FRESH-WATER FISHES OF SIAM, OR THAILAND 195 



Bay of Bengal. The only other habitat is the Mekong in Cochinchina 

 and Cambodia, and, inferentially, in Laos. 



In recording this species from Thailand as well as from Cochinchina 

 and Cambodia, Sauvage (1881) described a specimen 20 cm. long and 

 noted that the type of the species, in the Museum of Natural History 

 in Paris, was collected at "Pexabury" by Bocourt. It is not a matter 

 of great importance, but it may be pointed out that the five specimens 

 that Bleeker (1865 [360]) had in hand when he first described and 

 named the species were stated to be from Bangkok and Ayuthia. 



The usual length of adult fish taken in Central Thailand is 13 to 

 15 cm,, but examples up to 20 to 21 cm. are not rare, and a number 

 22 to 22.5 cm. have been observed, representing about the maximum 

 size known to be attained. In the Mekong basin in Eastern Thailand 

 this fish regularly reaches a larger size than has been met with else- 

 where. Examples over 30 cm. long are common, and in such the 

 anterior dorsal rays are greatly elongated and falciform. This fea- 

 ture was once thought by the writer (Smith, 1929) to be of specific 

 significance and the name Puntioplites falcifer was given to the fish 

 so characterized. At the present time, however, with the information 

 available, it is not possible to consider the greatly developed dorsal 

 fin as more than an age or size character. 



Fishermen are able to recognize this fish at once by its large, 

 serrated anal spine, and in most places give it a special name, pla 

 kamang^ heard throughout Central Thailand and also along the Mun 

 River in Eastern Thailand, sometimes shortened to yla mang (as in 

 Bung Borapet) . Vernacular names of rather local usage are pla Ham 

 (angular fish) at Paknami^o, pla wi at Chiengrai, and pla pae at 

 Bandon. 



Genus CHAGUNIUS H. M. Smith 



Chagunius H. M. Smith, Proc. Biol. Soc. Washington, vol. 51, p. 157, 1938. (Type, 

 Cyprimis chagunio Hamilton.) 



CHAGUNIUS CHAGUNIO (Hamilton) 



Cyprinus chagunio Hamilton, 1822, pp. 295, 385 ("The Yamuna, and in the nprth,- 

 ern rivers of Behar and Bengal"). '"*■' '''■ ";'^'^'' 



Chagunius chagunio Smith, 1938a, p. 157 (India, Burma, Siam). ' ' ' 



This very interesting and strongly characterized species, first given 

 a definite scientific status by Hamilton in 1822 and later recognized as 

 having a wide range over northern India, was added to the Thai fauna 

 by collections made by H. G. Deignan in October 1936, in the Salwin 

 at Ta Fang and in the Huey Mekong Kha, a tributary of the Salwin, 

 at the base of Doi Mekong Kha. The Thai specimens, three in num- 

 ber, have been compared with specimens collected by Dr. S. L. .Hora at 

 Dehra Dun, in the Punjab, India, and found to agree. '"'^ ''"'"^ 



