Stenochlaena J. Sm.
Moderate to large, high-climbing ferns with scandent rhizomes, often in swamps or beside rivers. Rhizome naked, green, apically bearing many rotund or elongate, peltate scales, radially symmetric, vascular system a complex dictyostele of several large central bundles surrounded by 2 irregular rings of many smaller bundles. Fronds widely spaced, stiped glabrous, +/- ducurrent with the rhizome, with corresponding vasculature, the lamina pinnate with alternate pinnae and a terminal pinnae similar to the laternal pinnae, dimorphic, the fertile lamina much contracted (in one species bipinnate); the sterile lateral pinnae usually articulate, with a basal acroscopic gland, costate with fine, close, free veins arising from a series of narrow, elongate, costal aeroles, coriaceous, glabrous, margin cartilaginous and sharply tootched; fertile pinnae narrow, linear, entire. Sporangia borne in an elogate coenosorus occupying the area from the costal areoles almost to the margin of the fertile pinnae, supplied by a secondary vascular system, exindusiate, paraphyses lacking, annulus longitudian, interrupted, of 12 - 20 thickened cells. Spores monolete, translucent, tuberculate or with continuous or broken ribs.
Species in Papuasia
|1a.||Pinnae commonly 15 pairs or more, the sterile pinnae to at least 15 x 3 cm, the fertile pinnae with a very narrow sterile margin; not restriced to Pandanaceae...||2|
|Pinnae to 7 pairs, sterile pinnae to 10 x 2.2 cm, fertile pinnae c. 3 mm wide with thin reflexed sterile margins 1 mm wide; restricted to crowns on Pandanaceae...||S. areolaris|
|2a.||Lower pinnae at least appearing fully artuculate when dry, bases of sterile pinnae cuneate; fertile pinnae 2 - 3 mm wide; spores evenly tuberculate throughout...||S. palustris|
|Pinnae not distinctly articulate, bases of steril pinnae broadly rounded; fertile pinnae c. 5 mm wide; spores with irregularly broken ridges...||S. milnei|