Appendix 1.

Location information for populations of Stipa breviflora and six other Stipa species used in this study.^a

Species	Collection locality	Altitude (m)	Geographic coordinates	N
Stipa breviflora Griseb.	Wulate Middle Banner, Inner Mongolia	1321	41°29′28.63″N, 108°57′17.64″E	12
S. breviflora	Jungar, Inner Mongolia	1160	39°46′8.43″N, 110°57′25.91″E	12
S. breviflora	Gaolan, Gansu	1784	36°15′55.94″N, 103°48′44.18″E	12
S. breviflora	Hainan, Qinghai	2956	36°18′59.32″N, 100°33′43.37″E	12
S. breviflora	Alxa, Inner Mongolia	1461	39°50′39.65″N, 105°03′34.30″E	12
S. breviflora	Chifeng, Inner Mongolia	576	42°38′22.48″N, 119°12′14.24″E	12
S. breviflora	Pulan, Tibet	3863	30°16′33.28″N, 81°10′11.19″E	12
S. breviflora	Hejing, Xinjiang	2141	42°54′05.90″N, 86°17′56.83″E	12
S. aliena Keng	Haibei, Qinghai	3201	101°19′31.3″N, 37°36′38.9″E	5
S. bungeana Trin.	Hohhot, Inner Mongolia	1040	40°47′24.11″N, 111°28′7.28″E	5
S. gobica Roshev.	Wuhai, Inner Mongolia	1599	39°37′51.50″N, 106°53′43.77″E	5
S. grandis P. A. Smirn.	Manzhouli, Inner Mongolia	659	49°33′01″N, 117°33′59″E	5
S. krylovii Roshev.	Hulunbuir, Inner Mongolia	930	47°51′58″N, 115°46′48″E	5
S. purpurea Griseb.	Tianjun, Qinghai	3195	37°12′40.2″N, 98.55′31.4″E	5

Note: N = numbers of individuals sampled.

^aVoucher specimens were not collected at the time of the study.