in P. Bruch and W. P. Schimper, Bryol. Europ. 5: 157, plates 481 – 486. 1852
North America, Mexico, West Indies, Central America, South America, Europe, Asia.
Species ca. 230 (4 in the flora).
Thuidium is characterized by abundant, 2- or 3-pinnate paraphyllia; dioicous sexuality; dimorphic stem and branch leaves with short, thick-walled cells that are papillose abaxially and nearly always 1-papillose; stem leaves with base ± plicate and laminal cells ± uniform; apical cells of branch leaves usually truncate and multipapillose; and setae nearly always smooth. The capsule is smooth, with a short neck. The genus is treated here in a sense exclusive of Abietinella, Cyrto-hypnum, and Rauiella (see W. R. Buck and H. A. Crum 1990). Abietinella is relatively robust and has 1-pinnate branching, abundant paraphyllia, dioicous inflorescences, laminal cells 1-papillose on both surfaces, and 3- or 4-celled, brown axillary hairs. Cyrto-hypnum and Rauiella are small with autoicous inflorescences, paraphyllia short and not much branched, and laminal cells papillose on both surfaces (most commonly multipapillose). Cyrto-hypnum has mostly 2-pinnate branching, 2-celled axillary hairs, leaves incurved when dry, laminal cells plane, and setae often roughened. Rauiella has 1-pinnate branching, 3-celled axillary hairs, leaves not incurved when dry, strongly bulging laminal cells, and smooth setae.
|1||Stems usually 3-pinnate; branch leaf apical cell acute, smooth.||Thuidium tamariscinum|
|1||Stems usually 2-pinnate; branch leaf apical cell truncate, multipapillose||> 2|
|2||Stem leaves incurved basally and spreading apically when dry, distinctly plicate; costae nearly filling acumen; paraphyllia papillose at cell ends.||Thuidium recognitum|
|2||Stem leaves ± erect when dry, not or somewhat plicate; costae not filling acumen; paraphyllia papillose at sides of cells or cell ends||> 3|
|3||Stem leaf apices short-pointed; margins plane or sometimes reflexed basally; distal laminal cells appearing 1-3-papillose because papillae 2-fid.||Thuidium alleniorum|
|3||Stem leaf apices acuminate; margins revolute throughout; laminal cells coarsely 1-papillose, not appearing multipapillose, papillae sometimes 2-fid.||Thuidium delicatulum|
|Author||Howard A. Crum† +|
|Authority||Schimper in P. Bruch and W. P. Schimper +|
|Distribution||North America +, Mexico +, West Indies +, Central America +, South America +, Europe + and Asia. +|
|Etymology||Genus Thuja and Latin -idium, diminutive, alluding to branched habit +|
|Illustration copyright||Flora of North America Association +|
|Illustrator||Patricia M. Eckel +|
|Publication title||in P. Bruch and W. P. Schimper, Bryol. Europ. +|
|Publication year||1852 +|
|Source xml||https://firstname.lastname@example.org/aafc-mbb/fna-data-curation.git/src/f50eec43f223ca0e34566be0b046453a0960e173/coarse grained fna xml/V28/V28 597.xml +|
|Taxon family||Thuidiaceae +|
|Taxon name||Thuidium +|
|Taxon parent||Thuidiaceae +|
|Taxon rank||genus +|
|Volume||Volume 28 +|