Key to species of Gobio in Turkey

1a 8–12 scales between posterior extremity of pelvic-fin base and anus.............................................. 2

1b 4–8 scales between posterior extremity of pelvic-fin base and anus.............................................. 6

2a Diameter of scales on belly approximately equal to pupil diameter...................................... G. insuyanus

2b Diameter of scales on belly clearly smaller than pupil diameter.................................................. 3

3a Scales on breast extending to isthmus...................................................................... 4

3b Scales on breast slightly or not extending beyond a line between pectoral-fin origins................... G. microlepidotus

4a Head length 25–27% SL...................................................................... G. hettitorum

4b Head length 27–29% SL................................................................................ 5

5a Distance between anus and anal fin origin 5–7% SL................................................ G. intermedius

5b Distance between anus and anal fin origin 7–8% SL............................................... G. maeandricus

6a Postorbital length 1.3–1.6 times in snout length................................................. G. kizilirmakensis

6b Postorbital length 0.9–1.3 times in snout length.............................................................. 7

7a Interorbital distance 1.6–2.2 times in eye diameter; pelvic fin not reaching behind anus in females; head profile behind nostrils markedly convex...................................................................................... 8

7b Interorbital distance 1.0–1.6 times in eye diameter; pelvic fin reaching behind anus in females; head profile behind nostrils straight or slightly convex............................................................................... 9

8a Body depth at dorsal-fin origin 23–26% SL..................................................... G. gymnostethus

8b Body depth at dorsal-fin origin 18–22% SL........................................................... G. baliki

9a Breast naked or incompletely scaled, if breast scaled, scales extending forward to level of pectoral fin origin; snout pointed, not or slightly concave anterior to nostril...................................................................... 10

9b Breast completely scaled, scales extending to isthmus; snout rounded, distinctly concave anterior to nostril.............. 11

10a Head length 28–30% SL..................................................................... G. kovatschevi

10b Head length 24–26% SL....................................................................... G. artvinicus

11a 4–5 scales between posterior extremity of pelvic-fin base and anus; interorbital distance 1.1–1.3 times in eye diameter................................................................................................. G. bulgaricus

11b 6–8 scales between posterior extremity of pelvic-fin base and anus; interorbital distance 1.4–1.6 times in eye diameter............................................................................................... G. sakaryaensis