104 



ONTOGENY AND SYSTEMATICS OF FISHES-AHLSTROM SYMPOSIUM 



L L- 



Fig. 56. (Upper.) Anterior portion of Myrophis punclalus larva depicting typical myrophin gut morphology. Abbreviations: LL|_j, liver lobes 

 1-3; GB, gall bladder. (Lower.) Anterior portion of Neenchelvs microlrelus larva depicting gut morphology. Abbreviations: LL,.,, liver lobes 1- 

 2; GB. gall bladder. 



to a basal plate which ossifies from the hypohyal to the bifur- 

 cation of the ligament. The urohyal of the Ophichthinae gen- 

 erally ossifies to include a spike which extends well posterior to 

 the area of the bifurcation. 



The gill openings of the Myrophinae are midlateral and con- 

 stricted. Ophichthine gill openings are variable in position, their 

 major axis ranging from midlateral to ventral, but always un- 

 constricted. 



Leptocephali belonging to five of the nine myrophin genera 



have been identified. Larvae of four of these five genera have 

 three unconnected liver lobes with the gall bladder on the third 

 lobe (Fig. 56-upper). Larvae of the fifth genus, Neenchelvs. which 

 differ trenchantly from all other ophichthid larvae, have two 

 unconnected liver lobes with the gall bladder on the second lobe 

 (Fig. 56-lower). Leptocephali belonging to twenty of the forty- 

 four ophichthin genera have been identified. All twenty of these 

 genera have two connected liver lobes with the gall bladder on 

 the second lobe (Fig. 57-upper). 



