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Australian ferns & fern allies |
 PlagiogyriaceaeErect terrestrial ferns of moderate size, rhizome short, stout, erect, radial, dictyostelic, neither scaly nor obviously hairy; the apex and young fronds covered by mucilage secreted by fine tangled hairs. Fronds stipitate, the stipe bases wide and flat with a deep abaxial ridge with a row of raised wart-like aerophores on each side, the remainder of the stipe with 2 rows of aerophores, the upper ones associated with vestigial pinnae, the stipe with a single shallow V-shaped vascular strand, the lamina pinnatifid or pinnate, the pinnae costate, adnate, sessile, or +/- stalked, the stalks and rachis +/- winged, the wings decurrent, aerophores often present at the base of each pinna, the pinnae glabrous, the veins free, simple or once-forked, close and parallel, terminating in a tooth or in the hyaline margin; fertile fronds on longer stipes, narrower, with much contracted pinnae +/- devoid of lamina. Sporangia covering almost the entire abaxial surface of the fertile pinnae, attached along the veins, exindusiate but +/- protected by the revolute margins, paraphyses usually present, annulus complete, oblique; spores trilete, tuberculate or almost smooth. DistributionA monogeneric family of c. 36 species, predominantly northern in distribution from Malesia, east Asia and America. In Papuasia the family is represented by 3 species. Genera
Plangiogyria is superficially similar to the quite unrelated genus Blechnum (Blechnaceae) and is often misidentified. Blechnum always has large scales at the base of the frond, Plagiogyria is always naked and often slimy. Australian National Herbarium page Updated November 1999 by Jim Croft (jrc@anbg.gov.au)  |
