly spreading; costa to 40–70% leaf length, often thick distally, terminal spine present; alar cells subquadrate to short-rectangular, 8–12 × 10–15 µm, region small, of 4–8 × 4–6 cells, distinctly delimited; laminal cells linear, 45–140 × 4–7 µm; basal cells short-rectangular, 8–10 µm wide, region in 1 or 2 indistinctly delimited rows. Seta red-brown, 0.8–1.5 cm, smooth, rough, or rough proximally and smooth near capsule. Capsule horizontal, brown, dark red-brown with age, elongate, to 1.5 mm; endostome basal membrane 1/3–1/2 endostome length, cilia as long as segments. Spores 10–14(–15) µm.

Distribution

V28 639-distribution-map.gif

North America, Eurasia, n Africa, Atlantic Islands.

Discussion

Varieties 2 (2 in the flora).

Plants of Brachytheciastrum velutinum have less strongly plicate branch leaves than stem leaves.

Selected References

None.

Key

1 Setae rough throughout; branches subcomplanate-foliate; branch leaves ± falcate or occasionally straight; stem leaves 1-1.6 mm; plants green, sometimes yellowish or brownish; laminal cells 45-90(-125) × 5-7 µm; widespread. Brachytheciastrum velutinum var. velutinum
1 Setae slightly rough proximally and smooth near capsule, or smooth throughout; branches terete- or rarely subcomplanate-foliate; branch leaves straight; stem leaves 1.2-1.8 mm; plants green to golden brown; laminal cells (60-)80-140 × 4-5µm; w United States, Texas. Brachytheciastrum velutinum var. salicinum