Rachunia cymbiformis, a new genus and species of Gesneriaceae from Thailand

Rachunia, a new genus of Gesneriaceae from Thailand, is described with a single species, Rachunia cymbiformis. Its relationship to the rest of subtribe Didymocarpinae is investigated through a phylogenetic study based on Bayesian Inference and Parsimony analyses of nuclear ITS and plastid trnL-trnF (intron-spacer) sequences. Morphologically, Rachunia differs from the related genera Codonoboea in the large boat-shaped bracts and orthocarpic vs plagiocarpic fruit; from Microchirita in the bracts, wiry vs fleshy stem, the campanulate vs tubular corolla and the clavate vs chiritoid stigma, and from  Henckelia in the clavate vs chiritoid stigma, large boatshaped bracts in the inflorescence, free and imbricate sepals, short and campanulate corolla, clavate stigma, and relatively robust orthocarpic fruit.