Russia Flora: Plant up to 13-15 cm tall, darkish green. Creeping stems submerged in the substrate, with reduced, sparsely arranged phyllodia. Vertical branches weakly branched in the lower part. Phyllodia lanceolate, 4-5 mm long, 0.6-0.8 mm wide, gradually narrowed into a sharp point, entire-margined, slightly appressed, obliquely spreading or almost protruding. In some areas, phyllodia are smaller in size and more appressed to the stem, making branches appear bead-like constricted, with "pinches." Strobiloids sessile, solitary, up to 2 cm long. Sporophylloids triangular-deltoid, up to 4 mm long, including the suddenly narrowed awn-like ending up to 1.5 mm long, with a wide membranous-fringed edge. Sporangium elongated-reniform, 0.6 mm long.

Chukotka, Anadyr, Anadyr-Penzhina, Koryak, Kolyma, Okhotsk, Aldan, Nyukzha, Kamchatka, Northern Sakhalin, Upper Zeya, Lower Zeya, Amur, Ussuri, Southern Sakhalin (Fig. 4). — Waterlogged open larch woodlands, dwarf cedar and alder formations, sphagnum bogs in the north of the taiga zone and in the forest-tundra, in the south — in mountains; in lowlands, in mountain forest and subalpine belts. VIII-IX. — General distribution: European part, Western and Eastern Siberia; Scandinavia, Mongolia, Japan-China, North America. — Described from Iceland.

Note: A species closely related to L. annotinum L., of which it is a more northern derivative.