FRESH-WATER FISHES OF SlAM, OR THAILAND 277 



HOMALOPTERA LINEATA, new species 

 FiGtJKE 55 



DescHftiori. — Depth about 6.75 in standard length ; head 4 in length, 

 its width 1.5 in its length and 1.3 times its depth; eye in middle of 

 head comparatively large, 3.5 in head, 1.3 in snout, and equal to the 

 flat interorbital space; barbels very slender, inner rostral about 0.3 

 diameter of eye, outer rostral somewhat longer, maxillary about 0.5 eye. 



Squamation: Lateral line complete; scales deficient on abdomen; 

 scales in lateral line 37, in transverse series from midline of back to 

 base of ventral fin 8.5-1-5; predorsal scales 21; circumpeduncular 

 scales 14. 



Fins: Origin of dorsal fin posterior to origin of ventrals, verj^ 

 slightly nearer to base of caudal fin than to tip of snout; depth of 

 body % height of dorsal fin, dorsal rays ii, 7 ; caudal fin about length 

 of head, deeply emarginate, lobes pointed ; anal rays i, 6, origin of fin 

 nearer to base of caudal than to base of ventrals ; ventrals shorter than 

 pectorals, not reaching anal opening, rays ii, 7 ; pectorals shorter than 

 head, extending to ventrals, rays vi, 10. 



jjy h^^' ■ "'^'^•'-^'^^'-^- ^^\-';'l35l 



Figure SS.—Homaloptera lineata, new species: Type (U.S.N.M. No. 119488). Drawn by 



Mrs. Alice C. Mullen. 



Coloration : A narrow reddish-brown band along lateral line from 

 head to base of caudal fin; body and head otherwise whitish; fins 

 hyaline, unmarked. 



Type aiid paratype.— The type (U.S.N.M. No. 119488) , 2.7 cm. long, 

 was collected by H. G. Deignan in the Mekong at Chiengsen Kao, 

 Northern Thailand, January 12, 1937. A paratype 2.4 cm. long 

 (U.S.N.M. No. 119489) was taken at the same place and time. 



Remarks. — The relationship of this species to the other members of 

 the genus found in Thailand is sufiiciently indicated in the foregoing 

 key. This form is distinguishable from various other species of the 

 East Indian Archipelago, Burma, and India, by its relatively few 

 scales in the lateral line, fin formulae, and distinctive coloration. 



590087—45 19 



