Plants 0.1--0.4 cm, dark-green to brownish. Stem leaves oblong-lanceolate to oblong-ovate, 0.5--1.3 mm, acute and abruptly apiculate; margins irregularly serrulate at apex or sometimes entire; brood bodies elliptic to subcylindric, without longitudinal septae, of 3--5 cells. Sporophyte not known.

Trunks of deciduous trees in dry oak-hickory climax zone; N.C., Mo.

This variety is restricted to the southern Appalachians and Ozark Mountains. It differs from its closest relative, Z. viridissimus var. rupestris, by its small size and serrulate distal leaf margins.