J Syst Evol ›› 1983, Vol. 21 ›› Issue (3): 306-318.

• Research Articles • Previous Articles     Next Articles

An Analysis of the Topoclinal Variation of Lespedeza bicolor Turcz.

Hsu Ping-Sheng, Li Xue-Yu, Gu De-Xing   

  • Published:1983-08-18

Abstract: Owing to the diagnostic characters used for distinguishing Lespedeza bicolor Turcz. from its allies L. formosa (Vogel) Koehne and L. elliptica Benth. ex Maxim. etc. beiny totally quantitative, and the great variability found in themselver as well, the group is therefore regarded as a taxonomically perplexing one. Therefore quantitative measurements of the diagnostic characters, namely, the lengths of flowers (including standards and keels) and calyces (including calyx teeth and tubes) upon the total 307 herbarium sheets collected from 22 provinces and autonomous regions were made, and the data obtained were treated statistically (Table 1) and compared using methods of scatter diagram (Fig. 1--5),polygraph (Fig. 6) and topoclinal variation (Fig. 7--10) in order to bring to light the differentiation pattern of these characters correlated to geographical distribution. The diagrams of topoclinal variation (Fig. 7--10) of single characters represented by the lengths of calyx-teeth and corolla, or the calyx-teeth/calyx-tube ratio, between which exists a strong positive correlation, show a tendency of increasing gradation from northeast towards south-west. But the different combinations of morphological characters as shown in the scatter diagrams and more particularly in the polygraphs, make it possible to divide the Lespedeza bicolor group into the following three geographical types: (1) Bicolor type, with the distributional area of four provinces and one autonomous region of north-eastern and northern China; having the shortest (shorter than the calyx-rube) calyx-teeth of the whole group; with the standards of 71% herbarium materials exceeding the keels; the corolla length/calyx length ratio being 2.24; (2) Formosa type, with the distributional area covering six provinces and one autonomous region of eastern, south-eastern and southern China; with calyx-teeth nearly as long as calyx-tuges; with the keels of 69% herbarium sheets exceeding the standards, including all from whole Guangdong (Kwantung) and Guangxi (Kwansi); the corolla length/calyx length ratio being 2.59, the largest among the group; (3) Elliptica type, with the largest distributional area occupying ten provinces of south western, central, northwestern and eastern China and with most complicated morphological variation; the range of calyx-teeth length being 1.23--5.53 mm; with the keels of 80% herbarium sheets exceeding the standards, including all from whole Hubei (Hupeh) and Sichuan ( Szechuan ). Since the above geographical types are either transitional or overlapping, it is probably appropriate to regard them as different geographical subspecies of a single species Lespedeza bicolor Turcz. Taxonomic treatments are then made herewith. A comparison of the main diagnostic characters and distributional patterns of the three subspecies in question is given in Table 3.