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1 Stems prostrate, the leaves on the upper and lower side differentiated; rhizophores borne throughout the length of the stem; leaves borne in pseudowhorls of 8
..2 Apical hair-tip of the leaves twisted-contorted, 1.2-1.7 mm long (sometimes deciduous); strobili 3-6 mm long, 1.5-2 mm wide; leaves 0.15-0.3 mm wide, the marginal cilia absent, toothlike, or as much as 1/6 as wide as the leaf blade; budlike “arrested” branches present
....3 Stems mostly creeping or turned up at the apex, forming mats 1.5-4 cm high; rhizome or rhizomatous stem absent; aerial roots present all along the stems; budlike “arrested” branches absent
......4 Leaves of the underground (rhizomatous) stems not scalelike; rhizophores mostly aerial; sporophyll base pubescent; leaf and sporophyll apices often pubescent
........5 Leaves mostly tightly appressed; leaf bases conspicuously pubescent; strobili distinctly larger in diameter than the subtending stem; sporophyll apex often recurved
........5 Leaves mostly loosely appressed; leaf bases usually glabrescent; strobili not distinctly larger in diameter than the subtending stem; sporophyll apex usually straight