79 



A 



FIC 



Fig.42: Lateral view of orbi- 

 tosphenoid. pterosphenoid, 

 prootic, and parasphenoid of 

 Phoxinus. A: P. neogaeus 

 (KU 8521. SL 53.0 mm): B: 

 P. erythrogaster (KU 5773. 

 SL 51.5 mm I; C: P. oreas 

 (KU 3259. SL 55.0 mmmm): 

 D: P. eos (KU 12255. SL43.0 

 mm). Scale bars equal 1 mm. 



pterosphenoid forms the anterior part of the hyomandibular fossa, and its posterior mar- 

 gin forms the anterior part of the trigeminal foramen. 



The pterosphenoid is irregularly shaped in Phoxinus. A process is present at its anterior 

 margin in P. eos, erythrogaster. and phoxinus (TS 64[ 1 ] ): the process is absent in other 

 species of the genus and in the outgroups (TS 64[0]). The posterior margin of the ptero- 

 sphenoid bears a notch which forms the anterior part of the trigeminal foramen. The po- 



