Daltonia Hook. & Taylor

Plants small to medium-sized, lustrous, yellow-green to golden, caespitose, epiphytic. Stems erect, simple or branched, several usually arising from a common point. Leaves spirally inserted, not in distinct ranks, closely-spaced, symmetric, ± erect and straight when moist, linear-lanceolate to ovate-lanceolate, acuminate to finely hair-pointed, recurved or plane, bordered; upper laminal cells smooth, firm-walled, linear-rhombic, oval to ± hexagonal, becoming longer, thinner-walled, and oblong or linear-rhombic towards base; border of few to several rows of thick-walled and linear cells; alar cells not differentiated. Costa single, narrow, unforked, ending well below the leaf apex. Propagulae sometimes clustered in leaf axils, uniseriate, fusiform. Axillary hairs 2–3-celled, the basal cell short and brown, the distal cell/s longer and hyaline.

Autoicous or synoicous. Perichaetia scattered on stems, inconspicuous, the inner leaves ovate to ovate-lanceolate, acute to acuminate, scarcely bordered, weakly costate. Perigonia mostly scattered on bisexual stems. Setae lateral, ± straight, scabrous above or less often hirsute or smooth throughout; capsules erect, symmetric, oblong-cylindric to ovoid; exothecial cells isodiametric and collenchymatous; annulus absent; operculum conic-rostrate. Peristome double, pale, inserted at the mouth; exostome teeth linear-lanceolate, neither bordered nor shouldered, not furrowed, with a ± straight median line, finely baculate-spiculose throughout, lacking marginal trabeculae, on the inner surface with low lamellae and baculae; endostome lacking a basal membrane, segments ± equal the teeth in length, lacking perforations, baculate throughout; cilia absent. Calyptra mitrate, lacking hairs, strongly fimbriate at base. Spores small.

Daltonia is a genus of 30 or more species which is widespread in tropical and subtropical areas, particularly in moist, high elevation forests. Representatives often grow on twigs. Only one species is recognised in the N.Z. flora, but there are difficulties in interpreting the relationship of Crosbya nervosa to this genus (discussed under Crosbya).

Buck (1998) characterised the genus 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."

Streimann (2000) treated two species of Daltonia from Australia and differentiated them largely on the degree of leaf contortion in dry plants.