Terrestrial ferns of medium to large size. Rhizome short- to long-creeping, solenostelic with a sclerotic medually strand, or if slender then protostelic with a solid fobrovascular bundle with internal phloem, (Lindsaeoid protostele), bearing basally attached, concolourous, elongate to acicular scales, the scales sometimes uniseriate apically and appearing as hairs. Fronds long-stipitate, the stipe with a single V- or U-shaped vascular bundle, abaxially terete, adaxially grooved upwards, the grooves and edges continuous with those of the higher order branches, the lamina pinnately decompound, broadly deltoid in outline, the apical pinnae gradually reduced, strongly anadromous, the terminal segments +/- obdeltoid, lacking a costule, the veins free, simple or several-times forked, terminating short of the margin. Sori +/- apical, terminal on a single vein or uniting 2-3 or more veins, the indusium attached basally and +/- at the sides, opening towards the apical margin, paraphyses 2-3 celled, fugacious; sporangia with a triseriate stalk; the annulus longitudinal, interrupted, of 14-18 thickened cells. Spores monolete or trilete, smooth.
Species in Papuasia
|1a.||Rhizome 2-4 mm diam., protostelic with a central strand of phloem (Lindsaeoid protostele0; scales to 4 mm long, to 4-seriate at the base; spores monolete; sori on larger segments on 1-2(-4) vein ends, not occupying the whole apical margin (S. chinensis)||2|
|Rhizome 5-20 mm diam., solenostelic with an internal sclerotic strand; rhizome scales sometimes to 7 mm long and 20-seriate at the base; spores trilete; sori on the larger segments on (2 - ) 4-8 vein ends, occupying their whole apical margin||3|
|2a.||Sori mostly with 2-3 veins||S. chinensis var. chinensis|
|Sori mostly with a single veing||S. chinensis var. divaricata|
|3a.||Divisions of the highest order of lanceolate outline (the penultimate ones) almost entirely dissected into cuneate segments, sometimes twice dissected, their apices caudate acuminate; rhizome scales to 7 mm long, to 20 seriate at the base||S. retusa|
|Divisions of the highes order of lanceolate outline (penultimate or ultimate ones) only at the base with a few broadly cuneate, free or almost free segments and a shallowly incised apical portion, the apices of these divisions acute or shortly acuminate; rhizome scales to 4 mm long, 4-seriate at the base.||S. deltoidea|