FRESH-WATER FISHES OF SIAM, OR THAILAND 



411 



of all the rivers. It is also common in the Dutch East Indies, and 

 ranges thence to the west coast of India. 



The average length of 20 adult Thailand specimens was 20.5 cm ; the 

 longest, 28.3 and 29.5 cm., were females. 



A specimen, 27 cm. long, taken in the Gulf of Siam off Sriracha June 

 8, 1927, had its left maxillary barbel bifid at the tip. 



Very long and thick dorsal and pectoral spines, coarsely granulated 

 on their anterior surface and serrated behind, characterize this species. 

 The adipose fin is either entirely black or bears a large black spot. 



Figure 91. — Tachysurus caelatus (Cuvier and Valenciennes). Drawn by Luang Masya; 

 courtesy of the Thailand Government. 



The species shares with the related ones the names pla hot and pla uk, 

 with such qualifications as pla hot deng {deng^ red, in allusion to a 

 general reddish color in life), pla hot lueng {lueng, yellow, in allusion 

 to a brassy yellow color of some freshly caught individuals), and pi a 

 uh pah htoang {pah hwang^ wide mouth) . 



TACHYSURUS VENOSUS (Cuvier and Valenciennes) 

 FiGXJEE 926 



Arms venosus CxniEii and Valenciennes, 1840, vol. 15, p. 69 (Rangoon). 

 lachysurns venosus Fowler, 1934a, p. 93 (Bangkok). 



While Tachysurus venosus is of wide distribution (Philippines, 

 Dutch East Indies, Singapore, Malacca, Andamans, Ceylon, and 

 Madagascar), and common in parts of its range, it appears to be rather 

 rare in Thailand. In the large collections made for the Siamese 

 Bureau of Fisheries, the writer obtained the fish at only one locality, 

 at the mouth of the Chantabun Estuary, at Lem Sing, Southeast 

 Thailand, on June 9, 1926, while fishing with a hand line from a row 

 boat; three specimens 21 and 22 cm. long, all mature females were 

 caught. 



