Plants aquatic, mat-forming. Rhizome filiform, creeping, irregularly branched, up to 0.24 mm diam., set with 1-5 roots at nodes, internodes (1.47-)2.70(-4.2) mm long, initially sparsely hairy, glabrous with age, mostly with a few hairs at frond base, hairs up to 5 cells long. Fronds borne singly at nodes, erect, simple, setiform, (8.9-)11.98(-13.66) mm long, basally with few laterally attached, 3-celled hairs, glabrous apically. Sporocarp subterranean, globose, (1.49-)1.58(-1.7) mm diam., laterally attached, cream-coloured and densely hairy when young, atrocastaneous and sparsely hairy when mature, hairs up to 5 cells long, appressed; sporocarps 4-locular, dehiscing into 4 valves, each locule with a single sorus containing micro-and megasporangia; sporocarp pedicel arising from node on rhizome, up to 1.43 x 0.21 mm, produced laterally. Microsporangia clavate, several per sorus, wall one cell layer thick, hyaline, each bearing 28-32 microspores. Microspores trilete, circular in polar view, elliptic in equatorial view, laesurae short, perispore hyaline, much larger than spore, epispore densely rugulate, (44.23-)49.88(-53.41) µm diam. at equator and (36.03-)42.25(-51.95) µm diam. at poles, pseudo-endospore (intine) evident below exine layer. Megasporangia ellipsoid, wall one cell layer thick, hyaline, 3-5 per sorus (12-19 per sporangium), each bearing a single megaspore. Megaspores spherical in polar, and broadly elliptic in lateral view, with prominently ridged acrolamella (apical papilla-like laesura) (76.86-)99.54(-120.07) µm long, perispore hyaline, much larger than megaspore, both perispore and epispore thicker around distal pole than at equator, outer sublayer of epispore deeply plicate giving it a finely rugose appearance, inner sublayer of epispore much thinner than outer sublayer, pseudoendospore (intine) evident below exine layer, epispore up to 346 µm in length (excluding acrolamella) and up to 329 µm at equator.
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