Petrocodon tongziensis (Gesneriaceae), a new species from limestone areas in Guizhou, China based on morphological and molecular Evidence
26 September 2018
Zhang, Ren-Bo; Deng, Tan; Fu, Long-Fei; Li, Shu; He, Lin; Dou, Quan-Li; Wen, FangPetrocodon tongziensis R.B.Zhang & F.Wen, a new species from the northern Guizhou province, China, is described and illustrated based on molecular and morphological evidences. The new species was found growing in the crevices and tufa of moist surfaces of limestone hills in Tongzi County, Guizhou province, China. The maximum parsimony (MP) analysis on the combined DNA regions of ITS and trnL-F shows that the new species falls into the large polytomy within Petrocodon and is discovered most closely to an unidentified species (WF2014) and both of them seems to be as sister to Petrocodon hunanensis X.L.Yu & Ming Li. This is congruent to the morphological character that four fertile stamens were co-existed in the clade of new species and Pet. hunanensis, which likely to be the ancestral character distinguishing to other clades within Petrocodon. Since it is unlikely to compare the new species to the unidentified species without any morphological information, we therefore compare the new species to its most closely species Pet. hunanensis by different morphologies of terrestrial stems, bract numbers, bracteoles numbers and shape, lobes shapes of the upper lip, staminode numbers and length.