27 



SOCA 



Fig.6: Part of the supraorbital 

 canal (in black), and nasal, 

 lateral ethmoid, frontal, and 

 supraorbital bones in hemitre- 

 mians and in the outgroup. A: 

 Nocomis platyrhynchus (KU 

 18926, 46.5 ramSL); B: He- 

 mitremia flammea (KU 

 18931, 57.4 mm SL); C: 

 Couesius plumbeus (KU 

 18881, 65.0 mm SL); D: Pho- 

 xinus erythrogaster (KU 

 5773, 62.0 mm SL). Scale 

 bars = 1 mm. 



is very short (Fig.4A). In Rhynchocypris, the rostral process is long and well-developed 

 (Fig.4B), especially in ripe females (Howes 1985). The process is also present in Tribo- 

 lodon hakonensis, but the process in this species is less developed than that in Rhyn- 

 chocypris (Cavender & Coburn 1992). The long fleshy rostral process was interpreted by 

 Howes (1985) as an apomorphy for the genus Rhynchocypris. (This elongated rostral pro- 

 cess is also present in Rhinichthys, Coburn 1994, pers. comm.). - TS 1: Fleshy rostral 

 process very short [0], or long [1]. 



