Hypnaceae

Diagnosis: Plants small to medium-sized, in green to golden, extensive, loose mats. Stems stipitate, arched, wiry, radiculose at tips, freely and irregularly branched above sparsely foliate stipe. Stipe leaves differentiated, widely spaced, wide-spreading, ovate, 0.6-0.8 mm long, gradually short-acuminate, somewhat decurrent; margins serrulate almost to base; cells long-hexagonal to linear-oblong, smooth or sparsely prorulose at uppers ends at back, becoming rectangular toward the insertion; alar cells few, short-rectangular in extreme angles. Stem leaves erect- to wide-spreading, lanceolate to ovate-lanceolate, 0.45-1.3 mm long, gradually short-acuminate; margins serrate to serrulate above, serrulate to denticulate below; cells linear, sparsely prorulose at upper ends at back, only becoming shorter at extreme insertion; alar cells very few in 1-4 rows in extreme angles. Branch leaves laxly spaced, erect- to wide-spreading, lanceolate, 0.4-1.0 mm long, gradually short-acuminate, margins mostly serrate above, serrulate almost to base; cells long-hexagonal to linear-oblong, sparsely but usually conspicuously prorulose at upper ends at back, only becoming shorter at extreme insertion; alar cells quadrate to short-rectangular in 3-5 rows in extreme angles. Setae elongate, dark-red, 1-2 cm long; capsules inclined to pendent, arcuate, asymmetric, cylindric, 1.2-1.5 mm long, constricted below the mouth when dry; annulus of 1-2 rows of oval to rectangular thick-walled cells; exostome teeth shouldered, bordered, on the front surface cross-striolate below, coarsely papillose above, trabeculate at back. Spores 10-17 µm.

Distribution: Mexico; Central America; Caribbean, Western and Northern South America; Africa; India

Ecology: Found growing on a wide range of substrates from soil and rock to trees.

Notes: Mittenothamnium reptans is recognizable by its arched, sprawling stems. The plants are laxly foliate and the young leaves appear particularly serrate due to the serrations developing before full leaf size.

Basionym: Hypnum reptans Hedw.

Basionym Citation: Species Muscorum Frondosorum 265. pl. 68. 1801.

Other Published Figures: W. R. Buck. 1998. Pleurocarpous mosses of the West Indies. Plate 131 (11-19).