Erect epiphytic or subepiphytic, less often rupestral, ferns of small or moderate size. Rhizome usually short-creeping with stipes close together in a mass of fibrous roots, bearing broad, ovate to lanceolate, peltate-based, entire or toothed, clathrate scales, dictyostelic, each vascular bundle surrounded by a sheath of sclerenchyma, often with additional strands of schlerenchyma in the medulla and cortex. Fronds mostly +/- erect, the lamina decurrent into a short stipe, articulate to short phyllopodia, a single leaf-trace entering the stipe and dividing rapidly into 3 or more fibro-vascular bundles arranged in a U- or V-shape, the two adaxial bundles usually larger, the lamina simple, entire, elongate-elliptic to almost linear, leathery, coriaceous, glabrescent, costate, veins immersed and obscure, oblique main lateral veins present but poorly developed, secondary veins reticulate, the areoles with included, free, simple or branched, variously directed veinlets, each ending in a hydathode visible on the adaxial surface of the lamina; fertile fronds abruptly constricted apically and soriferous. Sporangia in an elongate, linear, intramarginal coenosorus either side of the apical costa, completely covering the abaxial surface except for a marginal band on the +/- linear apex of fertile fronds, served by a complex costal secondary vascular network, exindusiate, but protected by peltate, clathrate, toothed scales and various other paraphyses, and the revolute margins of fertile segments, annulus longitudinal, interrupted, of c.14 thickened cells, pedicel long, 3-seriate. Spores monolete, smooth, translucent.
Species in Papuasia
|1a.||Apex abruptly constricted, completely covered by sporangia; lamina stiff and leathery, secondary veins immersed and invisible; rhizome long-creeping||
|Apex gradually attenuate, some sterile lamina between costa and sorus; lamina +/- herbaceous, secondary veins visible; rhizome long-creeping||
gen.nov. (Lemmaphyllum novoguineensis)
|2a.||Fronds 60 cm long or longer, 4-5 cm wide, arching and +/- pendlous, fertile apices pendulous, apparently restricted to Pandanus||
|Fronds mostly less than 30 cm long, less than 4 cm wide, held erect, fertile apices erect, not restricted to Pandanus||
|3a.||Fronds with revolute margins, generally c.1-1.5 cm wide||
|Fronds with flat or recurved margins, generally c.2-4 cm wide||
Gen. Nov. (Lemmaphyllum novoguineensis)
Climbing epiphyte or subepiphyte of small size. Rhizome long-creeping with spaced fronds and scattered fibrous roots, bearing lanceolate, peltate-based, entire, clathrate scales, dictyostelic, each vascular bundle surrounded by a sheath of sclerenchyma, with additional strands of schlerenchyma in the medulla and cortex. Fronds +/- erect, stipitate, the stipe winged apically, articulate to short phyllopodia, with 3 fibro-vascular bundles arranged in a V-shape, the two adaxial bundles larger, the single abaxial bundle vanishing as the stipe enters the lamina, the lamina simple, elongate-lanceolate, entire, herbaceous to subcoriaceous, glabrescent, costate, main lateral veins distinct, oblique, cross-veins forming a series of long areoles near the costa each with a single included, free, recurrent vein with 2 long branches ending in hydathodes, additional series of areoles less regular, with free, included, simple or branched, mostly recurrent veins ending in hydathodes; fertile fronds gradually attenuate apically and soriferous, some sterile lamina between the costa and sorus. Sporangia in submarginal, elongate, linear coenosori either side of the costa, the receptacle supplied by a secondary vascular network running +/- along the outer margin of the first series of areoles, exindusiate, but protected by peltate, clathrate toothed scales and various other paraphyses and the revolute margins of the fertile segments, at least on young fronds, annulus longitudinal, interrupted, of c.14 thickened cells, pedicel long, 3-seriate. Spores monolete, smooth, translucent.
Species in Papuasia