BFNA Title: Conostomum
1. Conostomum Swartz in F. Weber & D. Mohr, Naturh. Reise Schwedens 122. 1804 * [Latin conos, cone-shaped, and stoma, opening]
Plants in dense, glaucous or yellow green tufts. Stems 0.5--1(--8) cm, brown and radiculose below, rhizoids smooth. Leaves lanceolate, acuminate or rarely blunt, keeled, imbricate, appressed dry or moist, in 5 distinct rows; margins plane or narrowly revolute in distal 1/2--2/3, serrulate to subentire; costa percurrent to excurrent, sometimes subpercurrent in proximal leaves, mammillose-toothed abaxially; distal cells rectangular or short-rhomboidal, firm-walled, smooth or mammillose at distal ends on both surfaces; proximal cells rectangular, laxer than those distally; alar cells undifferentiated. Specialized asexual reproduction unknown. Sexual condition dioicous or autoicous, perigonia large, cupulate or gemmiform with subclavate paraphyses; perichaetial leaves larger than stem leaves. Seta solitary, elongate, variable in length, smooth. Capsule erect to inclined, slightly asymmetric, broadly obovoid to oblong from a short swollen neck, wrinkled and furrowed when dry; annulus lacking; operculum conic, stoutly beaked, usually oblique; peristome single or, rarely, lacking, teeth linear-lanceolate, smooth to somewhat papillose at base, narrowly bordered, fused at the tips forming a perforated cone. Spores large, nearly smooth to coarsely papillose.
Species 7--15 (1 in the flora); North America; Mexico; West Indies; South America; Europe; Asia; Africa; Pacific Islands.
SELECTED REFERENCES Crum, H.A. and L.E. Anderson. 1981. Mosses of Eastern North America. Vol. 1, pp. 641-642. New York. Flowers, S. 1935. Conostomum. In: A.J. Grout, ed. 1935. Moss Flora of North America 2(3): 154. Newfane, Vermont. Frahm, J.-P., Heike Borner, Nikola Streiber, Bernd Wallau and Stefan Weitkus. Revision der Gattung Conostomum (Musci; Bartramiaceae). Trop. Bryol. 12: 97--114. Lawton, E. 1971. Moss Flora of the Pacific Northwest. Nichinan.
1. Conostomum tetragonum (Hedwig) Lindberg, Oefv. K. Ak. Forh. 20: 392. 1863
Mnium tetragonum Hedwig, Spec. Musc. 73: 1801; Conostomum boreale Swartz
Plants in dense, glaucous, sometimes yellowish tufts. Stems simple or forked, erect, 0.5--3 cm. Leaves narrowly lanceolate, not clasping, 1--1.5 mm, stiffly erect in 5 rows; margins slightly revolute in distal half, serrulate near apex; costa stout, subpercurrent at least in proximal leaves to excurrent, rough abaxially distally; distal laminal cells rectangular to short-rhomboidal, thick-walled, 24--30 × 7--8 µm, smooth or mamillose from distal ends. Sexual condition dioicous, perichaetial leaves subulate from an ovate base, 2--2.5 mm. Seta 8--25 mm, yellowish red to brown, flexuose. Capsule ovoid with a short neck, somewhat furrowed when dry, 2--2.5 mm; operculum obliquely rostrate; peristome teeth elongate lanceolate, reddish orange to dark brown with a narrow yellow border, smooth throughout or finely papillose at base, perforate and connate at apex. Spores spherical to reniform, 41--52 µm, coarsely papillose.
Capsules mature June--Aug. Thin soil, cliff ledges or among boulders, often on waterlogged soils of late season snow melt; 0--2200 m; Greenland; Alta, B.C., N.B., Nfld., N.W.T., Nun., Que., Yukon; Alaska, Maine, Mont., Oreg., N.H., N.Y., Wash.; Europe; c. and n Asia.
This species is easily recognized by the glaucous, stiffly erect leaves in 5 rows and the apically fused peristome teeth. Philonotis seriata (known only from Greenland in the flora area), shares the pentastichous leaf arrangement, but the leaf cells of Philonotis seriata are prorulose at the proximal ends and the peristome teeth are free.