Plants typically small and slender, larger and compact in the Arctic, capitulum small to moderate-sized, often with a conspicuous terminal bud; green, yellowish brown to brown; without metallic lustre when dry. Stems pale green to straw-colored; superficial cortical with a large round pore in distal portion of cell free from cell wall. Stem leaves spatulate to broad-spatulate, 0.8-1.5(-2) mm, strongly lacerate across the broad apex and often part way down the margins, border scarcely to strongly broadened at base (0.25 width of base or less); hyaline cells rhomboid, efibrillose and often 1-2-septate. Branches not 5-ranked, quite terete, long, and slender Branch fascicles with 1- 2 spreading and 1-2 pendent branches. Branch leaves ovate to ovate-lanceolate; 1.1-1.5(-2) mm, slightly concave, straight; apex involute; margins entire; hyaline cells on convex surface with numerous pores along the commissures grading from small pores near leaf apex to large pores at base, concave surface with large round pores at leaf apex and along margins. Sexual condition often monoicous. Spores 20-27 µm, finely papillose on both surfaces; proximal laesura less than 0.5 spore radius.
Isotype for Sphagnum microphyllum Warnst.
Catalog Number: US
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Verification Degree: Card file verified by examination of alleged type specimen
Preparation: Pressed specimen
Collector(s): H. N. Bolander
Year Collected: 1864
Locality: California, United States, North America
Isotype: Warnstorf, C. F. 1891. Hedwigia. 30: 172.