Octoblepharum is a perennial, turf-forming moss genus distributed throughout the tropics and subtropics. We have examined the distribution of genetic variation revealed through randomly amplified polymorphic DNA (RAPD) markers within and between three Octoblepharum species, O. albidum, O. cocuiense and O. pulvinatum, in Panama. We discovered that Octoblepharum populations possess a considerable amount of genetic variation. A plausible explanation for the observed pattern of genetic variation is that each colony, which consists of one genet (clone) in most cases, has often been founded sexually but has then become an isolated, clonally propagating "minipopulation." Genetically independent colonies inhabiting the same area form a more loosely organized "metapopulation" rather than a regular, tightly connected population.

Key words: Bryophyta, genetic variation, Octoblepharum, population genetics, RAPD