Lastrea Bory.

Plants small to medium-sized, of marshes and meadows. Rhizomes long creeping, black, glabrous, sparsely covered with scales at apices; scales ovate-lanceolate, with acicular hairs and unicellular glandular hairs on surfaces and along margins. Fronds remote or approximate, stipitate; stipes nearly black at bases and slightly acicular hairy, distally stramineous, glabrous; laminae oblong-lanceolate, not tapering or slightly tapering to bases, pinnate-pinnatifid, shortly acuminate at apices; pinnae mostly nearly flat-spreading, lanceolate, bases truncate, symmetrical, pinnatifid, apices acute or shortly acuminate; segments ovate-triangular or oblong, shortly pointed at apices; veins free, pinnate on segments, veinlets forked or simple, reaching margins. Laminae thickly herbaceous or somewhat leathery, both surfaces with few acicular hairs when young, glabrescent when old, costae each with a groove adaxially, abaxially raised, sometimes with few membranous small scales. Sori orbicular, dorsifixed on veinlets, located between costules and margins, in one line on each side of costules, usually ± covered by reflexed margins; indusia membranous, orbicular-reniform, greenish, deciduous or hidden in mature sori; sporangia each with 1 or 2 short capitate glandular hairs close to tops of annuli; spores bilateral, reniform, perispores transparent, echinate, exospore smooth. x = 35.

In the past, Thelypteris has been defined to contain most or all species in the family. More recent studies show that, using multiple additional characters, like types of hairs, glands, venation, lamina shape and dissection, indusial characters, aerophores, adaxial grooves, spores, and chromosome base numbers, natural groups can be utilized to define smaller subsets of Thelypteris s.l. Here, we adopt a narrow concept for classification.

Four species: temperate regions of N Hemisphere, S tropical and S Africa, India, Madagascar, New Guinea, New Zealand; two species in China.

(Authors: Lin Youxing (林尤兴); Kunio Iwatsuki)