No abstract

Dissochaeta is a plant genus of woody climbers, classified in the tribe Dissochaeteae (Melastomataceae). The taxonomic history of the genus is complicated and includes some allied genera like Dalenia, Diplectria, Macrolenes and Omphalopus. Most of them are already regarded as synonyms of Dissochaeta except for Macrolenes which is considered a separate genus here as well. Dissochaeta is characterised by its scrambling habit, interpetiolar outgrowths, 4-merous flowers, dimorphic stamens and berry-like fruits. A taxonomic revision of Dissochaeta is presented, which includes references, a complete list of synonyms, detailed morphological descriptions of the species and an identification key, as well as information on the distribution, habitat and ecology, vernacular names, notes and lists of examined specimens. Fifty four species and two varieties of Dissochaeta are recognised. We designate several lectotypes, propose eleven new combinations and we describe one new species and one new variety.

Eleven new species ofCyrtandra(Gesneriaceae) from Sulawesi are described and illustrated:C. albifloraKarton. & H.J.Atkins,C. boliohutensisKarton. & H.J.Atkins,C. gambutensisKarton. & H.J.Atkins,C. hekensisKarton. & H.J.Atkins,C. hendrianiiKarton. & H.J.Atkins,C. hispidulaKarton. & H.J.Atkins,C. kinhoiiKarton. & H.J.Atkins,C. multinervisKarton. & R.Bone,C. nitidaKarton. & H.J.Atkins,C. rantemarioensisKarton. & R.Bone andC. rubribracteataKarton. & H.J.Atkins. Illustrations, maps and preliminary conservation assessments are provided for all the species.

The Dissochaeta alliance (= subtribe Dissochaetinae) is a group of woody climbing taxa within tribe Dissochaeteae (Melastomataceae) and comprises 90 species mainly distributed in Southeast Asia. The circumscription of the alliance and its genera has been problematic when based on only morphological characters. With a broad sampling of relevant taxa, this study aims at a natural circumscription of and revised generic delimitation within this alliance. A molecular phylogeny based on two nuclear (nrETS, nrITS) and four chloroplast (ndhF, psbK‐psbL, rbcL, rpl16) markers confirmed the non‐monophyly of Dissochaeteae s.l. Taxa traditionally placed in Dissochaeteae are found in three lineages in distant positions within Melastomataceae. The Medinilla alliance is resolved within Sonerileae + Oxysporeae, while the monophyletic Dinophora/Ochthocharis lineage forms a polytomy with Marcetieae, Melastomateae, Microlicieae, and Rhexieae; and the well‐supported Dissochaeta alliance is sister to Cambessedesieae. Based on the molecular results, Dissochaeteae is redefined to exclude the Medinilla alliance and Dinophora/Ochthocharis. It consists of six successively branching major clades, which we treat as six genera, Pseudodissochaeta, Creochiton, Dalenia (Dissochaeta sect. Dalenia), Diplectria (Dissochaeta sect. Diplectria), Macrolenes and Dissochaeta s.str. To avoid a paraphyletic Dissochaeta, Dalenia and Diplectria are resurrected, Macrolenes is expanded to include the Dissochaeta rostrata complex, and a narrowly circumscribed Dissochaeta s.str. is adopted. A re‐investigation of morphological characters based on herbarium material provides support of newly defined taxa. Two sections for Macrolenes are newly proposed, and two sections of Dissochaeta s.str. are maintained. Important morphological traits such as habit and floral characters are discussed to show the morphological support for each delimited genus and the establishment of a new classification of the tribe.