Populus × berolinensis K.Koch nothovar. jrtyschensis (Chang Y.Yang) C.Shang

Shang, Ce, Zhang, Limei & Zhang, Zhixiang, 2016, New combinations for nothotaxa of Populus (Salicaceae) from China, Phytotaxa 253 (2), pp. 176-178 : 176

Populus × berolinensis K.Koch nothovar. jrtyschensis (Chang Y.Yang) C.Shang comb. & stat. nov.

Basionym:— Populus × jrtyschensis Chang Y.Yang in Wang & Dong (1982: 112). Parental taxa: Populus laurifolia Ledebour × Populus nigra Linnaeus var. nigra .

Type:— CHINA. Xinjiang Uygur Autonomous Region: Ertix River, Beitun , s. dat, Yang Chang-you 755787 ( holotype: XJA not seen) .

Populus × jrtyschensis was described for a natural hybrid species distributed aside Ertix River. While the name was originally published, the multiplication sign ‘×’ was added ahead of the epithet ( Wang & Dong 1982), declaring its hybridity. Its parents were then indicated to be P. laurifolia and P. nigra based on the transitional morphology characters between putative parent species ( Yang 1992, 2012), and molecular evidence supporting this hypothesis was provided from a DNA barcode research ( Feng et al. 2013). However, the parentage statement of P. × jrtyschensis would make it a synonym of P. × berolinensis . Populus × berolinensis was described from Berlin and was thought to be a hybrid between P. laurifolia and P. nigra var. italica . Although it is in a rank inappropriate in relation to that hybrid formula (Art. H.5.2 of ICN), P. × berolinensis is nevertheless the correct name applicable to all hybrids between P. laurifolia and P. nigra (Art. H.5 Note 1 and Ex. 1 of ICN). Hence we propose a new combination for P. × jrtyschensis ( Fig. 1A ).

Figures

FIGURE 1. Correct names in the appropriate rank and their parentage for nothotaxa of Populus in Flora of China. A, P.×berolinensis = P. laurifolia × P. nigra, P.×berolinensis nothovar. berolinensis = P. laurifolia × P. nigra var. italica, P.×berolinensis nothovar. jrtyschensis = P. laurifolia × P. nigra var. nigra; B, P.×xiaohei = P. nigra × P. simonii, P.×xiaohei nothovar. xiaohei = P. nigra var. nigra × P. simonii, P.×xiaohei nothovar. gansuensis = P. nigra var. thevestina × P. simonii, P.×xiaohei nothovar. xiaozhuanica = P. nigra var. italica × P. simonii.