Key to Oxynoemacheilus species from the Göksu, Seyhan, Ceyhan and Orontes rivers, plus coastal drainages within their bounds.

1a Suborbital groove absent in male......................................................................... 2

1b Suborbital groove present in male........................................................................ 5

2a Caudal fin slightly emarginate, almost truncate................................................... O. seyhanensis

2b Caudal fin deeply emarginate or forked.................................................................... 3

3b Lateral line incomplete, terminating anterior to dorsal-fin origin or slightly behind dorsal-fin base............. O. cilicicus

3a Lateral line terminating behind dorsal-fin base, at caudal-fin base in some individuals............................... 4

4a Caudal fin deeply emarginate, length of middle caudal-fin ray 1.2–1.3 times in length of longest unbranched ray in upper caudal-fin lobe; head length 25–27% SL; body depth at dorsal-fin origin 18–20% SL; caudal peduncle depth 1.4–1.6 times in its length................................................................................... O. ceyhanensis

4b Caudal fin slightly forked, length of middle caudal-fin ray 1.3–1.5 times in length of longest unbranched ray in upper caudalfin lobe of; head length 21–24% SL; body depth at dorsal-fin origin 16–20% SL; caudal peduncle depth 1.2–1.4 times in its length....................................................................................... O. namiri

5a A bold upper and lower black blotch or spot on caudal-fin base...................................... O. seyhanicola

5b One bold central blotch or no bold black blotch on caudal-fin base, often an irregularly-shaped black bar at caudal-fin base.. 6

6a A yellowish triangle at upper and lower posteriormost portions of caudal peduncle; caudal peduncle depth 1.4–1.9 times in its length; flank in juveniles with a midlateral series of horizontally elongate blotches, adults with a brown marbled pattern................................................................................................. O. hamwii

6b No yellowish triangles at posteriormost portion of caudal peduncle; caudal peduncle depth 1.9–2.5 times in its length; flank with a midlateral series of irregularly-shaped bars or vertically-elongate roundish or squarish blotches.................. 7

7a Flank posterior to dorsal-fin base and caudal peduncle with a series of bold, usually vertically-elongate, roundish or squarish blotches; blotches on back usually separated from blotches on flank, if connected, reaching slightly below midlateral flank; caudal peduncle depth 2.1–2.5 times in its length.................................................. O. samanticus

7b Flank posterior to dorsal-fin base and caudal peduncle with a series of bold, usually irregularly-shaped bars reaching from dorsal midline almost to ventral midline; caudal peduncle depth 1.7–2.1 times in its length...................... O. evreni