Didymodon rigidulus var. ditrichoides

(Brotherus) R. H. Zander

Phytologia 41: 20. 1978,.

Basionym: Barbula ditrichoides Sitzungsber. Akad. Wiss. Wien, Math.-Naturwiss. Kl., Abt. 1, 133: 566. 1924
Synonyms: Didymodon acutus var. ditrichoides (Brotherus) R. H. Zander
Treatment appears in FNA Volume 27. Treatment on page 544. Mentioned on page 545, 558.

Stem-leaves strongly appressed when dry, linear-lanceolate, base broadened, ovate to oblong; costa long-excurrent, sharp; proximal cells shortrectangular; distal laminal cells smooth, quadrate to shortrectangular, with quadrate to shortrectangular lumens, distal lamina 1-stratose; gemmae absent. Peristome not seen.


Habitat: Limestone outcrops, dry tundra
Elevation: moderate elevations (1200 m)

Distribution

V27 778-distribution-map.gif

N.W.T., Asia (China), Atlantic Islands (Iceland)

Discussion

Variety ditrichoides is a highly reduced, flagellate form of var. icmadophilus but with a distinctive appearance. It is disjunct from montane China (Chen P. C. 1941) to a single locality in the flora area (Northwest Territories, Mackenzie District, Nahanni Range, 61º43’N, 123º20’W, D. Vitt, 1977, BUF). The olive coloration and general appearance is similar to D. leskeoides but the plant is somewhat smaller and the alar auricles are lacking.

Selected References

None.

Lower Taxa

None.

"um" is not declared as a valid unit of measurement for this property."um" is not declared as a valid unit of measurement for this property.

quadrate +  and elongate +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
channeled +, concave +  and long-triangular +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
of 1-2 rows +  and differentiated +
Acute (?) +  and Subulate (?) +
Richard H. Zander +
(Brotherus) R. H. Zander +
weak +  and strong +
ovate +  and crescent--shaped +
papillose +  and smooth +
usually slightly wider +
ovate;oblong +
differentiated +
broadened +
Barbula ditrichoides +
obovoid +
cucullate +
stegocarpous +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
monoicous +, dioicous +  and sexual +
flat to bulging +
thin;thick +
1 (?) +  and 10 (?) +
hexagonal +
differentiated +
tomentose +  and bare +
long-excurrent +
widened +
quadrate +  and rectangular +
occasionally weakly dentate or crenulate +  and entire +
subquadrate;hexagonal or rounded-angular occasionally shortly rectangular or rhomboid +
N.W.T. +, Asia (China) +  and Atlantic Islands (Iceland) +
moderate elevations (1200 m) +
differentiated +
multicellular +
occasional +
Ovate (?) +  and Elliptic (?) +
Limestone outcrops, dry tundra +
yellow +  and orange-red or red +
long-ligulate +  and monomorphic +
0.17 cm1.7 mm <br />0.0017 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.17 cm1.7 mm <br />0.0017 m <br />) +
not +, spreading +, appressed-incurved +  and weakly spreading +
channeled;ovatelanceolate;keeled +
ovate +, keeled +  and curled +
reduced +
specialized +
dioicous +  and sexual +
oval +  and roundedquadrate +
short-conic;long-conic +
photosynthetic +
lateral +  and terminal +
lateral +  and terminal +
twisted +, cleft +  and perforated +
red-orange +  and yellow +
0-740 um +  and rudimentary +
0-740 um +  and occasionally absent +
0-740 um-triangular +  and long-triangular +
1 (?) +  and 2 (?) +
straight +
yellowish;reddish-brown +
elongate +
0.7 cm7 mm <br />0.007 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
2 +  and 1 +
yellow +, red-orange +, red +  and laminal +
linear-lanceolate +
rounded-triangular +  and rounded-pentagonal +
0 cm0 mm <br />0 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Didymodon acutus var. ditrichoides +
Didymodon rigidulus var. ditrichoides +
Didymodon rigidulus +
variety +
elliptic;cylindric +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
rudimentary +
red +  and yellow +
specialized +
thin +  and evenly thickened +
stemless +  and perigoniate +