Plants small to large, ± glaucous, green to rusty brown. Stems with branches erect to arcuate, sometimes attenuate to flagellate distally; central strand cells differentiated or not; pseudoparaphyllia absent in all but 2 species. Branch leaves appressed to moderately secund or crispate when dry, complanate or erect to imbricate when moist, broadly ovate to lanceolate, ± abruptly narrowed mid leaf, not plicate proximally (somewhat plicate in A. longifolius); margins plane, sometimes undulate or revolute, entire, papillose, crenulate, serrulate, or sometimes denticulate near apex; apex rounded, obtuse, acute, or narrowly acuminate; costa usually strong, sometimes obscured by laminal cells and ending before mid leaf, sometimes discreetly, asymmetrically 2-fid at end, abaxial costa cells smooth or papillose; laminal cells hexagonal, obscure to irregular, small, papillae 1 or many, high, on both surfaces, walls thin; basal cells sometimes oblong, pellucid, smooth, walls incrassate. Perichaetial leaves well differentiated. Seta to 2.2 cm. Capsule symmetric; stomata sometimes present; peristome reduced (well developed in A. rostratus); exostome teeth white to pale brown, densely papillose, occasionally cross striolate, sometimes slightly trabeculate; endostome sometimes very reduced or absent (sect. Haplohymenium), basal membrane 2–7 cells high, segments keeled to linear and reduced or absent. Calyptra smooth to papillose or hirsute (sect. Haplohymenium). Spores 9–20(–23) µm.
North America, Mexico, West Indies, Central America, South America (Bolivia), Europe, s Africa, Pacific Islands (New Zealand), Australia, temperate, circumboreal regions.
Species 16 (8 in the flora).
Anomodon viticulosus grows mostly on shaded calcareous outcrops, but the other species are found on tree trunks, including their base, logs, or sometimes soil or rock. Anomodon attenuatus, A. minor, and A. rostratus may grow on the same tree, with A. rugelii sometimes joining them in submontane regions. Although A. tristis may be found growing with the above species, it usually forms much thinner, more delicate mats higher on the tree. In North America, at least two species (A. attenuatus and A. rostratus) fruit profusely; A. minor and A. rugelii fruit less abundantly and perhaps less frequently, while sporophytes of A. viticulosus are extremely rare in North America (only one fertile specimen of A. viticulosus seen, none of A. tristis).
Haplohymenium was created to accommodate plants that resemble Anomodon but are more slender and have a papillose calyptra with long, hyaline scattered hairs. Segregating Haplohymenium would make the rest of Anomodon paraphyletic, as Haplohymenium is a sister group of A. minor, A. rugelii, and A. viticulosus, all of which are part of subg. Anomodon (Í. Granzow-de la Cerda 1997); these taxa are more distantly related to subg. Pseudoanomodon (Limpricht) Ochyra, to which A. attenuatus and A. rostratus belong.
|1||Branch leaves long-lanceolate; apices ending in hair-point or subulalike||> 2|
|1||Branch leaves ligulate; apices rounded, obtuse, acute, or apiculate, not ending in hair-point or subulalike||> 3|
|2||Stems profusely branched; primary branches erect.||Anomodon rostratus|
|2||Stems sparingly branched; primary branches prostrate or pendulous.||Anomodon longifolius|
|3||Plants small; stems less than 1 mm thick when dry; branch leaves less than 2.1 mm; apices often broken off; costa ending much before apex, obscured by laminal cells distally||> 4|
|3||Plants small to large; stems usually more than 0.8 mm thick when dry; branch leaves sometimes greater than 2 mm; apices intact; costa ending near apex, not or rarely obscured by laminal cells distally||> 5|
|4||Stems 0.3-0.5 mm thick when dry; leaves 0.5-0.9 mm; basal laminal cells few, region not reaching margin; costa weak, obscured by laminal cells almost throughout.||Anomodon tristis|
|4||Stems 0.5-1 mm thick when dry; leaves 1.2-1.8(-2.1) mm; basal laminal cells many, region reaching margin; costa moderately strong, obscured by laminal cells distally.||Anomodon thraustus|
|5||Plants dark green to rusty brown; leaves incurved-contorted when dry; bases auriculate; costae golden yellow to rusty brown; pseudoparaphyllia present.||Anomodon rugelii|
|5||Plants green to yellowish; leaves erect, imbricate, appressed or rarely slightly crisped when dry; bases broadly decurrent; costae pellucid or light green; pseudoparaphyllia absent||> 6|
|6||Plants large; stems 1-1.8 mm thick when dry; leaves flexuose, secund, spreading when moist, erect when dry, greater than 2 mm.||Anomodon viticulosus|
|6||Plants medium-sized to large; stems usually less than 1 mm thick when dry; leaves complanate when moist, appressed when dry, usually less than 2 mm||> 7|
|7||Stems not pinnate, secondary branches not attenuate, often slightly clavate at apices; perichaetia on terminal branches, beyond distalmost branching points; leaves abruptly narrowed mid leaf; apices rounded; margins entire at apex; abaxial costa cells with rounded-simple papillae in rows.||Anomodon minor|
|7||Stems irregularly pinnate, secondary branches attenuate at apices; perichaetia never present beyond distalmost branching points; leaves slightly narrowed mid leaf; apices acute, sometimes obtuse or slightly apiculate; margins sometimes denticulate at apex; abaxial costa cells smooth.||Anomodon attenuatus|