1 Sporophytes present, the leaves linear, 10-60 cm long and 1-3 mm wide

  2 Spores tetrahedral; paraphyses with an enlarged terminal cell, medium to dark brown; leaf blades 1.5-2 mm wide at the widest point; rhizome scales 4-6 mm long, lacking an elongated hair tip

  2 Spores bilateral; paraphyses filiform, light brown; leaf blades 2-3 mm wide at the widest point; rhizome scales 6-7 mm long with long hair tips 1/3 to 1/2 the scale length

1 Gametophytes only present.

    3 Gemmae of uniform length, each with 4 body cells; epiphytic on tree bark; [known in our region from se. LA]

    3 Gemmae of variable length, with 2-16 body cells; epiphytic or epipetric; [relatively widespread in our region].

      4 Gemmae with 2-12 body cells (with at least some present with 2-3 body cells); end cells of gemmae often swollen and larger than the medial cells; rhizoid primordia often absent on 1 or both end cells, seldom present on medial cells; sporophytes apparently not produced; [epipetric on moist rocks, usually on grotto ceilings in humid gorges or near waterfalls]

      4 Gemmae with 4-16 body cells; end cells of gemmae equal to or smaller than the medial cells; rhizoid primordia regularly present on the end cells, as well as on some medial cells; sporophytes frequently produced (and small sporophytes often present in largely gametophytic colonies); [usually epiphytic, rarely on rocks]