Achalinus Peters, 1869

Hou, Shao-Bing, Wang, Kai, Guo, Peng, Chen, Jin-Min, Yuan, Zhi-Yong & Che, Jing, 2021, Two new species and a new country record of the genus Achalinus (Reptilia Squamata: Xenodermidae) from China, Zootaxa 4950 (3), pp. 528-546 : 544

Key to species of the genus Achalinus Peters, 1869

1a. Internasal absent..................................................................................... 2

1b. Internasal present..................................................................................... 3

2a. Ventrals 146–155 in male; subcaudals 39–60; DSRM 19–21........................................ A. meiguensis

2b. Ventrals 160 in male; subcaudals 73; DSRM 23............................................... A. panzhihuaensis

3a. Loreal absent........................................................................................ 4

3b. Loreal present....................................................................................... 6

4a. Dorsal scale rows 27–27–25................................................................. A. formosanus

4b. Dorsal scale rows 23–23–23............................................................................ 5

5a. Suture between internasals longer than prefrontal suture......................................... A. jinggangensis

5b. Length of suture between internasals subequal to that between prefrontals............................ A.pingbianensis

6a. Anterior temporals single; two superior posterior temporals in contact and overlap greatly posterior to parietal....................................................................................................... A. hainanus

6b. Anterior temporals 2; two superior posterior temporals not in contact with each other posterior to parietal, or in contact but overlap slightly...................................................................................... 7

7a. Suture length between internasals less than or subequal to that between prefrontals................................. 8

7b. Suture length between the internasals much longer than that between prefrontals.................................. 10

8a. Dorsal scale rows 25–25–23...................................................................... A. niger

8b. Middorsal scale rows 23............................................................................... 9

9a. Dorsal color brown in adults, ventral light brown; TaL/ToL 18–20%................................. A. yunkaiensis

9b. Dorsal color black, ventral black brown; TaL/ToL 15–25%............................................ A. spinalis

10a. Infralabials 5....................................................................................... 11

10b. Infralabials 6....................................................................................... 12

11a. Ventrals 157–161 in females; subcaudals 63–65..................................................... A. emilyae

11b. Ventrals 148–158 in females; subcaudals 54–61.................................................... A. rufescens

12a. Subcaudals 47–70; TaL/ToL 19–22%................................................................ A. ater

12b. Subcaudals 82; TaL/ToL 26%............................................................... A. yangdatongi