158 



Mouth small, slightly subterminal and oblique: mouth gape not extending to below the 

 anterior margin of the orbit. Lower jaw slightly shorter than the upper one. 

 Bony interorbital space wide, its width 1 1 9^ of orbit length and 32% of head length. An- 

 terior nasal opening smaller and shorter than posterior nasal opening, the former about 

 half the size of the latter. Entire margin of anterior nasal opening erect: margin of po- 

 sterior nasal opening, except its anterior part, not erect. 



In young individuals (25.3 mm standard length), axis of olfactory organ very short, oval 

 in shape, and situated in anterior part of olfactory chamber: five primary lamellae present. 

 In larger specimens (60.1 mm standard length), the axis elongated and extending to po- 

 sterior portion of organ chamber: up to 16 primary lamellae present. Numerous melano- 

 phores present on primary lamellae in young, on both primary lamellae and axis in adult. 

 Body slender, not strongly compressed. Maximum body depth 20% of standard length. 

 Caudal peduncle short and high, its length 26% of standard length, its depth 36% of its 

 length. 



In male, the genital papilla spheric in shape, and smaller than that in female. Surface of 

 papilla smooth without small skin fold, but one large skin fold present in some specimens. 

 Genital orifice large. Posterior projection of genital papilla well-developed, its posterior 

 end far from origin of anal fin. 



In female, genital papilla well-developed, its posterior margin with few well-developed 

 projections: a long projection extending from posterior of papilla, reaching anal fin ori- 

 gin. Surface of papilla bearing developed skin folds. 



Pectoral fin fan-like in male, sharper and smaller in female, its posterior margin reaching 

 origin of pelvic fin in adults: 14-16 fin-rays. Origin of pelvic fin farther forward than ori- 

 gin of dorsal fin. and in anterior half of standard length; prepelvic length 47% of stan- 

 dard length; eight rays. 



Dorsal fin originating behind pelvic origin, predorsal length 56% of standard length, and 

 120% of prepelvic length: with two procurrent rays, eight fin-rays. Anal fin originating 

 below insertion of dorsal fin; with two procurrent rays and eight rays. Caudal fin deeply 

 forked, lobes sharp: with 11 or 12 dorsal procurrent, 9-10 ventral procurrent rays, and 19 

 (10+9) principal rays. 



Scales covering whole body, weakly embedded on lateral and dorsal surface of body, but 

 deeply embedded on ventral side of the body. 



Left and right supratemporal canals separated from each other, with four pores each side. 

 Otic canal with five pores. Supraorbital canal without interruption, except the region bet- 

 ween nasal and frontal bones, with nine pores. Infraorbital canal with 10 pores. Preo- 

 percular canal with eight pores. Mandibular canal with four pores. Body lateral line 

 complete, extending to caudal fin base, number and positions of the pores varying indi- 

 vidually; about 82 lateral line pored scales. 



Pharyngeal bone robust: its pitted surface broad with four large fossae. Posterior limb 

 elongate, slender and straight; anterior limb slender, narrowing posteriorly, expanding 

 anteriorly, bearing a notch at anterior end. Pharyngeal teeth very strong, hooked at tip. in 

 two rows. 2,4-5.2. 1,5-5.2. 1.4-5.1. Teeth in main row more developed than those on minor 

 row. Masticatory surface of teeth round and smooth. 



