The abundant Sundaland forest frog, Rana chalconota, has long been considered a single widespread species, although some authors have recommended its division into regional subspecies. The discovery of co-occurring pairs of morphologically distinct populations in three widely separated parts of the range led to a morphological and molecular analysis of populations from all parts of the known range. The results suggest that R. chalconota consists of at least seven species from Thailand through Borneo and Java. Existing names are applied to three of these species, R. chalconota (Schlegel), R. raniceps (Peters) and R. labialis Boulenger. We describe four others as new species and suggest the existence of one or two additional, unnamed species. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155, 123–147.