A new formal classification of Gesneriaceae is proposed. It is the first detailed and overall classification of the family that is essentially based on molecular phylogenetic studies. Three subfamilies are recognized: Sanangoideae (monospecific with Sanango racemosum), Gesnerioideae and Didymocarpoideae. As to recent molecular data, Sanango/Sanangoideae (New World) is sister to Gesnerioideae + Didymocarpoideae. Its inclusion in the Gesneriaceae amends the traditional concept of the family and makes the family distinctly older. Subfam. Gesnerioideae (New World, if not stated otherwise with the tribes) is subdivided into five tribes: Titanotricheae (monospecific, East Asia), Napeantheae (monogeneric), Beslerieae (with two subtribes: Besleriinae and Anetanthinae), Coronanthereae (with three subtribes: Coronantherinae, Mitrariinae and Negriinae; southern hemisphere), and Gesnerieae [with five subtribes: Gesneriinae, Gloxiniinae, Columneinae (5the traditional Episcieae), Sphaerorrhizinae (5the traditional Sphaerorhizeae, monogeneric), and Ligeriinae (5the traditional Sinningieae)]. In the Didymocarpoideae (almost exclusively Old World, especially E and SE Asia/Malesia) two tribes are recognized: Epithemateae [with four small, but morphologically and genetically very distinctive subtribes: Loxotidinae (monogeneric with Rhynchoglossum), Monophyllaeinae, Loxoniinae and Epithematinae (monogeneric)] and Trichosporeae (the earliest name at tribal rank for the ‘‘Didymocarpoid Gesneriaceae’’). The last is subdivided into ten subtribes: Jerdoniinae (monospecific), Corallodiscinae (monogeneric), Tetraphyllinae (monogeneric), Leptoboeinae, Ramondinae (Europe), Litostigminae (monogeneric), Streptocarpinae (Africa and Madagascar), Didissandrinae, Loxocarpinae and Didymocarpinae. Didymocarpinae is the largest subtribe (ca. 30 genera and >1600 species) and still requires intensive study. It includes the most speciose genera such as Cyrtandra, Aeschynanthus, Agalmyla, Didymocarpus, Henckelia, Codonoboea, Oreocharis and Primulina and the types of the traditional tribes Didymocarpeae, Trichosporeae and Cyrtandreae.
A New Formal Classification of Gesneriaceae
Genera: Brookea, Jerdonia, Sanango, Titanotrichum