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epioccipital with a posterior laminar extension, broadly sutured with expanded 

 parapophyses of fifth and sixth vertebrae; hyomandibula separated from 

 metapterygoid by broad lamina of quadrate; vomer without anterolateral processes; 

 urohyal with anterodorsal spur extending between paired hypohyals; nasal 

 bifurcated, with anterolateral ossified branch; first two hypobranchials concave and 

 oriented anteriorly along medial margin; first epibranchial enlarged dorsomedially 

 and overlapping second epibranchial; first infraorbital posterior to lacrimal flared 

 anteriorly. 



Genus Tetranematichthys Bleeker 



Generic Synonymy 



>- 



Ageneiosus Kner 1858a (type species: Ageneiosus quadrifilis by original description). 



Tetranematichthys Bleeker 1858 (replacement name; type species: Ageneiosus 

 ^fld/T/z/w, by original designation and monotypy). 



Diagnosis ■ 



The genus Tetranematichthys differs from all other members of the 

 Ageneiosidae by the retention of a single pair of mental barbels in adults. Further 

 distinguished from confamilials by a combination of the greater body depth; very 

 elongate, edentulate maxillary barbels in nuptial males; a fatty middorsal keel 

 between the dorsal fins; swimbladder large and with a single, fleshy, posterior 

 caecum; caudal fin truncate, with 8+10 principal rays, and relatively few (8-11) 

 lower procurrent rays; presence of a short postcleithral process, shared only vnthA. 

 brevis; and the unusually dark, cryptic coloration. Apart from these differences, 



