All Floras      Advanced Search
Login | eFloras Home | Help
Chinese Plant Names | Family List | Athyriaceae

Diplazium Swartz

双盖蕨属

Description from Flora of China

Allantodia R. Brown; Anisogonium C. Presl; Callipteris Bory; Monomelangium Hayata.

Plants terrestrial, evergreen, medium-sized to large. Rhizome creeping to ascending or erect, sometimes subarborescent, brown or nearly black, dictyostelic, ± scaly; scales subulate, lanceolate, or broadly lanceolate, sometimes ovate and adpressed or peltate, margin entire, sometimes sparsely toothed and often narrow, black, brown, yellow-brown, or dark brown to black; fronds caespitose, distant or approximate. Stipe brown or black and scaly at base, scales similar to those on rhizome, and upward gradually glabrescent or with sparse scales, sometimes base and upward prickly, grooved adaxially, not hairy. Lamina mostly broadly ovate, oblong, or deltoid, sometimes broadly lanceolate, usually pinnate to tripinnate-pinnatifid under acuminate and pinnatifid apex, mostly bipinnate or bipinnate-pinnatilobate to bipinnate-pinnatipartite. Pinnae lanceolate, broadly lanceolate, or oblong-lanceolate, base mostly or nearly symmetrical, lower pinnae not reduced or slightly reduced; ultimate pinnules mostly lanceolate or broadly lanceolate, sometimes ovate or oblong, base stalked or sessile, truncate, rounded, or subcordate, margin entire or serrate, apex acute or acuminate to long acuminate, sometimes rounded or truncate; veins free, rarely anastomosing with a row of areoles along costa and costule; veinlets simple or forked, ascending, lower veinlets often curved. Lamina herbaceous or papery, rarely leathery, usually glabrous, rachis, costae, and costules abaxially sometimes with sparse subulate or lanceolate scales, rarely prickly; rachis, costae, and costules adaxially grooved between knife-edgelike ridges, ridges interrupted at insertion of higher-order frond axes, so grooves continuous, both surfaces of costa often with minute glandular hairs. Sori linear, oblong, or ovate, mostly single or less often double on basal acroscopic veinlets, costular, medial, supramedial, or from base to end of veinlets; indusia membranous or thickly membranous, grayish white or brown, vaulted or ovoid when mature, and irregularly rupturing on back, or compressed, linear, opening acroscopically, persistent or caducous. Spores bilateral, monolete, mostly reniform or bean-shaped, sometimes hemispherical, rarely spherical; perispore generally prominent, ornamentation mostly rugate, glabrous or aculeate, granular, clathrate, reticulate, rarely ridged. n = 41.

Most of the species in China are distributed south of the Chang Jiang and in SW regions on mountains; they occur in evergreen broad-leaved forests or beside shaded streamlets, and a few extend to 3000 m.

The following species, accepted in Knapp (Ferns Fern Allies Taiwan, 152, 451, 487. 2011), has been excluded from the present treatment: Diplazium proliferum (Lamarck) Thouars (Esquisse Fl. Tristan d’Acugna, 35. 1808; Asplenium proliferum Lamarck, Encycl. 2: 307. 1786; Callipteris prolifera (Lamarck) Bory). Further study is needed to establish its presence in Taiwan.

The following taxon, described from Guizhou, is excluded from the present treatment, pending further research: Diplazium platyphyllum Christ (Bull. Acad. Int. Géogr. Bot. 17: 148-149. 1907).

About 300-400 species: mainly distributed in the tropics and subtropics worldwide; a few species distributed in warm temperate and temperate zones or subalpine belts; 86 species (29 endemic) in China.

(Authors: He Zhaorong (和兆荣); Masahiro Kato)

  • List of lower taxa


     

  •  |  eFlora Home |  People Search  |  Help  |  ActKey  |  Hu Cards  |  Glossary  |