LEIBY: OPHICHTHIDAE 



103 



Family Ophichthidoe 



Subfomily Myrophmoe 



Sub fomily Ophichthmae 



I— II 



Ttib« 



Myrophin 



Tribe 

 Ophichthini 



Tribe 

 Sphogebranchir 



Tribe 

 Basconichthyini 



Tribe 

 Callechelyini 



o = •) 

 w ^ tt 



-o ^ •» ly 



Callechelyin 

 Ancestor 



Bosconichf hy s-like 

 Ancestor 



Moderately Specolized 

 Optiictittiin-like Ancestor 



oderotely Speciolized 

 Ophictttttin-like Ancestor 



Moltfolioptiis Or 



E vips- like Ancestor 



Ouossiremus-like Ancestor 



Ance strol Myroph 



Ancestrol Optlictlttlin 



= Tribe BenThenchelyin 



Congrid-like Ancestor 



Fig. 55. Hypothesized relationships of the subfamilies and genera of the eel family Ophichthidae. 



tin having instead a hardened tail tip with, at most, a few ru- 

 dimentary caudal rays embedded in the flesh of the tail. The 

 monotypic genus Leptenche/ys. known only from the 1 1 5 mm 

 type specimen, has caudal-fin rays, but they are weakly devel- 

 oped compared to those of a myrophin (McCosker, 1977). Since 

 all ophichthid larvae have a well-developed caudal fin until the 

 onset of metamorphosis, the presence of weakly developed rays 

 in the only known specimen of Leplenchelys may be an anomaly 

 resulting from incomplete resorption during metamorphosis. 

 The well developed caudal fin of Echelus has prompted most 

 earlier authors to place it in the family Echelidae (=Ophichthi- 

 dae, in part) or to ally it with the subfamily Myrophinae (e.g.. 

 Dean, 1972; Blache, 1977); however, the osteology of the genus 

 (McCosker, 1977) and its larval morphology (Blache, 1977: Figs. 

 72 and 74) clearly place Echelus in the subfamily Ophichthinae 

 and ally it with the tribe Ophichthini. 



Adult Myrophinae have four to seven branchiostegal rays 

 attached to the epihyal and ceratohyal and 1 3-45 free (unat- 

 tached) branchiostegal rays which originate posterior to the tips 



of the epihyals. Most adult Ophichthinae have the majority of 

 their branchiostegal rays attached to the epihyal and ceratohyal. 

 The free branchiostegal rays of all Ophichthinae originate an- 

 terior to the tips of the epihyals. 



The ceratohyal, epihyal and hypohyal of both the Myrophinae 

 and the Ophichthinae originate from a single block of cartilage 

 with the first center of ossification being a thin strip along the 

 lateral face of the cartilage (Leiby, 1979a, b; 1981). When de- 

 velopment is complete, the ceratohyal of the Myrophinae is a 

 simple bone which terminates about midpoint along the lateral 

 face ofthe epihyal (Dean, 1972; McCosker, 1977; Leiby, 1979b). 

 The ceratohyal ofthe Ophichthinae has a slender, elongate distal 

 portion which terminates about midpoint along the lateral face 

 of the epihyal and a medial portion which is attached to the 

 proximal end ofthe epihyal by a cartilage (McCosker, 1977; 

 Leiby, 1981). 



The urohyal ofthe Myrophinae and Ophichthinae ossifies in 

 a bifurcated medial ligament which is attached to the developing 

 hypohyals. In the Myrophinae, the urohyal is generally limited 



