The genus Pentalepi F.Muell., resurrected by Karis et al. in 1993, with two species, after being for many years included in Moonia Arn or Chrysogonum L., has been studied morphologically across its full range. Four new species (P. linearifolia Orchard, P. grandis E.W.Cross, P. kakaduensis E.W.Cross and P. walcottii E.W.Cross) are described, as well as three subspecies in P. trichodesmoides F.Muell. (subsp. trichodesmoides, subsp. hispida Orchard and subsp. incana Orchard), two in P. linearifolia (subsp. linearifolia and subsp. nudibranchoides Orchard) and two in P. ecliptoides F.Muell. (subsp. ecliptoides and subsp. hirsuta Orchard), bringing the total to six species and eight subspecies. All taxa are keyed, described, illustrated and mapped.