70 



A 



Fig. 36: Dorsal view of the su- 

 praethmoid of Phoxinus. A: 

 P. phoxinus (CNUC uncat.. 

 76.0 mm TL): B: P. neogaeus 

 (KU 8521. 53.0 mm SL): C: 

 P. en -Thro gast er (KU 5773. 

 51.5 mm SL): D: P. oreas 

 (KU 3259. 55.0 mm SL): E: 

 P. eos (KU12255. 43.0 mm 

 SL). Scale bars = 1 mm. 



Variation of the supraethmoid among Phoxinus species affects its general shape and shape 

 of the lateral and posterior margins. The supraethmoid is short and relatively broad in 

 P. neogaeus, oreas, eos, erythrogaster, and tennesseensis (TS 40[1]); whereas it is elon- 

 gated, relatively narrow, and slender in P. phoxinus, brachyurus, issykkulensis. and cum- 

 berlandensis (TS 40[0]). The middle of the lateral margin of the supraethmoid is convex 

 and forms a small process in P. oreas, eos, brachyurus. and eiythrogaster (TS 4 1 [0] : 

 Fig.36C, D); the lateral margin is straight in P. tennesseensis and neogaeus: it is concave 

 and forms a waist-like structure in P. cumberlandensis, issykkulensis, and phoxinus (TS 

 41 [1]; Fig.36A, E). The concavity at the lateral margin is shallow in P. phoxinus: it is dee- 

 per but narrow in P. cumberlandensis. The posterior margin of the supraethmoid is slight- 

 ly concave in P. oreas; deeply concave in P. phoxinus, brachyurus, eos, and issykkulensis 

 (TS 42[0]); it is not concave in other species (TS 42[1]), among them the posterior mar- 

 gin of the bone is convex in P. erythro gast er, tennesseensis, and neogaeus; it is almost 



