Timmia norvegica var. excurrens

Bryhn

Bryoph. Itin. Pol. Norv., 121. 1906,.

Synonyms: Timmia comata Timmia norvegica var. comata (Lindberg & Arnell) H. A. Crum
Treatment appears in FNA Volume 27. Treatment on page 169. Mentioned on page 168.

Plants generally smaller and more delicate than those of var. norvegica. Leaves 2–6 mm, 0.5–0.6 mm wide at mid-limb; cells of mid-limb lamina 6–10(–11) × 6–9(–10) µm; costa excurrent, smooth on abaxial surface of sheath, smooth or slightly papillose on abaxial surface of the limb, with one–several teeth at back near the apex; base of costa pale and not strongly attached to the stem; stem tips often with loose deciduous clusters of almost linear leaves (ca. 3 × 0.1–0.2 mm).


Habitat: Calcareous areas, often on shaded limestone cliffs near rivers in Arctic and boreal regions, intermixed with other mosses, including other taxa of Timmia
Elevation: low to moderate elevations (0-1500 m)

Distribution

V27 215-distribution-map.gif

Greenland, Nfld. and Labr. (Nfld.), N.W.T., Nunavut, N.S., Que., Yukon, Alaska, Eurasia (Scandinavia, Switzerland, Poland, Russia), Atlantic Islands (Iceland).

Discussion

Variety excurrens is known also as a Quaternary subfossil from New York and Vermont. Variety excurrens is not known to occur with sporophytes, but the deciduous leaves no doubt act as vegetative propagules.

Selected References

None.

Lower Taxa

None.
Guy R. Brassard +
Greenland +, Nfld. and Labr. (Nfld.) +, N.W.T. +, Nunavut +, N.S. +, Que. +, Yukon +, Alaska +, Eurasia (Scandinavia +, Switzerland +, Poland +, Russia) +  and Atlantic Islands (Iceland). +
low to moderate elevations (0-1500 m) +
Calcareous areas, often on shaded limestone cliffs near rivers in Arctic and boreal regions, intermixed with other mosses, including other taxa of Timmia +
Bryoph. Itin. Pol. Norv., +
Timmia comata +  and Timmia norvegica var. comata +
Timmia norvegica var. excurrens +
Timmia norvegica +
variety +