Dicranum leioneuron

Kindberg

Bull. Torrey Bot. Club 16: 92. 1889,.

Treatment appears in FNA Volume 27. Treatment on page 404. Mentioned on page 399, 405.

Plants in loose tufts, yellowish green, glossy. Stems 5–8 cm, scarcely tomentose with whitish to reddish-brown rhizoids. Leaves erect or spreading, distal leaves with twisted apices when dry, slightly rugose, (3.5–) 5–7 (–8) × 1–1.5 mm, concave proximally, tubulose distally, from an ovatelanceolate base to a long or short subula, broadly acute, some leaves short, ovate, somewhat obtuse, forming julaceous regions, in the middle or basal part of the stems; margins not or slightly serrate in the distal part, somewhat involute in the middle part; laminae 1-stratose; costa ending before the apex, 1/13–1/8 the width of the leaves at base, smooth or sometimes the distal part with two weakly serrated ridges on abaxial surface, row of guide cells, two stereid bands, adaxial and abaxial epidermal layers of cells not differentiated or sometimes a few cells in the abaxial layer differentiated; cell-walls between lamina cells not bulging; leaf cells smooth; alar cells 2-stratose, differentiated, not extending to costa; proximal laminal cells elongate-sinuose, pitted, (42–) 75–87 (–107) × (7–) 8–10 (–16) µm; distal laminal cells short, sinuose, pitted, (16–) 30–65 (–79) × (7–) 9–13 (–16) µm. Sexual condition pseudomonoicous; dwarf males on rhizoids of female plants; interior perichaetial leaves abruptly long-acuminate, convolute-sheathing. Seta 2–4 cm, solitary, yellow, yellowish-brown or reddish yellow. Capsule 2–3.5 mm, arcuate, inclined, smooth, ± furrowed when dry, yellow to yellowish-brown; operculum 1.5–2 mm. Spores 14–24 µm.


Phenology: Capsules mature spring.
Habitat: Primarily in hummocks in ombrotrophic and oligotrophic peatlands
Elevation: 10-1100 m

Distribution

V27 571-distribution-map.gif

B.C., N.B., Nfld. and Labr. (Nfld.), N.W.T., N.S., Ont., P.E.I., Que., Yukon, Alaska, nw Europe

Discussion

Dicranum leioneuron is apparently closely related to D. bonjeanii. It is best distinguished by the subulate leaves with twisted apices when dry, the usual occurrence of julaceous stem portions with broad, short, concave, and somewhat obtuse leaves in contrast to the longer, narrower, subulate, and acute leaves of the other stem portions. Its occurrence only in hummocks in peatlands also is a clue to its identity. The plants rarely produce sporophytes but in any event they cannot be distinguished from those of the other species in section Dicranum. The species probably occurs in peatlands in northeastern United States and it should be looked for in that region.

Selected References

None.

Lower Taxa

None.

... more about "Dicranum leioneuron"
persistent +  and deciduous +
differentiated +
0.7 cm7 mm <br />0.007 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
1mm +  and 1.5mm +
Robert R. Ireland Jr. +
Kindberg +
short to long +
differentiated +
ovatelanceolate +
microphyllous +
pseudomonoicous +, dioicous +, autoicous +  and sexual +
flagelliform +  and terete +
reproduction +  and asexual +
cucullate +
yellow +  and yellowish-brown +
arcuate +  and straight +
cylindric +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
generally orange +  and brown +
specialized +
papillose +  and mammillose +
pseudomonoicous +, dioicous +  and sexual +
inflated +
differentiated +
toothed +
pseudomonoicous +  and sexual +
spreading +, erect-patent +  and erect-appressed +
smooth +  and rugose +
B.C. +, N.B. +, Nfld. and Labr. (Nfld.) +, N.W.T. +, N.S. +, Ont. +, P.E.I. +, Que. +, Yukon +, Alaska +  and nw Europe +
reddish-brown +  and pitted-striolate +
10-1100 m +
Primarily in hummocks in ombrotrophic and oligotrophic peatlands +
enlarged +
falcate-secund +
papillose +, mammillose +, nonpitted +  and pitted +
obtuse +  and ovate +
arcuate +  and straight +
long-rostrate +
0.15 cm1.5 mm <br />0.0015 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 +
Capsules mature spring. +
undifferentiated +
Bull. Torrey Bot. Club +
whitish +  and reddish-brown +
smooth +  and papillose +
well-developed +
reddish yellow;yellowish-brown;yellow +
flexuose +  and straight +
0 +  and 6 +
elongate +
2 cm20 mm <br />0.02 m <br /> (4 cm40 mm <br />0.04 m <br />) +
1/3 +  and 1/2 +
spherical +
5 cm50 mm <br />0.05 m <br /> (8 cm80 mm <br />0.08 m <br />) +
superficial +
Dicranum leioneuron +
Dicranum +
species +
deciduous +
lanceolate +