Platydictya minutissima

Plants thin, ± silky, green to brownish. Stems with branching angle wide, branches firmly attached; pseudoparaphyllia apparently absent; rhizoids below or at abaxial leaf insertion, redbrown, smooth. Leaves loosely spreading, 0.1–0.3 mm; base not narrowed to insertion; margins entire at insertion, serrulate elsewhere; alar cells scarcely differentiated; distal laminal cells elongate-rhomboidal, 3–6: 1. Specialized asexual reproduction absent. Sexual condition autoicous; perichaetial leaf margins coarsely dentate distally. Seta 0.4–0.9 cm. Capsule inclined, horizontal, or sometimes suberect, broadly oblong-ovoid, asymmetric, 0.4–0.5 mm, not contracted below mouth when dry, neck absent; stomata absent; annulus 1-seriate; operculum convex-conic, stoutly apiculate; exostome teeth yellowish; endostome cilia 1 or 2, well developed. Spores 8–13 µm.

Habitat: Moist, shaded rock (limestone, sandstone)
Elevation: low to moderate elevations

Que., Ark., Ind., Mass., N.J., N.Y., Ohio, Pa., Wis.

Discussion

Platydictya minutissima is rare and occurs in thin, rather silky mats. The leaves are somewhat remote, loosely spreading when dry, and serrulate except near the insertion; the laminal cells are elongate, and those in the alar regions are scarcely differentiated.

Selected References

None.

Lower Taxa