81 



gaeus, erythro gaster, brachyurus, eos, and in the outgroups, only a very small portion of 

 the pterosphenoid articulates with the parasphenoid (TS 66[0]). A much larger portion of 

 the pterosphenoid sutures with the wing of the parasphenoid in other species of Phoxinus 

 (TS 66[1]). 



Otic Region 



Located posteriorly to the orbital region, the otic and occipital regions form the otic cap- 

 sule. Bones in the otic region include parietal, medial extrascapula, sphenotic, prootic, 

 epioccipital, intercalar, pterotic, and lateral extrascapula. All are paired bones. 

 Parietal and medial extrascapula (Fig.44A-B). In cyprinids, the parietal is a paired 

 dermal bone located at the posterodorsal portion of the neurocranium, and forms the po- 

 sterodorsal cover of the braincase. The parietal sutures with the frontal anteriorly, sphen- 

 otic anterolaterally, pterotic posterolaterally, supraoccipital and epioccipital posteriorly. 

 The left and right parietals suture each other mesially with a small overlap at its middle 

 and posterior portion. Length of the parietal is usually about 30-50% of the frontal length 

 (Howes 1981). A parietal fontanelle exists between the parietal and frontal in some 



C 



Fig.45: Sphenotic of Phoxi- 

 nus. A: P. oreas (KU 3259. 

 SL 55 mm, ventral view); B: 

 P. eos (KU 12255, 43.0 mm 

 SL, ventral view); C: P. pho- 

 xinus (CNUC uncat., 76.0 

 mm TL); D: P. cumberlan- 

 densis (KU 18934, 52.0 mm 

 SL) (a: dorsal view; b: ventral 



D view). Scale bars = 1 mm. 



