Appendix 1.

Voucher information for five populations of S. alterniflora used in this study. All vouchers are deposited at the Herbarium of National Sun Yat-Sen University.

Voucher no.	Collection locality	Geographic coordinates
Shi 091105	Fuzhou, Fujian, China	26°01′04″N, 119°37′19″E
Xia 110401	Mipu, Hong Kong, China	22°29′45″N, 114°02′47″E
Xia 110411	Nantong, Jiangsu, China	32°33′96″N, 121°01′67″E
Xia 110415	Chongming, Shanghai, China	31°36′21″N, 121°49′85″E
Shi 101015	Taibei, Taiwan, China	25°07′34″N, 121°27′30″E