FRESH- WATER FISHES OF SIAM, OR THAILAND 133 



IMekong and Meiiam Mun in the Eastern region; and from various 

 streams in the Chant abiin-Krat district of Southeastern Thaihmd. 



Under the influence of freshets in coastal rivers, this species may 

 go into the Gulf of Siam. Thus, on October 30, 1923, in a trap well 

 off the mouth of the Tachin River, a number of examples of this fish 

 were taken, and two, 12.6 and 13.6 cm. long, were preserved. 



Examples in excess of 50 cm. long have been met with in Thailand, 

 hut with the increase in fishing activity such large fish are becoming 

 scarcer. The usual size of adult specimens in recent years has been 

 20 to 30 cm. A length of 70 cm. is reported for the Indo-Australian 

 Archipelago by Weber and de Beaufort. 



Figure 14. — Hampala macrolepiaota van Hasselt. Drawn by Luang Masya; courtesy 

 of the Thailand Government. 



This is one of the most strikingly colored and most readily recog- 

 nized of all the local cyprinoids. Adult or nearly full-grown speci- 

 mens always show, on a silvery background, a blackish band or blotch 

 extending from the base of the anterior dorsal rays nearly or quite to the 

 base of the ventrals, and a conspicuous blue-black band along the upper 

 and lower margin of each caudal lobe, the remainder of the caudal 

 fin as well as the dorsal being bright red. The mouth is large, the 

 maxillary reaching to or somewhat beyond a vertical from the front 

 border of the eye, and there is a maxillary barbel as long as the diam- 

 eter of the eye. A male fish, 22.5 cm. long, taken in the inner lake of 

 the Tale Sap October 9, 1923, had, in addition to orange-red caudal and 

 lower fins, the entire head and all the body scales thickly beset with 

 minute pearllike excrescences. 



The young exhibit a number of dark markings not seen in the adult. 



The dorsoventral blotch is always present but may be reduced to 

 an oblong or round spot across or above the lateral line; tliere are 



590087—45 10 



