Dicranum fuscescens

Turner

Muscol. Hibern. Spic., 60, plate 5, fig. 1. 1804,.

Treatment appears in FNA Volume 27. Treatment on page 411. Mentioned on page 400, 410, 412, 414, 417.

Plants light green to dark brownish green, dull, in loose tufts. Stems 1–6 (–18) cm, tomentose to scarcely tomentose with white or reddish-brown rhizoids. Leaves falcate-secund, often strongly so, sometimes somewhat sparse, distal leaves curled, proximal leaves with flexuose apices, slightly to strongly curled and crisped when dry, smooth, (3–) 4–7 (–10) × 0.6–1 mm, concave below, keeled above, from a lanceolate base to a gradually narrowed, fine, keeled subula; margins entire proximally, serrulate to strongly serrate in the distal half, sometimes nearly entire throughout; laminae 1-stratose and usually 2-stratose above on one or both margins, rarely some 2-stratose regions near costa; costa excurrent, 1/6–1/4 the width of the leaves at base, strong, terete, papillose to spinose distally on abaxial surface, occasionally almost smooth, sometimes extending to costa, abaxial ridges absent, with a row of guide cells, 2 well-developed stereid bands extending to distal part of leaf, adaxial epidermal layer of cells not differentiated, abaxial epidermal layer differentiated; cell-walls between lamina cells slightly bulging; leaf cells smooth to slightly papillose below on abaxial surface, papillose to spinose prorate above on abaxial surface; alar cells 2-stratose, strongly differentiated, sometimes extending to costa; proximal laminal cells elongate, pitted, (19–) 43–62 (–93) × (2–) 6–8 (–12) µm; distal laminal cells irregularly rounded, elliptic, short-rectangular to quadrate, not pitted, (7–) 9–23 (–36) × (4–) 8–12 (–14) µm. Sexual condition dioicous; male plants as large as females, growing intermixed, or in separate patches; interior perichaetial leaves abruptly short-acuminate, convolute-sheathing. Seta 1–3.5 cm, solitary, yellow, reddish yellow or brown. Capsule 1–3 mm, arcuate, inclined to horizontal, strumose, strongly furrowed when dry, somewhat contracted below mouth, dark-brown to reddish-brown; operculum 1–2 mm. Spores 14–24 µm.

Discussion

Varieties ca. 7 (2 in the flora).

l. Plants small, stems 1–6(–10) cm, usually densely foliate; leaf margins serrulate to strongly serrate in distal half; costa papillose to spinose distally on abaxial surface; distal laminal cells short-rectangular to quadrate, mostly 18–23 µm long; seta mostly shorter than 2.5 cm

15a. Dicranum fuscescens var. fuscescens

Selected References

None.

Key

1 Plants small, stems 1-6(-10) cm, usually densely foliate; leaf margins serrulate to strongly serrate in distal half; costa papillose to spinose distally on abaxial surface; distal laminal cells short-rectangular to quadrate, mostly 18-23 µm long; seta mostly shorter than 2.5 cm Dicranum fuscescens var. fuscescens
1 Plants large, stems 8-18 cm, sparsely foliate; leaf margins nearly entire; costa almost smooth on abaxial surface; distal laminal cells irregularly rounded, elliptic or short- rectangular, mostly 9-19 µm long; seta usually 2.5 cm long or more Dicranum fuscescens var. flexicaule
... more about "Dicranum fuscescens"
persistent +  and deciduous +
differentiated +
flexuose +
Robert R. Ireland Jr. +
Turner +
short to long +
differentiated +
narrowed +  and lanceolate +
microphyllous +
pseudomonoicous +, dioicous +, autoicous +  and sexual +
flagelliform +  and terete +
reproduction +  and asexual +
cucullate +
dark-brown +  and reddish-brown +
arcuate +  and straight +
inclined +  and horizontal +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
generally orange +  and brown +
specialized +
papillose +  and mammillose +
pseudomonoicous +, dioicous +  and sexual +
inflated +
differentiated +
1/6 +  and 1/4 +
papillose +
dioicous +  and sexual +
spreading +, erect-patent +  and erect-appressed +
smooth +  and rugose +
North America +, Europe +  and Asia +
reddish-brown +  and pitted-striolate +
2-stratose +  and 1-stratose +
enlarged +
falcate-secund +
sometimes abaxially +  and smooth +
smooth +  and slightly papillose +
acuminate +, ovate +  and lanceolate +
entire +  and serrate +
serrulate to strongly +
arcuate +  and straight +
long-rostrate +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
nonpitted +  and pitted +
toothed +  and forked +
short-acuminate +, concave +  and ovate +
pitted-striolate +
16 +  and single +
papillose +  and striolate +
undifferentiated +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Muscol. Hibern. Spic., +
reddish-brown +  and white +
smooth +  and papillose +
1 +  and 2 +
well-developed +
brown;reddish yellow;yellow +
flexuose +  and straight +
0 +  and 6 +
elongate +
1 cm10 mm <br />0.01 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
1/3 +  and 1/2 +
spherical +
1 cm10 mm <br />0.01 m <br /> (6 cm60 mm <br />0.06 m <br />) +
superficial +
Dicranum fuscescens +
Dicranum +
species +
deciduous +
lanceolate +
green +, light green +  and dark brownish +