Erect terrestrial ferns of moderate size. Rhizome creeping, solenostelic, or more often compact and dictyostelic, densely clothes in entire, basally attached, +/- clathrate scales. Fronds long stipitate, the stipe and rachis adaxially grooved, with a single "U"-shaped vascular strand, the lamina bipinnate-pinnatifid to 4-pinnate-pinnatifid, deltoid, glabrous, herbaceous to subcoriaceous, all axes grooved with the grooves open to admit those of higher orders; veins simple or forked, free except in the sori; fronds +/- uniform to dimorphic, the fertile fronds of portions with less finely divided segments, the pinnules broader and entire. Spornagia in a continuous submarginal coenosorus on a vascular commisure connecting the vein endings, protected by a broad, reflexed, entire, scariose, marginal or submarginal indusium (or pseudoindusium), the fertile pinnules narrowed so that the indusia meet over the costa, paraphyses absent; annulus longitudinal, interrupted, of c.20 thickened cells, with a distinct wide stomium. Spores trilete, hyaline and with a thick, ribbed or tuberculate perispore.
Species in Papuasia
|A single species in Papuasia...||O. siliculosum|