Pleuroziopsis ruthenica

(Weinmann) Kindberg ex E. Britton

Bryologist 9: 39. 1906.

Illustrated
Basionym: Hypnum ruthenicum Weinmann Bull. Soc. Imp. Naturalistes Moscou 18: 485. 1845
Synonyms: Girgensohnia ruthenica (Weinmann) Kindberg
Treatment appears in FNA Volume 28. Treatment on page 513. Mentioned on page 318, 514.

Plants light green, frondose-dendroid. Stems with primary-stems stoloniferous, branches 1.5–3 cm, attenuate, branchlets 4–7 mm, attenuate; lamellae apical cells round, elliptic, square, or rectangular. Stem-leaves clasping, ovate, smooth or wrinkled; base long-decurrent, 1-stratose; apex apiculate or obtuse to acute; medial laminal cells vermicular, 40–81 × 5–7 µm. Proximal branch leaves gradually grading distally into leaves similar to branchlet leaves; median branchlet leaves plicate; base long-decurrent; margins plane or narrowly recurved near base, serrate to entire proximally, irregularly and strongly toothed to serrate distally; apex broadly acute; medial laminal cells 28–45 × 5–7 µm. Sexual condition dioicous; archegonial and antheridial plants similar, perigonial and perichaetial buds on stem near branches; perigonial leaves broadly ovate, acute; perichaetial leaves ovate, apex acute to acuminate. Seta smooth. Capsule red, not contracted below mouth. Calyptra cucullate, covering 1/2 capsule.


Habitat: Humus on ground or logs along creeks and rivers, moist, shaded habitats
Elevation: low to moderate elevations (10-600 m)

Distribution

V28 798-distribution-map.gif

B.C., Alaska, Wash., e Asia

Discussion

Pleuroziopsis ruthenica is a distinctive species, somewhat reminiscent of Climacium; both have erect secondary stems arising from a creeping primary stem and occur in wet habitats. Pleuroziopsis is lighter green and more slender in appearance, with a frondose-dendroid habit, an ovoid, arcuate, cernuous capsule with a hypnaceous peristome and exostome teeth with fine cross striolations; Climacium has a coarser dendroid habit and a cylindric, straight, erect capsule with narrow, densely papillose endostome segments. Another important feature distinguishing Pleuroziopsis from Climacium is the nature of branching. In Pleuroziopsis, the plants are erect from a creeping primary stem, as in Climacium, but they are also frondose-dendroid, that is, they are flattened and the secondary and tertiary branches are divided, often several times, so the plants are noticeably frondose. In Climacium, the plants are not flattened; the branches arise around the distal end of the erect secondary stem and seldom, if ever, produce branchlets.

Selected References

None.

Lower Taxa

None.
... more about "Pleuroziopsis ruthenica"
acute;acuminate +
rectangular +, square +, elliptic +  and round +
Robert R. Ireland Jr. +
(Weinmann) Kindberg ex E. Britton +
long-decurrent +
Hypnum ruthenicum +
erect-spreading +
attenuate +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
cucullate +
3 cm30 mm <br />0.03 m <br /> (?) +
1 cm10 mm <br />0.01 m <br /> (?) +
inflated +
strong +  and weak +
B.C. +, Alaska +, Wash. +  and e Asia +
low to moderate elevations (10-600 m) +
Humus on ground or logs along creeks and rivers, moist, shaded habitats +
strongly toothed +  and serrate +
dioicous +  and sexual +
acute +  and ovate +
not evident +
much-branched +
reddish-brown +  and whitish +
papillose +
2-pinnate +  and pinnate +
orange;red +
elongate +
1.5 cm15 mm <br />0.015 m <br /> (?) +
Illustrated +
germinating +
wrinkled +  and smooth +
1.5mm;2.5mm +
Girgensohnia ruthenica +
Pleuroziopsis ruthenica +
Pleuroziopsis +
species +
medium-sized;large +