Vanmanenia Hora 1932

Key to the species of the barred group of Vanmanenia

1 Gill opening larger, its upper angle aligned with the middle point of the eye...................................... 2

- Gill opening smaller, its upper angle level with the lower edge of the eye (Lancang-jiang drainage (the upper Mekong River))........................................................................ Ƒanmanenia microcephala, sp. nov.

2 Patch of the caudal-fin base connected to the upper and lower margin of the caudal peduncle........................ 3

- Patch of the caudal-fin base dissociated and not connected to the upper and lower margin of the caudal peduncle (the main stream and branches of the Yuan-jiang drainage (the upper Red River))........................... Ƒanmanenia striata

3 Dorsal part of head covered with a large black blotch; dorsal part of the body with 4–5 black saddles.................. 4

- Dorsal part of head covered with several dark brown vermiculations; dorsal part of the body with 5–7 black saddles...... 5

4 In adult (approximately larger than 30 mm SL), width of bars on flank smaller than the diameter of the eye (Nanla-he, Xishuangbanna in Yunnan, China and Nam Ou and Nam Tha basins in northern Laos, all belonging to the Mekong River basin)............................................................................ Ƒanmanenia serrilineata

- In adult (approximately larger than 30 mm SL), width of bars on flank equal to the diameter of the eye (Nam Xam and Nam Ma basins in Laos belonging to the Mekong River basin).................................. Ƒanmanenia crassicauda

5 Caudal fin almost truncated; anus located between the pelvic-fin insertion and anal-fin origin (Zhangjiu-he in Luquan County, Yunnan, flowing into the Pudu-he, a right branch of Jinsha-jiang drainage [upper portion of the Yangtze River])........................................................................................... Ƒanmanenia pseudostriata

- Caudal fin concave; anus located at anterior one third between pelvic-fin insertion and anal-fin origin (Lixian-jiang drainage [the upper Song Da or Black River, a main tributary of the Red River]).......................... Ƒanmanenia tetraloba