Bryologist 63: 43. 1960.
Plants delicate, in creeping mats. Stems with branches 0.4–0.6 mm, 0.7–1 mm across leafy branch, main-stem and branches arching upward, stem and branch apices with penicillate group of abruptly imbricate leaves. Leaves 0.5–0.7 mm; margins incurved distally to form tubulose apex; supra-alar cells short. Specialized asexual reproduction rare, by filamentous gemmae. Perigonia on branches. Perichaetia on stems or branches. Seta red. Capsule 0.4–0.6 mm; annulus absent; exostome teeth 16, lanceolate, finely striate, longitudinally furrowed; endostome basal membrane wide, segments equal to exostome teeth length, cilia 1, short, occasionally rudimentary. Calyptra smooth. Spores spheric, 13–14 µm, slightly roughened.
Phenology: Capsules mature summer.
Habitat: Rotten logs, tree bark, charred wood, moist live-oak hammocks
Elevation: low elevations (0 m)
Distinctive gametophytic traits of Acroporium smallii include long-ovate leaves with erect margins, linear medial laminal cells, and alar cells much inflated and sharply differentiated from more distal cells. The species is confined to Miami-Dade County.
"equal" is not a number.