Plants amphibious or aquatic. Rhizomorphs buried to 20 mm below substrate, dark brown, globose, to 5 mm tall, to 14 mm in diameter, 3-lobed, lobes weakly developed, with a large number of simple or dichotomously branched roots borne along rhizomorph fossae, roots pale to dark brown, with or without root hairs, root hairs borne on trichoblasts, if phyllopodia present then mostly less than 3 mm long, dark brown to black, glossy, centrally thinly crustaceous, marginally thinly chartaceous, arrested lycophyll primordia not observed. Lycophylls caespitose, herbaceous, erect, to 50 per plant, acicular, to 130 mm long, to 4.5 mm wide at spathulate base, with dorsilateral hyaline alae to 1 mm wide extending to 30 mm along the base of lycophyll, alae decrescent to obtuse; subulae pale to dark green, subulate, to 105 mm long, terete higher up, to 2.5 mm in diameter above the alae, convex abaxially, shallowly sulcate adaxially, gradually tapering to an acicular apex; epidermal cells at basal part of lycophylls oblong with near straight anticlinal walls, cells towards the lycophyll apices oblong to square, with near straight to slightly curved anticlinal walls, regularly with a single or more rows of narrower and longer epidermal cells above peripheral fibre strands; stomata absent or present, if present then in up to 4 rows along lacunae, often confined to the lycophyll apex, guard cells (40-)53(-70) µm long, mostly surrounded by small, irregularly shaped epidermal cells; hypodermal collenchyma absent; peripheral fibre strands present, mostly 3 in abaxial part of lamina, opposite lacuna walls, more numerous and smaller towards lycophyll apices; cuticle thin, faintly longitudinally striate; translacunar septae more than one cell layer thick, aerenchyma cells with short arms, pores triangular; intrastelar canals 1 to 3; lacunae without idioblasts; ligules membranous, hyaline, ovate-auriculate to deltoid, to 2.6 x 1.8 mm, central cushion papillate, margins fimbriate; labia acute; velae complete, or rarely with an opening < 0.5 mm in diameter at lycophyll base, cells polygonal in outline, with near straight to strongly curved anticlinal walls. Sporangium sack cells oblong to rectangular, near straight to gently curved, the anticlinal walls gently curved. Sporangia with brown walls, without strengthening cells, cells stacked, elongate, with near-straight to gently curved transverse walls; megasporangia elliptic in frontal view, to 4 x 2.5 mm, frontal face margins rounded; microsporangia unknown. Megaspores dimorphic, chalk-white to pale grey when dry, blackish when wet, tetrahederal-globose, with a broad equatorial ridge and laesura, the proximal and distal faces with low verrucae, the larger spores (472-)492(-536) µm in equatorial diameter, the smaller spores (296-)339(-424) µm in equatorial diameter; microspores unknown. Chromosome number: unknown.
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