1 ^ , - • 200 



Body naked, without dermal plates or scutes, moderately elongate and 

 strongly compressed from behind pectoral fin to base of tail. Body depth greatest at 

 dorsal fin origin, gradually tapered to middle of caudal peduncle. Body width 

 greatest at origin of pectoral spines, least at middle of caudal peduncle. Lateral line 

 ,'»> on body consisting of a midlateral central canal, with numerous short rami, directed 

 posterodorsally and posteroventrally, and bifurcated at the base of the caudal fin, 

 with a long, branched ramus extending onto each lobe of the fin. 



Head large, broad, and strongly depressed. Eyes moderately large, 

 ventrolaterally placed, slightly recessed in orbits and visible in ventral profile. Optic 

 nerve displaced laterally and obliquely across the upper surface of the adductor 

 mandibulae musculature. Orbital rim entire, covered with thick integument that is 

 confluent with skin on head. Eye frequently invested by adipose tissue, especially 

 along anterior and posterior margins. Skin on head relatively thin, smooth, covered 

 with minute tastebuds. Snout moderately long, mouth weakly to strongly inferior. 

 Gape moderately to very broad, usually exposing a portion of the premaxillary teeth. 

 Lips generally thin. Nares widely separated, each surrounded with a very low fleshy 

 fold. A deep groove above the upper lip at each comer of the mouth, beginning just 

 behind the maxilla, extending slightly beyond edge of premaxillary, and curving 

 around and beneath the comer of dentary for a short distance anteriorly. Maxillary 

 barbels of females and nonbreeding males short, filiform, lying concealed within 

 aforementioned rictal grooves. Maxillary barbel of nuptial males extending to 

 corner of eye or beyond, with a bony core formed from an ossified extension of the 

 maxilla, and with several sharp, anterodorsally curved protuberances on upper 

 margin. Barbels on chin present only in small juveniles, consisting of a single pair 

 positioned posterolaterally, about even with the front margin of the eye in most 

 species, and another pair situated anteromedially, near the apex of the dentary; 

 barbels completely resorbed or reduced to very minute stubs in adults, and with no 



