Cyrto-hypnum mexicanum (Mitt.) W.R.Buck & H.A.Crum
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Authority
Sharp, Aaron J., et al. 1994. The Moss Flora of Mexico. Part Two: Orthotrichales to Polytrichales. Mem. New York Bot. Gard. 69 (2)
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Family
Thuidiaceae
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Scientific Name
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Description
Species Description - Slender, light-green or yellowish plants. Stems creeping, irregularly pinnate or bipinnate; paraphyllia numerous on stems, 2-5 cells long, very short or linear, ending in a conic cell bearing 1-2 very small papillae. Stem leaves strongly incurved when dry, wide-spreading when moist, broadly ovate, acuminate, obscurely plicate near the base, 0.6-0.7 mm long; margins sometimes narrowly recurved near the basc; costa yellowish, ending near the apex; cells thin-walled, obscure, 4-6 µm, unipapillose on both surfaces. Branch leaves incurved-catenulate when dry, wide-spreading with ± incurved points when moist, ovate, obtuse or broadly acute, concave-keeled, about 0.15-0.3 long; costa extending about 8/10 the leaf length; cells bulging and unipapillose on both surfaces. Autoicous. Perichaetial leaves up to 1.5 mm long, lanceolate, slenderly acuminate, not ciliate. Setae 9-18 mm long, smooth, red; capsules 1.5-2.5 mm long, erect or rarely smewhat curved, cylindric; operculum long-rostrate; annulus of 2 rows of cells; endostome lightly papillose, cilia none, rudimentary, or sometimes well developed (and single or paired). Spores 12-16 µm, minutely roughened.
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Discussion
Fig 656
C. mexicanum (Mitt.) Buck & Crum, Contr. Univ. Michigan Herb. 17: 66. 1990.
Thuidium mexicanum Mitt., J. Linn. Soc, Bot. 12: 577. 1869.
? Hypnum siphotheca C. Mull., Bot. Zeitung 16: 171. 1858.
Thuidium orthocarpum Besch., Mem. Soc. Sci. Nat. Cherbourg 16: 234. 1872.
?T. siphotheca (C. Miill.) Jaeg., Ber. Thatigk. St. Gallischen Naturwiss. Ges. 1876-77:255. 1878.
T. pellucens Ren. & Card., Bull. Soc. Roy. Bot. Belgique 32(1): 198. 1894.
T. costaricense Broth. & Ther. ex Ther., Rec Publ. Soc. Havraise Etudes Div. 88: 314. 1921.
Cyrto-hypnum mexicanum is very distinctive in having unipapillose leaf cells and paraphyllia mostly ending in a conic cell. The capsule is typically erect and narrowly cylindric, although it is occasionally somewhat asymmetric and inclined. Also in Guatemala and Mexico is another species with unipapillose leaf cells, C. sharpii, but it has curved and inclined capsules on setae that are rough above, and the paraphylha end in a short, tmncate, pluripapillose ceU. Cyrtohypnum leptocladum (Tayl.) Buck & Crum , of South America, has unipapillose leaf cells but smooth setae, inchned capsules, and paraphyllia ending in a tmncate, pluripapillose cell.
A fragmentary specimen of Hypnum siphotheca C. Müll. (MICH) unquestionably belongs here. It was labeled by Mrs. Britton as "Hypnum siphotheca C. Müll. Guatemala," but on the reverse side of the paper she wrote Guatemala and Venezuela. Unfortunately there is no way to identify this material as Guatemalan; the name is, of course, older than Mitten's Thuidium mexicanum.
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Distribution
On bark at base of trees, logs, stumps, and rock in moist places at 1700-3100 m alt.; Chiapas, Distrito Federal, Guerrero, Hidalgo, Jalisco, Mexico, Michoacan, Morelos, Nayarit, Oaxaca, Puebla, Veracruz.—Mexico; Guatemala and Costa Rica.
Costa Rica South America| Guatemala Central America| Mexico North America|