Halictus alphenum Cameron 1897, Mem. Manchester Sot., 41 (4): 108 [male, Mussouri, type in Oxford]; Bliithgen, 1930, Mitt. deutsch. entom. Gesell., 73 (= H. ceylonicus Cameron, 1902); 1931, Zool. Jb. Syst., 61: 301.
Halictus ceylonicus Cameron, 1902, Ann. Mag. Nat. Hist., 9 (7): 253 [female, Ceylon, type in Oxford].
Ceylonicola submicans Friese, 19 18, 2001. Jb. Syst., 41: 504 [male, Ceylon, type in Berlin]; Bliithgen, 1926, Zool. Jb. Syst., 51: 546 (= H. ceylonicus, Cameron, 1902, net 1898, cf. L. (S.) bidentatum p. 17.5).

Halictus aulacophorus Strand, 1913, Arch. Naturgesch., 79A: 137 [female, Hatton, Ceylon, type in Deuts. Entom. Inst., Eberswalde]; Blüthgen 1926, Zool. Jb. Syst., 51: 538 [redescription].

Sudila bidentata Cameron, 1898, Mem. Manchester Sot., 42 (11): 54 [male, Ceylon, type in Oxford]; Cockerell, 1923, Ann, Mag. Nat. Hist., 9 (11): 267 [male].
Sudila fuscipennis Cameron, 1898, Mem. Manchester Sot., 42 (11): 55 [male, Ceylon, type in Oxford]; Cockerell, 1923, Ann. Mag. Nat. Hist., (9) 11: 268 [male]; Bliithgen, 1930, Mitt. deuts. entom. Gesell., 74; Bliithgen, 2001. Jb., Syst., 61: 301 (= Halictus bidentatus Cameron).
Sudila ceylonica Cameron, 1898, Mem. Manchester Sot., 42 (11): 55 [female, Ceylon, type in Oxford]; Cockerell, 1923, Ann. Mag. Nat. Hist., (9) 11: 267 [female]; Bliithgen, 1930, Mitt. deuts. entom. Gesell., 75; Bliithgen, 1931, Zool. Jb., Syst., 61: 301 (= Halictus bidentatus Cameron).
Ceylonicola atra Friese, 1918, 2001. Jb., Syst., 41: 502 [female & male, type in Berlin]; Bliithgen, 1930, Mitt. deuts. entom. Gesell., 75; Bliithgen, 1931, Zool. Jb., Syst., 61: 301 (= Halictus bidentatus Cameron).
Ceylonicola rubriventris Friese, 1918, Zool. Jb., Syst., 19: 503 [female, Ceylon, type in Berlin]; Bliithgen, 1931, Zool. Jb., Syst., 51: 58.5.
Halictus (Sudila) bidentatus: Bliithgen, 1931, Zool. Jb., Syst., 61: 301 (= Sudila fuscipennis Cameron, S. ceylonica Cameron, Ceylonicola atra Friese).

Distribution: endemic to Sri Lanka.

Holotype female: China, Chongqing, Wanzhou District, Wan Er bao Nature reserve, 30°80′N 108°40′E, 1200m, 11 July 1993, Jian Yao (Chinese Academy of Sciences, Beijing).

Halictus jacobsoni Friese, 1914, Tijdschr. Ent., 57: 20 [female, Gunung Gedah, type in Forschungsinstitut Senckenberg, Frankfurt, a. M.]; Blüthgen, 1926, Zool. Jb., Syst., 5 1: 569 [female, redescription].

Halictus (Evylaeus) kandiensis Cockerell, 1913, Entomologist, 46: 34 [female, Kandy, Ceylon; type in Nat. Hist. Museum, London]; Bliithgen, 1931, Zool. Jb. Syst., 61: 330 [female, redescription].

Holotype female: S. India, Nilgiri Hills, Naduvatam, 6000 ft, v. 1958 (P. S. Nathan) (col. Ebmer).

Holotype female: China, Hainan, Baisha County, Nankai Down, 19°13′N 109°42′E, 249m, 21 November 2008, Rui Zhang (Chinese Academy of Sciences,
Beijing).