Collette and Gillis: Osteological differences between two species of Crammatorcynus 



29 



Figure 17 



Palatine tooth patches in Grammatorcynus. 

 (a) G. bilineatus, Queensland, 521 mm FL; (b) 

 G. bicarinatus. Western Australia, 765 mm 

 FL. 



Figure 18 (right) 



Left suspensoria in mesial view, (a) Scomberoirwrus 

 semifasciatus, New Guinea, 510 mm FL, 2.5 x ; (b) Acan- 

 thocybium solandri, Revillagigedos Is., 1068mm FL, 

 1.5 x; (c) Grammatorcynus bilineatus, Marshall Is., 

 424mm FL, 2x. 



morus (Fig. 18a). The shank is longer in 

 Acanthocybium than in the other two gen- 

 era. The posterior edge of the ectoptery- 

 goid (from the tip of the dorsal process to 

 the tip of the ventral process) relative to 

 the ventral distance is long, 63-72% in 

 Grammatorcynus, and relatively shorter in 

 Acanthocybium (41-47%) and Scombero- 

 morus (43-63%). 



Entopterygoid The entopterygoid 

 is elongate and oval in shape (width 35- 

 41% of length, Collette and Russo 1985b: 

 fig. 28). The outer margin of the entop- 

 terygoid is the thickest part of the bone 

 and attaches to the inner margin of the ec- 

 topterygoid. The entopterygoid also con- 

 nects with the palatine anteriorly and the 

 metapterygoid posterolaterally. The 

 mesial and posterior borders are free from 

 contact with other bony elements. The 

 dorsal surface is roughly convex. The dorsal surface 

 is similarly convex in Acanthocybium, but the dorsal 

 surface in Scomberom^rcnis is concave. The ventral sur- 



HYOMANDIBULA 



METAPTERYGOID 



face is convex in all three genera, and it forms the 

 major part of the buccal roof. Scomberomonts contains 

 species that have both narrower (S. commerson, width 



