Pteridophyte genera

Tapeinidium (Presl) C.Chr.

Terrestrial ferns of small to medium size. Rhizome short- to moderately long-creeping, solenostelic with a sclerotic medullary strand, or if slender then protostelic with a solid fibrovascular 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 edgescontinuous with those of the higher order branches, the lamina leathery, pinnately to tripinnately compound, oblong-lanceolate to deltoid in outline, the apical pinnae gradually reduced, or +/- the same as the lateral pinnae, strongly anadromous, ultimate free segments with a costa or costule, the veins free, simple or forked, terminating short of the margin. Sori +/- submarginal, terminal on a single vein or uniting 2 veins, the indusium attached basally and +/- at the sides, opening towards the apical margin, paraphyses several-celled; sporangia with a triseriate stalk, the annulus longitudinal, interrupted, of c.15 thickened cells. Spores monolete, smooth.

Species in Papuasia

1a.	Lamina simply pinnate with a conform terminal pinna	2
	Lamina more strongly dissected	3
2a.	Petiole and rachis dark, abaxially +/- sharply biangular, pale-margined, often sulcate; sori close to the margin, mostly binerval, on the acroscopic margin of a serration; margins with a single level of serration.	T. longipinnulum
	Petiole and rachis purplish-brown, terete or abaxially obtuse-biangular, not pale-margined, not sulcate; sori remote from the margin, mostly uninerval, within a crenation; margins with 2 levals of crenation.	T. melanesicum
3a.	Primary rachis abaxially sharply carinate; at least a considerable upper portion of the stipe abaxially binangular	T. denhamii
	Primary rachis abaxially terete or biangular, or if obtusely carinate then the stipe not (or only at the apex) sharply biangular	4
4a.	Primary rachis dark, at least at the base; secondary rachises pale; pinnae pinnate-pinnataifid or subbipinnate; sori longest in the direction of the vein	T. stenocarpum
	Primary rachis pale, or if dark then the secondary rachises not abruptly pale; lamina often more incised	5
5a.	All axes, except the primary, green-margined to the base, or almost so (ie. The lamina only once fully pinnate, then pinnatifid; secondary axes abaxially rounded.	T. buniifolium
	Lamina mostly fully bipinnate; secondary rachises, if green-margined, abaxially carinate	6
6a.	Secondary rachises abaxially black, with 2 pale lateral or 1 pale median ridge; lamina bipinnate or almost so, with superficially crenate-lobed pinnules	T. atratum
	Secondary rachises abaxially various, but not black with pale ridges; lamina often bipinnate-pinnatifid	7
7a.	Primary rachis and indusia black; ultimate lobes with very broad and prominent veins occupying 1/3-3/4 of their width	T. obtusatlum
	Primary rachis and indusia pale to dark brown; ultimate lobes with immersed, or if slightly prominent then relatively much narrower veins	8
8a.	Indusia c. twice as long in the direction of the vein as across it, c.1/3 mm across; the margin bordening the apical sorus of the segment usually denticulate; texture herbaceous	T. denhamii
	Indusium wider across the direction of the vein, or if only c.1/3 mm across then +/- isodiametric; the margin bordering the apical sorus entire, or no apical sorus; texture firmer	9
9a.	Larger segments pinnatifid, each lobe with a sorus overtopped by part of the lobe	T. amboinense
	Larger segmetns (except for basal pinnaee) crenate, each lobe with a terminal or subterminal sorus	T. novoguineense