﻿28 



INDIANA UNIVERSITY STUDIES 



Scales tliiii, regiikirly imbricate, witli as many as ten radials ; lateral 

 line complete, nearly straight; anal sheath consisting of a single row of 

 scales along the bases of the anterior rays ; caudal naked except for a 

 basal sheath on the loAver lobe of the male and the peculiar scales just 

 below the middle rays in the male. 



Scales of the back margined with dark ; margins of the myotomes 

 above the anal marked with chromatopliores ; no humeral spot, a silvery 

 band ; a conspicuous black spot on the end of the caudal peduncle, rounded 

 in front, pointed on the bases only of the middle caudal rays; peduncle 

 in front of the spot without chromatophores. Orange in life above and 

 behind caudal spot. 



One specimen from the Calamar Cienega, 32 mm. CM, No. 5105; and 

 three, the largest 30 mm. Soplaviento. CM. No. 5106; I.U.M. No. 12862, 

 may belong to this species. Chromatophores are limited to the dorsal region 

 and to along the base of the anal ; the caudal spot is smaller, oval. 



Hyphessobrycon proteus sp. nov. 



Type, 74 mm. 9 Quibdo. CM. No. 5094. 



Paratypes, over 100. Quibdo. CM. No. 5095 a-z ; I.U.M. No. 12858. 

 Sixty-eight largest 23 mm. Soplaviento. CM. No. 5096; I.U.M. No. 

 12852. 



Fifty-four, largest 45 mm. Calamar. CM. No. 5097 ; I.U.M. No. 12853. 

 Forty-seven, largest 47 mm. Cienega at Calamar. CM. No. 5098; 

 I.U.M. No. 12854. 



Two, Puerta Wilches. CM. No. 5099; I.U.M. No. 12855. 

 One, below Buena Vista. CM. No. 5100. 

 One, 39 mm. Honda. CM. No. 5101. 



Seven, largest 50 mm. Bernal Creek. CM. No. 5102; I.U.M. No. 

 12850. 



One, 30 mm. to base of caudal. Apulo. I.U.M. No. 12857. 



Very similar to Aslyanax rul)errimMS from the San Juan and Dagua 

 rivers from which the preserved specimens with a complete lateral line 

 can only be distinguished with difficulty. Its formal distinguishing features 

 are the smaller number of anal rays and smaller number of scales and the 

 nature of the scales below the lateral line. Although the number of speci- 

 mens available for study is large it is quite possible that additional col- 

 lections from the upper San Juan and Raspadura rivers will throw better 

 light on the relationship of the two species. It is quite certain that the 

 significance of the completeness or incompleteness of the lateral line is 

 subordinate to' that of other characters. The genus HyphessoWycon and 

 Hemigrmmmis are therefore conveniences rather than entities. Certainly 

 as at present defined they are polyphyretic. 



Head 4; depth 2.25-2.66; D. 11; A. /g, /j, ^, the enumer 



ator being the number of individuals. Scales 6 or 7— i,]. |f, ^"j, g?^,— 

 41 to 54 ; ej^e 2.6-2.75 ; equals interorbital ; depth of caudal peduncle 

 equal to its length. 



Compressed, oval ; dorsal and ventral profiles nearly equally curved, 

 only a slight depression in the profile over the eyes; preventral area 

 narrow, rounded, without a distinct median series of scales ; or with 



