216 FISHES OF WESTERN SOUTH AMERICA 
Type: Hemibrycon polyodon Giinther 
Trinidad and Colombia to southeastern Peru and Bolivia 
Maxillary teeth (at least in adults) in greater number than in Bryconamericus; 
maxillary slender and reaching to near middle of pupil; head short and body 
elongated; gill rakers of first arch long and setiform. 
Reaching to higher elevations than any other Characin genus, and descending 
to sea level in the North. It is quite possible that the respective species have been 
evolved independently from different species of Bryconamericus or Astyanax. Four 
species have been recorded heretofore from Peru: Hemibrycon ipanquianus by E. D. 
Cope ‘‘dedicated to the memory of the Inca Ypanqui, who in the city of Cuzco on 
the Urubamba, the first of his line, devoted himself to monotheism”’ was taken on 
the Urubamba at 11500 feet; Hemibrycon jelskii (Stemdachner) was recorded from 
Monterico, eastern central Peru, and from the Rio Huambo; Hemibrycon huwam- 
bonicus Steindachner has been recorded from Callacate and the Rio Huambo; and 
Hemibrycon tridens from Uruhuasi in southern Peru. 
240. HEMIBRYCON TRIDENS Eigenmann 
Hemaibrycon tridens Figenmann, 1922, Mem. Carnegie Mus., LX, 152; 
Eigenmann, 1927, Mem. Mus. Comp. Zool., XLIITI, iv, 403, pl. xevi, fig. 3. 
13723, 1, 65 mm., Rosenberg, Uruhuasi, southern Peru. 
241. HEMIBRYCON HELLERI Kigenmann 
Hemibrycon hellert Eigenmann, 1927, Mem. Mus. Comp. Zool., XLII, iv, 406, pl. xevi, fig. 2; 
Pearson, 1937a, Proc. Cal. Acad. Sei., (4), XXIII, 91. 
———, 18, 45-100 mm., the largest the type, Rio Comberciato, Heller, 1915. 
17611, 1, 65 mm., Paipay, Rio Crisnejas, Pearson, 1922. 
16047, , Santa Ana creek, Eigenmann, November, 1918. 
Southern Peru and upper Maranon 
Near H. huambonicus, but pectorals shorter, not reaching ventrals; anal 
shorter; middle caudal rays black; a large, obscure, vertical humeral spot; margin 
of anal dusky; anterior rays of anal with hooks to near the tips in the males. 
242. HEMIBRYCON HUAMBONICUS (Steindachner) 
Tetragonopterus huambonicus Steindachner, 1882 (1883), Denksch. KIx. Akad. Wiss. Wien, XLVI, 
285 Dlaave ules le. 
Hemibrycon polyodon BKigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, IIT, 432. 
Hemibrycon huambonicus Pearson, 1924, Ind. Univ. Studies, no. 64, 42; 
Bigenmann, 1927, Mem. Mus. Comp. Zool., XLIII, 1v, 410, pl. xxxix, fig. 5; 
Pearson, 1937a, Proc. Cal. Acad. Sei., (4), XXIII, 91. 
Mountain slopes on Atlantic side of Peru and Bolivia 
— and 13753, 5 females, 63-100 mm., Rio Comberciato, 1800 feet above sea level, E. Heller, 
September 15, 1915. 
16195, many, 48-119 mm., Huancachupa creek, Hudnuco, Allen, October, 1918. 
