No.23  MICHAEL MÖLLER

Transfer of Tremacron hongheense to Oreocharis (Gesneriaceae)

Phytotaxa 239 (3)：295—296.

ARTICLE

The genus Oreocharis Bentham (1876: 1021) was redefined on the basis of molecular phylogenetic studies (Möller et al. 2011a, b) to include species of ten additional, mostly small-sized and monotypic genera of Chinese Gesneriaceae: Ancylostemon Craib (1920[“1919”]: 233), Bournea Oliv. in Hooker (1893: t. 2254), Briggsia s. str. Craib (1920[“1919”]: 236), Dayaoshania Wang (1983: 319), Deinocheilos Wang (1986: 1), Isometrum Craib (1920[“1919”]: 250), Opithandra Burtt (1956: 162), Paraisometrum Wang in Weitzman et al. (1998[“1997”]: 431), Thamnocharis Wang (1981: 485), and Tremacron Craib (1918: 217). It is now florally one of the most diverse genera in Old World Gesneriaceae besides the enlarged Petrocodon s. l. Hance (1883: 167) (Weber et al. 2011).

In a series of recent studies, more than half of all the ca. 100 species recognized in the extended genus Oreocharis have been analyzed (Möller et al. 2011a, b, Chen et al. 2014). In all of these analyses the expanded Oreocharis forms a highly supported clade in which the species interrelationships run across traditional generic boundaries. In none of the studies do species of Tremacron form a single clade, but fall in two (Möller et al. 2011a,b) or three clades with high branch support thus rendering the genus polyphyletic within a monophyletic Oreocharis (Möller et al. 2011a, b, Chen et al. 2014).

Cai et al. (2015) have recently published a new species in Gesneriaceae from Southeastern Yunnan, China, Tremacron hongheense Chen & Shui (2015: 734). The authors were aware of the expanded Oreocharis and have chosen not to follow it likely due to the morphological similarity with species hitherto belonging to Tremacron. However, this genus is not monophyletic and to reflect natural relationships in the classification, T. hongheense has to be transferred to Oreocharis. In the light of the available published data and in the absence of contradicting published data I accept the enlarged genus Oreocharis and the transfer of Tremacron hongheense to Oreocharis is made here.(Cited from Möller et al., 2015).