ANATOMY OF THE MELANONIDAE 



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Fig. 9. A-C Melanonus zugmayeri: A, palatoquadrate, hyosymplectic and opercular bones of 130mm specimen in medial view, light hatched 

 area represents ligamentous system connecting opercular bones to hyomandibular; B, palatine of 100mm specimen, right side, lateral view; 

 C, hyomandibular, left side, of 100mm SL specimen in anterior view showing foramen for hyoid branch of facial nerve (arrowed) and 

 lateral flange; D, Percopsis omiscomayus , palatine and pterygoids in lateral view (heavy dotting indicates cartilage). 



metapterygoid process are present in macrouroids, bathyga- 

 dids and macruronids (Howes & Crimmen, 1990; Howes, 

 1991b). Reduction of the entopterygoid and metapterygoid 

 appears to be characteristic of supragadoids (Howes, 1990). 

 Amongst ophidiiforms the metapterygoid abuts against the 

 lower limb of the extended anterior portion of the hyoman- 

 dibular. 



The quadrate (Fig. 9A) of Melanonus has a wide angle 

 between its posterior border and the posteroventral spine. 

 The size of this angle is variable among gadiforms and 

 appears correlated with the orientation of the suspensorium. 

 An 'interosseuos space' between the symplectic and preoper- 

 culum (Okamura, 1970; 1989) is also a condition of the 

 angular separation of the two parts of the quadrate, being 

 absent where the angle is small (Howes, 1990). 



Hyoid arch (Figs. 9-11) 



The hyomandibular (Fig. 9A) has, as in all gadiforms, a single 

 articulatory condyle. The bone is narrow-waisted with the 

 relatively long shaft oval in section, a foramen for the hyoid 

 branch of the facial nerve pierces its posterior margin (Fig. 

 9C). Posteriorly is a long, horizontal process which articulates 

 with the opercle. The lateroposterior face contacts the border 

 of the preopercle. Medially a band of ligamentous connective 

 tissue joins the shaft with the opercular process and a wider 

 band runs at right angles to it to attach to the subopercle and 

 interopercular-subopercular ligament (Fig. 9A). 



The course of the hyoid branch of the facial nerve is 

 partially exposed laterally, due to attrition of the outer part of 

 the hyomandibular, part of which remains as a lateral flange 

 which is a common feature (synapomorph) for gadiforms, 



