6 ELOPIFORM FISHES 



The standard length (S.L.) of the specimens is taken from the tip of the snout to 

 the anterior margin of the first ural centrum, unless otherwise stated. The frequent 

 displacement of the hypurals in fossil material prevented the use of the more usual 

 limits of this co-ordinate. The length of the head is interpreted as the distance 

 between the tip of the snout and the posterior margin of the operculum. Linear 

 dimensions are expressed in millimetres. Vertebral counts given are exclusive of 

 ural centra and centra incorporated as a functional part of the neurocranium. 

 Lastly, the first caudal vertebra is taken to be that centrum which bears a complete 

 haemal arch and spine. 



III. SYSTEMATIC DESCRIPTIONS 



Cohort TAENIOPAEDIA Greenwood et al. (1967) 



Superorder ELOPOMORPHA Greenwood et al. (1966) 



Order ELOPIFORMES Greenwood et al. (1966) 



Diagnosis. Elopomorph fishes of fusiform shape ; body rounded or compressed, 

 never excessively deepened or elongated. Dorsal and anal fins emarginate, always 

 distinct from the forked caudal fin. Pectoral fins held horizontally, low down on 

 the body ; pelvic fins abdominal. Epaxial trunk musculature never extending 

 onto the cranial roof. Dermethmoid large, overlying a cartilaginous ethmoid. 

 Parietals meeting in the mid-line. Post-temporal fossa with a roof ; subtemporal 

 fossa deep ; pars jugularis long ; jugular vein, hyomandibular branch of VII and 

 orbital artery with separate openings on the lateral face of the prootic. Orbito- 

 sphenoid and basisphenoid well developed. Anterior myodome absent. Para- 

 sphenoid extending to, or near the posterior limit of the neurocranium, with teeth 

 beneath the orbit ; basipterygoid process absent. Otophysic connection, if 

 developed, never with an intimate connection with the ear. Palatine formed by 

 distinct autopalatine (when ossified) and dermopalatine. Circumorbital series with 

 supraorbital, antorbital and six infraorbitals. Rostral ossicles developed. Func- 

 tional part of the upper jaw formed by the premaxilla and maxilla ; supramaxillae 

 present but not capable of independent movement. Mandible with a fossa on the 

 inner surface receiving the A w division of the adductor mandibulae ; retroarticular 

 absent. Gill arches with separately ossified dermal tooth plates and endochondral 

 supports. First suprapharyngobranchial ossified, second suprapharyngobranchial, if 

 present, cartilaginous. Urohyal shallow. Opercular series complete. Pectoral 

 girdle attached to the neurocranium ; mesocoracoid arch, two or three postcleithra 

 and a pectoral splint present. Pelvic splint present. Vertebral column with auto- 

 genous neural arches, haemal arches and parapophyses. Epineural and epipleural 

 intermuscular bones present. Supraneurals forming a complete series between the 

 occiput and the dorsal fin. Caudal skeleton with two free ural centra, the first sup- 

 porting two autogenous hypurals, the second supporting four or five upper hypurals. 

 Uroneurals free from centra. Nineteen principal caudal fin-rays, 17 of which are 

 branched. Scales cycloid, overlapping and marked anteriorly by prominent radii 



