Jeweled maiden fern

Description

Thelypteris extensa is Rhizome erect, with tufted fronds and with dark-brown attenuate, minutely ciliate rhizome-scales up to 9 mm. long. Frond arching, non-proliferous, membranous. Stipe up to 40 cm. long, brown nitid, darker at the base, sparsely and minutely pubescent with short white hairs and with dark-brown scales similar to those on the rhizome, towards the base. Lamina up to 1 x 0.60 m., deeply 2-pinnatifid, broadly oblong-acute in outline with the basal pinnae not reduced. Pinnae up to 35 x 2.9 cm., very narrowly oblong in outline in upper pinnae, lanceolate in lower pinnae, attenuate-caudate, the basal pinnae narrowed towards the base, pinnatifid into somewhat falcate narrowly oblong acute entire lobes, up to 1.2 x 0.5 cm., glabrous on both surfaces except for curved white hairs on the ventral costa and margin, and sparsely pubescent on the costa dorsally and with yellow glands along the veins; 1 pair of veins anastomosing. Sori up to 16 per lobe; indusium up to 0.6 mm. in diam., with yellow glands.