Rhizome 2 mm thick (dorsoventrally flattened), internodes to 1.5-2 cm long; vascular strands with bundle sheath hyaline or partially sclerified; sclerenchyma strands many, sclerified sheath present. Rhizome scales peltate, appressed to spreading, 4-5.5 by 1 mm, acute, straw-coloured or brown with a lighter margin, sometimes with irregular dark spots, remotely and weakly dentate. Fronds simple, strongly dimorphic. Fertile fronds with stipe 8-14 cm long; lamina 3.5-10 by 0.3-0.6 cm, index 9-12, widest at 0.4-0.5 from base or linear. Sterile fronds with stipe 0.8-6.5 cm long; lamina 2.5-5 by 0.9-2.7 cm, index 1.4-3.7, widest at 0.2-0.5 from base. Venation: main veins on upper surface raised, distinct; veinlets anastomosing, free veinlets excurrent and recurrent. Hydathodes frequent, relatively large and conspicuous, calcareous scales not persistent. Margin cartilaginous, thickened; notches regularly present. Sori round, in two rows between adjacent veins, often confluent to a longitudinally elongated sorus, in one row between costa and margin (occasionally a few sori in a second row), 1.5-2 mm wide, superficial.
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