Monographs Details: Ctenitis
Authority: Mickel, John T. & Beitel, Joseph M. 1988. Pteridophyte Flora of Oaxaca, Mexico. Mem. New York Bot. Gard. 46: 1-580.
Description:Genus Description - Terrestrial; rhizome erect to sometimes horizontal, scaly; fronds medium-sized to large; blade pinnate-pinnatifid to quadripinnate, catadromous, herbaceous to chartaceous; axes, especially the adaxial surface, with short, reddish-brown, articulate hairs (ctenitoid hairs) or with pale sharp-pointed hairs (resembling those of tree ferns), abaxially with few to many scales, often bullate, sometimes clathrate or plane and with some hairs; veins free; sori abaxial, roundish, indusia reniform, attached at sinus, sometimes much reduced or even lacking altogether; spores bilateral, echinulate.
Discussion:Type: Ctenitis distans (Brack-enridge) Ching [=Aspidium ctenitis Link].
Ctenitis is a genus of about 150 species, about evenly distributed between the Old and New World wet tropics, mostly of low and middle elevation. It is probably related to the tectarioid ferns, being most closely allied to Lastreopsis.
The C. subincisa group lacks the typical ctenitoid hairs but rather has on its adaxial rachises antrorse, stiff, acicular hairs typical of the cyatheoid tree ferns. Furthermore, it has toothed rhizome and stipe scales resembling those in Cy-athea subg. Sphaeropteris, and although the spores are bilateral, their surface architecture appears similar to that in other species of Cyathea. There is no suggestion that there is a close relationship between Ctenitis and Cyathea, but this is an interesting case of parallelism, and the C. subincisa group could be treated as a distinct genus.
References: Christensen, C. 1913-1920. A monograph of the genus Dryopteris. Part 1. The tropical American pinnatifid-bipinnatifid species. Kongel. Danske Vidensk. Selsk. Skr., Naturvidensk. Afd. VII, 10: 55-282. 1913. Part II. The tropical American bipinnate-decompound species. Op. cit. VIII, 6: 1-132. 1920.