Monographs Details: Cyathea
Authority: Mickel, John T. & Beitel, Joseph M. 1988. Pteridophyte Flora of Oaxaca, Mexico. Mem. New York Bot. Gard. 46: 1-580.
Family:Cyatheaceae
Scientific Name:Cyathea
Description:Genus Description - Terrestrial; stem erect, usually a trunk, to 20 m tall, 10 cm diam. (without the occasional mantle of wiry adventitious roots), scaly at the apex; fronds large, to 4 m long; stipe stout, scaly, scales conform or marginate, often with sharp spines; blade bipinnate to bipinnate-pinnatifid, chartaceous to coriaceous; axes with long, sharp-pointed hairs on upper surface, often with bullate scales below; veins free, simple or forked; sori round, dorsal, with indusium arising from beneath the sorus and either completely enclosing it or forming a cup or a flat unequal-sided saucer, or lacking; sporangia with oblique annuli; spores tetrahedral-globose.

Discussion:Type: Cyathea arborea (Linnaeus) J. E. Smith [=Polypodium arboreum Linnaeus]. Alsophila R. Brown, Prodr. 158. 1810. Type: Alsophila australis R. Brown. (Additional synonymy in R. Tryon, 1970.) Hemitelia R. Brown, Prodr. 158. 1810. Type: Cyathea multiflora J. E. Smith. Sphaeropteris Bemhardi, J. Bot. (Schrader) 1800(2): 122. 1801. Type: Sphaeropteris medullaris (Forster) Bernhardi [=Polypodium medullare Forster]. (Additional synonymy in R. Try on, 1970.) Trichipteris Presl, Delic. Prag. 1: 172. 1822. Type: Trichipteris excelsa Presl [=T. corcovadensis (Raddi) Copeland]. (Additional synonymy in Barrington, 1978.) Sometimes treated under Trichopteris. For discussion of viewpoints of Trichipteris vs. Trichopteris, see Gastony (Amer. J. Bot. 66: 1258-1260. 1979) and Morton (Amer. Fern J. 61: 142-143. 1971). Nephelea R. Tryon, Contr. Gray Herb. 200: 37. 1970. Type: Nephelea polystichoides (Christ) R. Tryon [=Cyathea polystichoides Christ]. The squamate tree ferns have been treated either as a single genus (Holttum & Sen, 1962) or as six discrete genera (R. Tryon, 1970). We are treating them here in a broad sense since we see a recurrence of characters among the groups, such as the distinctive hairs and bullate scales, trunk habit, sorus and sporangial structure, etc. Furthermore, the extensive hybridization among the groups, including fertile diploids, makes their recognition as genera extremely tenuous. As construed here, Cyathea is distinguished by its distinct trunk over 1 m tall with indument of scales, 2-3-pinnate blade, free veins, and abaxial sori. References: Barrington, D. S. 1978. A revision of the genus Trichipteris. Contr. Gray Herb. 208: 1-93; Conant, D. S. 1983. A revision of the genus Alsophila (Cyathaceae) in the Americas. J. Arnold Arbor. 64: 333-382; Gastony, G. J. 1973. A revision of the fern genus Nephelea. Contr. Gray Herb. 203: 81-148; Gastony, G. J. 1979. Spore morphology in the Cyathea-ceae. III. The genus Trichipteris. Amer. J. Bot. 66: 1238—1260; Gastony, G. J. & R. M. Tryon. 1976. Spore morphology in the Cyatheaceae. II. The genera Lophosoria, Metaxya, Sphaeropteris, Alsophila and Nephelea. Amer. J. Bot. 63: 738-758; Holttum, R. E. & U. Sen. 1962. Morphology and classification of the tree ferns. Phytomorphology 11: 406-420; Maxon, W. R. 1909. Cyatheaceae. N. Amer. Fl. 16: 65-88; Maxon, W. R. 1922. Studies of tropical American ferns. No. 7. The North American species of Alsophila grouped with A. armata. Contr. U.S. Natl. Herb. 24: 33-46; Riba, R. 1967. Revisión monográfica del complejo Alsophila swartziana Martius (Cyatheaceae). Ann. Inst. Biol. Univ. México, Bot. 38: 61-100; Riba, R. 1969. The Alsophila swartziana complex (Cyatheaceae). Rhodora 71: 7-17; Riba, R. 1981. Cyatheaceae. Flora de Veracruz 17: 1-42; Tryon, R. M. 1970. The classification of the Cyatheaceae. Contr. Gray Herb. 200: 3-53; Tryon, R. M. 1971. The American tree ferns allied to Sphaeropteris horrida. Rhodora 73: 1-19; Tryon, R. M. 1976. A revision of the genus Cyathea. Contr. Gray Herb. 206: 19-98; Windisch, P. G. 1977. Synopsis of the genus Sphaeropteris (Cyatheaceae) with a revision of the neotropical exindusiate species. Bot. Jahrb. Syst. 98: 176-198.