Lycopodium annotinum L.
Bristly club-moss, stiff, or interrupted club-moss, lycopode innovant.
Lycopodiaceae, club-moss family.
Sp. Pl. 2: 1103. 1753.
Plants not caespitose; creeping stems mostly above ground, up to one metre long or more with upright groups of branching stems. Roots pallid-brown. Ground-level or under-ground stems horizontal; rhizomatous; elongate, or compact. Scales absent. Aerial stems erect; circular or oval in cross-section; with 0 ridges; glabrous. Branches yellowish (green). Leaves distributed along the stems; alternate; evergreen (stiff and bristly). Petioles absent. Leaf bases truncate. Blades 2–7 mm long; 0.8–1.2 mm wide; spreading from the vertical, or divaricate, or reflexed; leathery; straight, or somewhat curled (particularly along horizontal stems, but without specialized leaf bases, a contrast with Diphasiastrum alpinum); linear, or elliptic; flat; with inconspicuous veins; adaxial surface glabrous. Blades abaxial surface glabrous. Plants reproducing by spores borne in sporangia. Sporangia in terminal cone-like structures.
Distribution. Arctic Islands: Baffin.
Ecology and habitat. Substrates, tundra (often in heathy areas or herb mats, (Porsild 1957)); imperfectly drained moist areas (sunny places); non-calcareous rocks (granite or gneiss); gravel, sand, till; with low organic content.
Notes. This widespread common club-moss has been divided into various forms or varieties some of which have been treated as species. Present evidence supports the hypothesis that these are environmentally induced forms, the most distinctive of which has been called Lycopodium annotinum var. alpestre C. Hartman, with very leathery, appressed leaves only 2.5–6 mm long, and with entire mrgins. Plants intermediate between this and L. annontinum var. annotinum are considered to be a form that has been called var. pungens (Bachelot de la Pylie) Desvaux. This is an invalid name. If a variety is worth recognising, plants found in the Arctic Islands are var. alpestre (Wagner and Bieitel, 1993). Leaf lengths measured for specimens from the Canadian Arctic Archipelago ranged from 2–7 mm long, consistent with the range given for this variety.
In striking contrast to Diaphasiastrum, and Huperzia interspecific hybridization is practicially unknown in Lycopodium.
Illustrations. • plants in southern habitat. Relatively lush, non-arctic plants growing under a large tree. The leaves at the base of the plants are deep green. The strobili, cone-like structures bearing sporangia are pale yellow-green at the tips of the branches. CMN Photo-Library S84–5638. • surface view of plants. A dense stand of plants in Godhaven (Red River), Greenland. Left, the leaves at the base of the plants are deep green. The young unopened cone-like structures bearing sporangia are pale yellow-green at the tips of the branches. Right, the brownish-yellow cone-like tips of the branches have opened and shed the spores contained in the sporangia. CMN Photo-Library S78–456. Photograph by Mildred and Raymond D. Wood. • Close-up of plants. Plants approximately 15 cm high with dark green leaves at the base and pale yellow-green, cone-like strobilii on the tips of the branches. CMN Photo-Library S84–5638. • Close-up of young cone. Left, young fertile stobilus, or cone-like organ, with yellow sporangia just visiible in the in the axils of the lower sphorphylls. Right, sterile stem that has longer leaves.. Photo Library images S84–5636. • Close-up of old cones. Cone-like strobili that has opened to reveal sporangia borne in the axils of the leaves. Greenland, Disko. CAN 4701. • Leaf morphology. Contrasting leaf morphology in the three arctic species in the Lycopodiaceae. A. Diphasiastrum alpinum. Leaves of ultimate branches strictly four ranked, decussate, with every pair decurrent on the stem as a pair of flanges, each flange continuous with one margin of the leaf. B. Lycopodium annotinum. Leaves crowded in eight ranks tending to be subverticillate with four rows of each pseudo-whorl spreading from the stem. C. Huperzia selago, left a vegetative leaf; right a sporophyll leaf. • Arctic Island Distribution.
Cite this publication as: S.G. Aiken, M.C. LeBlanc, and M.J. Dallwitz 2000 onwards. Pteridophytes of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval.’ Version: 23rd February 2001. http://www.mun.ca/biology/delta/arcticf/’. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993, 1995, 2000) , and Aiken, Dallwitz et al. (1999) should also be cited (see References).
