Daltonia

• Authority

  Buck, William R. 1998. Pleurocarpous mosses of the West Indies. Mem. New York Bot. Gard. 82: 1-400.

• Family

  Daltoniaceae

• Scientific Name

  Daltonia

• Description

  Genus Description - Plants small, in often lustrous bright-green to golden, usually small tufts or scattered. Stems ± erect, simple or rarely forked, the branches not differentiated, evenly foliate; in cross-section with thick-walled cells surrounding large thin-walled cells, central strand none; rhizoids usually confined to bases of stems, smooth; pseudoparaphyllia none; axillary hairs (2-)3-celled, the basal 1 shortish, brown, the upper 2 somewhat longer and hyaline, sometimes light-brown, when of 2 cells the uppermost much longer than the basal one. Leaves isophyllous, usually densely foliate, sometimes contorted when dry, ± erect when moist, linear-lanceolate to ovate-lanceolate, symmetric, acuminate; margins with a border of several rows of narrow, elongate cells, usually broader below, entire to serrulate, plane or recurved; costa single, ending (V2-)5A the leaf length, well below apex; cells oval to rhomboidal to long-hexagonal, smooth, usually thick-walled, especially when short, becoming more elongate and mostly colored toward insertion; alar cells not differentiated. Asexual propagula sometimes clustered in leaf axils, elongate, uniseriate. Autoicous or synoicous. Perichaetia small, inconspicuous; leaves few, erect, pale, ovate-lanceolate, acute to acuminate; margins obscurely bordered, entire or irregularly serrulate, plane or recurved; costa often absent; cells longer than those in vegetative leaves, ± long-rhomboidal above, long-rectangular below; basal cells colored, sometimes with colored cells forming a pseudocosta. Setae elongate, roughened above, or rarely throughout, smooth below or rarely throughout, ± straight; capsules erect, ± ovoid; exothecial cells ± quadrate, collenchymatous; annulus none; operculum conicrostrate; columella almost as long as the urn, broadly cylindric; peristome double, attached at the mouth, pale or golden, exostome teeth triangular, not bordered or shouldered, recurved when dry, spiculose throughout, on front surface with a ± straight to zig-zag median line, not furrowed, scarcely trabeculate at back; endostome spiculose, with a low basal membrane, segments linear, ± keeled, not or narrowly perforate, ca. as long as the teeth, cilia none. Spores spherical, papillose. Calyptrae mitrate, usually just covering the operculum, ciliate at base, naked, usually ± roughened above.

• Discussion

  Discussion. Daltonia is recognized by its erect stems in tufts with singly costate, bordered leaves. The laminal cells are mostly oval and thick-walled. The capsules are erect with pale, spiculose peristomes. The calyptrae are mitrate and ciliate at base. Daltonia is distributed throughout the tropics, primarily at higher elevations in humid forests. Species representation is particularly high in the Andes and tropical Asia. In the West Indies there are only two, well-marked species. Both are treated in Bartram's (1931) admirable revision of the American species. The plants are small, often occurring on twigs in the canopy, and thus probably undercollected