Distichium

Bruch & Schimper

Bryol. Europ. 2: 153. 1846 ,.

Etymology: Greek distichos, in two rows, alluding to leaves
Treatment appears in FNA Volume 27. Treatment on page 448. Mentioned on page 443, 444.
Revision as of 22:34, 27 May 2020 by imported>Volume Importer

Plants slender, elongate, in dense tomentose tufts, yellowish green to dark green. Stems 1–6 cm, simple or branched; rhizoids from base to middle of stem forming a conspicuous tomentum. Leaves distichous, linear subula spreading from erect, whitish ovate-lanceolate or oblong sheathing base, margins plane to slightly incurved, becoming denticulate in subula particularly near the apex; costa excurrent, occupying most of subula, 1/4–1/3 width of leaf at base, subula roughened abaxially; lamina cells of sheathing base linear to oblong-linear, linear-flexuose or rectangular, becoming rectangular distally and quadrate to short-rectangular in subula. Specialized asexual reproduction unknown. Sexual condition autoicous, paroicous or synoicous; perigonia axillary, or on short branches proximal to perichaetium; perichaetial leaves not differentiated. Seta yellow-brown to reddish, elongate, erect. Capsule erect and symmetric or inclined and asymmetric, exserted, brown, cylindric to ovoid-cylindric, ± wrinkled when dry and empty; annulus of 2–3 rows of large, pale cells, deciduous; operculum conic, straight; peristome single, teeth16, variously split to near the base into 2(–3) minutely papillose filaments, teeth sometimes arranged in 8 groups of 2 teeth. Calyptra cucullate. Spores globose to ovoid, finely papillose.

Discussion

Species 14 (3 in the flora).

Distichium capillaceum var. curvatum Flowers was described as a probable hybrid between D. capillaceum and D. inclinatum, characterized by capsule cylindric and strongly curved, and spores 20–23 µm.

Selected References

None.

Key

1 Capsule erect, cylindric, straight to slightly arcuate, spores 15-25 µm. Distichium capillaceum
1 Capsule inclined, ovoid to oblong-ovoid, spores more than 25 µm > 2
2 Peristome with a yellowish to hyaline basal membrane uniting teeth into 8 separated groups each of 2 teeth. Distichium hagenii
2 Peristome of 16, evenly spaced, irregularly divided or perforate teeth. Distichium inclinatum