86 



somewhat prominent, with a strong symphysial hook, fitting 

 into a groove of the upper jaw. Barbels 4 or 2. Eye with a 

 free orbital margin. Praeorbital pentagon, third suborbital 

 broad, nearly entirely covering the cheek. Short dorsal with 

 7 branched rays, far back, without strong spines, its posterior 

 rays opposite to anal, which is short and has 6 branched 

 rays. Ventrals originating far before dorsal. Pectorals longer 



Fig. 32. Luciosoma trinema (Blkr.) X V*- 

 a, Symphysial part of lower jaw with knob fitting in a groove of the upper jaw. 



than head. Caudal deeply forked. The last dorsal and anal 

 spine and the outer ventral ray may be produced into a long 

 filament. Scales of moderate size, lateral line curved down- 

 wards, running along the lower part of body and tail. Pseudo- 

 branchiae present. Gillrakers extremely short, widely set. 

 Pharyngeal teeth uncinate in 3 series 5.4.2 2.45 or 4.4.2 2.4.4. 

 Branchial opening reaching to below eye. 



Distribution: Indo- Australian Archipelago (Sumatra, Java, 

 Borneo). Siam and Indo-China. 



Artificial key to the species. 



1. Barbels rudimentary L. trinema p. 86. 



2. Barbels well developed. 



1. A black longitudinal band from snout to upper lobe 

 of caudal. Origin of dorsal above 23 rd 24 th scale 



of lateral line L. setigerum p. 87. 



2. A longitudinal series of black blotches from head 

 continued as a band to end of middle caudal rays. 



Origin of dorsal above 2O th scale of lateral line . . . Z. spilopleura p. 89. 



i. Luciosoma trinema (Blkr.). 



Leudscus trinema Bleeker, Nat. Tijdschr. Ned. Indie III. 1852, p. 600. 

 Luciosoma (Trinematichthys) trinema Bleeker, Ichth. Arch. Ind. Prodr. II. Cyprini, 



1860, p. 416. Atl. Ichth. III. 1863, p. 132. 

 Luciosoma trinema Giinther, Cat. Brit. Mus. VII. 1868, p. 199. 



