Metzgeriaceae
Thalli with a narrow midrib and a unistratose lamina; prostrate, erect, or pendent, dichotomously branched, rarely pinnate, sometimes with ventral branches. Hairs usually present on the thallus margins, on the underside of the midrib, and sometimes on the thallus surface. Midrib with large epidermal cells, without central strand. Ventral scales lacking. Gametoecia on highly abbreviated branchlets scattered along the ventral side of the midrib, antheridia inside a globose sac, archegonia hidden under a thallus flap. Pseudoperianth lacking. Capsules spherical to ovoid, 4-valved, walls 1-2 layered. Spores small. Elaters with 0-1 spirals, attached to the valve apices.