Family: Leskeaceae |
Plants: small to large, in thin to thick mats, green, yellow-green, orange-green, or gold-green, brown with age. Stems: irregularly branched; paraphyllia many, few on older stems, or sometimes absent, filamentous to foliose, cells smooth or prorulose; rhizoids in clusters arising from base of stem leaves. Stem: and branch leaves similar. Stem: leaves appressed to julaceous when dry, erect-spreading when moist, ovate to lanceolate, weakly to strongly plicate on either side of costa; margins recurved proximally, entire to serrulate distally, limbidium present or absent; apex abruptly acute to long-acuminate, hair-point present or absent; costa single, moderately strong, 2/3 leaf length to subpercurrent, opaque, not or weakly sinuate; alar cells transversely elongate, quadrate, or short-rectangular; proximal laminal cells similar to medial cells, usually shorter, 1–4:1, walls pitted; medial cells quadrate to elongate-rhomboidal, 1–4:1, 1-papillose to prorate, walls firm to thin; apical cells elongate. : Specialized asexual reproduction absent. Sexual: condition dioicous; perichaetial leaves pale translucent, erect when moist, longer, apex more acuminate, costa percurrent. Seta: 0.8–1.2 cm. Capsule: inclined, cylindric, asymmetric or symmetric; annulus absent; operculum smooth conic (conic-apiculate in P. baileyi); peristome well developed; exostome teeth lanceolate, striate to papillose; endostome basal membrane high, segments slender-lanceolate to filiform, cilia well developed to short and rudimentary. Spores: 10–28 µm, papillose. North America, Eurasia, Atlantic Islands (Iceland). Species ca. 12 (8 in the flora). Pseudoleskea are Northern Hemisphere species of montane to alpine regions found on rock and soil, typically in cool to cold climates. Pseudoleskea differs from Lescuraea in the shorter and mostly thicker-walled laminal cells and in the mostly perfect hypnoid peristome, showing some reduction in a few species. The stem leaves are weakly to strongly concave; the capsule is red to red-brown with bordered exostome teeth and 1–3 endostome cilia. J. R. Rohrer (1986) compared differences among the taxa. Pseudoleskea baileyi does not belong in the genus and appears to be closest morphologically to the eastern Asian Rigodiadelphus Dixon (M. U. Krieger 2002); it is included here for completeness. |