Didymodon rigidulus var. icmadophilus

(Schimper ex Müller Hal.) R. H. Zander

Cryptog. Bryol. Lichénol. 2: 394. 1981,.

Basionym: Barbula icmadophila (Schimper ex Müller Hal.) K. Saito Syn. Musc. Frond. 1: 614. 1849
Synonyms: Barbula acuta var. icmadophila (Schimper ex Müller Hal.) H. A. Crum Didymodon acutus var. icmadophilus (Schimper ex Müller Hal.) R. H. Zander Didymodon icmadophilus
Treatment appears in FNA Volume 27. Treatment on page 545. Mentioned on page 542, 544, 546, 547.

Stem leaves appressed to weakly spreading when dry, long-lanceolate, abruptly broadened, oval; costa usually long-excurrent as a straight or flexuose, often fragile subula; proximal cells usually quadrate; distal laminal cells usually smooth, quadrate, with angular lumens, distal lamina rarely 2-stratose in patches; gemmae very rare. Peristome teeth short and straight to long and twisted.


Phenology: Capsules mature summer–fall.
Habitat: Marble, limestone, sandstone, ledges, soil, sand of beaches and dunes, frost boil, old musk ox feces
Elevation: low to high elevations (40-2800 m)

Distribution

V27 780-distribution-map.gif

Greenland, Alta., B.C., Man., Nfld. and Labr. (Nfld.), Nunavut, Que., Yukon, Alaska, Calif., Colo., Mont., Nev., N.Y., S.Dak., Tenn., Tex., Mexico, Central America, South America, Europe, Asia, Atlantic Islands (Iceland).

Discussion

Variety icmadophilus is similar to var. gracilis in general aspect but the leaf apices are usually hairlike and protuberant, the distal laminal cells are usually smooth and their lumens usually angular. It is common on the North American Plains, where it may occur in association with Didymodon fallax. The former plant is green in young parts, sometimes with a blue-black cast, but commonly red basally, and has boat-shaped elongate, erect leaves that are only slightly incurved when dry, laminal cells smooth and costa excurrent and often flexuose. Didymodon fallax has light green to reddish green color throughout and triangular leaves that are often incurved or even catenulate when dry, costa percurrent and leaves papillose. Variety icmadophilus is rare in the East: Tennessee, Sharp 34606, TENN, and New York, Drummond 120, NY, are apparently this variety.

Selected References

None.

Lower Taxa

None.
Richard H. Zander +
(Schimper ex Müller Hal.) R. H. Zander +
Barbula icmadophila +
Greenland +, Alta. +, B.C. +, Man. +, Nfld. and Labr. (Nfld.) +, Nunavut +, Que. +, Yukon +, Alaska +, Calif. +, Colo. +, Mont. +, Nev. +, N.Y. +, S.Dak. +, Tenn. +, Tex. +, Mexico +, Central America +, South America +, Europe +, Asia +  and Atlantic Islands (Iceland). +
low to high elevations (40-2800 m) +
Marble, limestone, sandstone, ledges, soil, sand of beaches and dunes, frost boil, old musk ox feces +
Capsules mature summer–fall. +
Cryptog. Bryol. Lichénol. +
Barbula acuta var. icmadophila +, Didymodon acutus var. icmadophilus +  and Didymodon icmadophilus +
Didymodon rigidulus var. icmadophilus +
Didymodon rigidulus +
variety +