Rhizomnium glabrescens

(Kindberg) T. J. Koponen

Ann. Bot. Fenn. 5: 143. 1968.

EndemicIllustrated
Basionym: Mnium glabrescens Kindberg Ottawa Naturalist 7: 18. 1893
Treatment appears in FNA Volume 28. Treatment on page 239. Mentioned on page 238.

Plants (1–) 2–3 cm. Stems reddish-brown, brown, or black when old; micronemata absent. Leaves green to dark green, slightly contorted and somewhat undulate when dry, obovate or elliptic, (2.5–) 4.5–6 mm; margins green or sometimes reddish or brownish, 2–4-stratose; apex rounded or occasionally obtuse or retuse, short-apiculate; costa subpercurrent or percurrent; medial laminal cells short-elongate, sometimes elongate or ± isodiametric, (35–) 45–60 (–70) µm, weakly or not collenchymatous, walls pitted; marginal cells linear, in 3–4 (–5) rows. Sexual condition dioicous. Seta (2–) 3–5 cm. Capsule oblong or cylindric, 3–4.5 mm; operculum conic-apiculate or conic-rostrate; exostome greenish yellow, lamellae 18+. Spores 30–45 µm.


Phenology: Capsules mature summer.
Habitat: Forests, logs or tree bases, moist soil near streams, thin soil over shaded rock
Elevation: low to moderate elevations

Distribution

V28 382-distribution-map.gif

B.C., Alaska, Calif., Idaho, Oreg., Wash.

Discussion

Rhizomnium glabrescens, common in coastal forests along the west coast, is small but distinctive. Male plants are characterized by rosettes of large leaves at the tops of the nearly naked stems. Small, scalelike leaves are present along the stem below the upper rosette. The stems of female and sterile stems have relatively large leaves. Sterile stems often arch, resembling those of Plagiomnium, but are always the same length or shorter than the fertile stems.

Selected References

None.

Lower Taxa

None.
... more about "Rhizomnium glabrescens"
blackish +, orange-yellow +, reddish-brown +, yellowish-brown +, yellowish green +, red +, brown +  and yellow +
Retuse (?) +, Obtuse (?) +  and Rounded (?) +
Terry T. McIntosh +  and Steven G. Newmaster +
(Kindberg) T. J. Koponen +
long-decurrent +
Mnium glabrescens +
cucullate +
yellowish-brown +  and yellow +
horizontal;pendent +
cylindric +  and oblong +
0.3 cm3 mm <br />0.003 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
undifferentiated +
2 (?) +  and 1 (?) +
nodulose +
subpercurrent +
toothed +
B.C. +, Alaska +, Calif. +, Idaho +, Oreg. +  and Wash. +
low to moderate elevations +
yellowish-brown +  and yellow +
greenish yellow +
lanceolate-acuminate +
Forests, logs or tree bases, moist soil near streams, thin soil over shaded rock +
crowded +  and distant +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
green +  and dark green +
elliptic +, obovate +  and undulate +
larger +  and small +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
brownish +, reddish +, sometimes +  and green +
dioicous +  and sexual +
rectangular +, rhomboidal +  and linear +
elongate +  and short-elongate +
conic-rostrate +  and conic-apiculate +
Capsules mature summer. +
Ann. Bot. Fenn. +
smaller +  and larger +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
pale +, orange +  and reddish-brown +
flexuose +  and straight to somewhat +
elongate +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
Endemic +  and Illustrated +
spheric +
not dendroid +  and simple +
black +, brown +  and reddish-brown +
arching +  and erect +
sinuate +
Rhizomnium glabrescens +
Rhizomnium +
species +
blunt +  and sharp +