342 BULLETIN 188, UNITED STATES NATIONAL MUSEUM 

 KRYPTOPTERUS HEXAPTERUS (Bleeker) 



Silurus Jiewapterns Bleekeb, 1851 (45), p. 203 (Bandjermassing, Borneo). 

 Micronema hexapterus Bleekek, 1865 (356), p. 175 (Siam). — Sauvage, 1881, p. 161 



(Siam) ; 1883b, p. 154 (Menam Chao Phya). 

 Cnjptopterus hexapterus Weber aud de Beiaufoet, 1913, vol. 2, p. 222 (Siam). 

 Kryptopterus hexapterus Fowler, 1934a, p. 87 (Cbiengmai, Chiengseii, Bangkok) ; 



1934b, p. 337 (Bangkok) ; 1935a, p. 98 (Bangkok) ; 1937, p. 137 (Bangkok) ; 



1939, p. 43 (Krabi). 



Collections made for the Siamese Bureau of Fisheries contain speci- 

 mens of this species from the Menam Chao Phya at Bangkok, Sep- 

 tember 12, 1923, and the lower Bangpakong River, July 1, 1923, and 

 June 26, 1933 ; these specimens were from 14.5 to 19.0 cm. long. The 

 fish taken from the Bankpakong in 1923 had the band of vomerine 

 teeth with an indentation medianly on both anterior and posterior 

 sides, while in the second specimen from the same stream the vomerine 

 teeth were normal, that is, lacking anj^ such indentation. Fowler 

 extended the range to the Meping at Chiengmai and the Mekong at 

 Chiengsen. A specimen in the British Museum from the Siamese 

 Museum came from the Menam Chao Phya. The further distribution 

 of the species includes Sumatra, Borneo, and Java. 



KRYPTOPTERUS MOOREI, new species 

 FiGUBE 78 



Description. — Body strongly compressed, comparatively deep, its 

 depth at origin of anal fin 3.8 in standard length; least depth of 

 caudal peduncle equal to snout ; head moderately depressed, its length 

 5.8 in standard length, its width 1.5 in its length; dorsal profile of 

 head and anterior part of back regularly concave, posterior 0.8 of 

 back nearly straight ; eye in midlength of head, its center in line with 

 cleft of mouth, 4.2 in head, 1.75 in snout, 3 in the strongly convex 

 dorsal interorbital space, 2 in the ventral interorbital space; jaws 

 equal ; maxillary extending halfway between tip of snout and posterior 

 border of eye; maxillary barbels 1.25 times length of head, reaching 

 to midbase of pectorals; mandibulary barbels 0.75 length of head; 

 vomerine teeth in a short, straight, elliptical band about 0.6 length 

 of eye. 



Fins: Caudal deeply forked, equal to length of head; anal well 

 separated from the caudal, the rays 66 ; ventrals short, about one-third 

 pectorals, rays i, 7 ; pectorals about length of head, the rays i, 13, the 

 spine weak and very slightly ossified. 



Coloration: Plain. 



Type and paraty pes. —The type (U.S.N.M. No. 109787) 23.5 cm. 

 long was collected in a small klong off the Menam Chao Phya, near 

 Paknampo, Central Thailand, November 26, 1923. One of the para- 

 types, obtained at the same time and place, is 17 cm. long. (Paratypes, 

 TT.S.N.M. Nos. 109671, 109672, 109786.) 



