Tuesday, December 25, 2018

[Botany • 2018] Rachunia cymbiformis • A New Genus and Species of Gesneriaceae from Thailand


 Rachunia cymbiformis D.J.Middleton.

Rachunia D.J.Middleton & C.Puglisi gen. nov.
in Middleton, Khew, Poopath, et al., 2018.  

Abstract 
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 boat‐shaped bracts in the inflorescence, free and imbricate sepals, short and campanulate corolla, clavate stigma, and relatively robust orthocarpic fruit.

Keywords: phylogeny, Henckelia, Didymocarpinae


Rachunia cymbiformis D.J.Middleton. close-up of bracts and flower.
Photo by Manop Poopath. 

Rachunia D.J.Middleton & C.Puglisi gen. nov. 

Type species: Rachunia cymbiformis D.J.Middleton. 

Etymology: The genus is named in honour of the Thai botanist Dr Rachun Pooma of the Forest Herbarium Bangkok (BKF) to recognise his great contribution to our understanding of plant diversity in Thailand and the wider region.


Rachunia cymbiformis D.J.Middleton sp. nov. 

Etymology: The specific epithet ‘cymbiformis’ refers to the boat-shaped bracts in the inflorescence.


D. J. Middleton, G. S. Khew, M. Poopath, M. Möller and C. Puglisi. 2018. Rachunia cymbiformis, A New Genus and Species of Gesneriaceae from Thailand. Nordic Journal of Botany. 36(11); e01992. DOI: 10.1111/njb.01992