Erect, medium-sized terrestrial ferns. Rhizome creeping with spaced fronds, solenostelic, young parts protected by dark glossy bristles. Fronds long-stipitate, the stipes dark and polished proximally, adaxially grooved distally, the groove continous with the rachis and/or costae, 2 ribbon-like vascular bundles at the base, sometimes uniting distally to form one of "U"-shape, the lamina simple to pinnate (rarely with the lobes deeply divided), with the terminal lobe similar to the lateral lobes, the pinnae narrow-elliptic, entire, costate, coriaceous, glabrous, the veins forming a network of 2 or more series of narrow oblique areoles lacking free included veinlets; the fronds weakly or strongly dimorphic, the fertile fronds larger with strongly or slightly contracted pinnae. Sporangia spreading irregularly along the veinsor confined to a longitudinal band on a vascular commissure between the costa and the margin, formed by the longitudinal fusion of contracted sori on each vein, or immersed in a submarginal groove, or entirely covering the abaxial surface of contracted pinnae, exindusiate, paraphyses abundant protecting young sori, multicellular, the distal cells shortened and thickened, annulus longitudinal interrupted of c.15 thickened cells. Spores trilete.
Sect. Taenitis: fronds pinnate; the fertile pinnae not strongly contracted; soir spreading along the veins or +/- contracted into a sometimes interrupted longitudinal intramarginal band.
Sect. Platytaenia: fronds pinnate; the fertile pinnae strongly contracted; the sori completely covering the lower surface of the pinnae.
Sect. Schizoloma: fronds simple of trifid; the fertile pinnae not strongly contracted; the sori immersed in a marginal groove, +/- protected by the reflexed inner and outer edges of the groove.
Species in Papuasia
|1a.||Sori superficial on the lower surface of the lamina...||2|
|Sori in apparently marginal or almost marginal grooves...||T. cordata|
|2a.||Sporangia not entirely covering the lower surface of the fertile pinnae...||3|
|Sporangia quite covering the lower surface of very narrow fertile pinnae...||5|
|3a.||Fronds of mature plants pinnate; sporangia spreading along the veins, or in a continuous band parallel to the midrib...||4|
|Fronds of mature plants simple; sporangia spreading along almost all veins of the lower surface...||T. hookeri|
|4a.||Sporangia in a continuous band parallel to the midrib...||T. blechnoides|
|Sporangia +/- spreading along individual veins...||T. pinnata var. pinnata|
|5a.||Sterile pinnae to 20 x 3.7cm, widest at the middle, narrowly acuminate; fertile pinnae up to 19 cm long; terminal cell of paraphyses not different from the next...||T. requiniana|
|Sterile pinnae to 12 x 3cm, widest below the middle, short acuminate; fertile pinnae 10-15 cm long; terminal cell of paraphyses larger than the next, club-shaped, curved, thick-walled...||T. diversifolia|