﻿ICHTHYOLOGICAL RECONNAISSANCE OF COLOMBIA 



25 



A vertical humeral spot, widest and most intense over the lateral 

 lines. A silvery lateral band, expanded at the end of the caudal peduncle ; 

 no spots or bands on the fins. 



Astyanax ruberrimus sp. nov. 



Closely allied to /i. fischeri Steindachner, differing chiefly in its notably 

 greater depth. 



Type, 107 mm. Istmina. CM. No. 4912. 



Paratypes, several hundred, largest 113 mm. Istmina. CM. No. 

 4913 a-o ; I.U.M. No. 12751. 



Paratypes, 7, largest 113 mm. Half way between Puerto Negria and 

 Istmina. CM. No. 4914; I.U.M. No. 12752. 



Paratypes, many, largest 94 mm. Puerto Negria. CM. No. 4915 a-z ; 

 I.Ti.M. No. 12753 a-z. 



Paratypes, 95, largest 93 mm. Cordova on the Dagua. CM. No. 5093 

 a-z ; I.U.M. No. 12857. 



Head about 4 ; depth 2.2-2.75 ; D. 11 ; A. 23-28 ; scales 7 or 8-35 or 36- 

 7 or S (6 in Rio Dagua) ; eye 3 in the head; interorbital 2.4-2.5. 



Deep and robust, ventral profile a little more arched than the dorsal, 

 and a little more regular ; preventral area broad, slightly flattened, with 

 about 14 scales not in a distinct median series; postventral area rounded; 

 predorsal area keeled, with 10 or 11 median scales. 



Occipital crest about four in the distance from its base to the dorsal, 

 bordered by three or four scales on each side ; interorbital smooth, convex ; 

 frontal fontanel narrow, about half as long as the parietal without the 

 groove; naked margin around the free border of the second suborbital 

 about one-fourth as wide as the suborbital ; maxillary equals snout, four 

 in the head; three or four teeth in the outer series of the premaxillary. 

 five in the inner ; one or two broad-tipped maxillary teeth ; mandible with 

 four or five large teeth and about seven small ones on the side. 



Gill-rakers 7 + ]1. 



Origin of dorsal equidistant from tip of snout and caudal or a little 

 nearer the former, its anterior rays 3.4 in the length ; caudal about 3.5 in 

 the length ; anal slightly emarginate, its highest ray equals length of head 

 without snout, its origin behind the vertical from the last dorsal ray ; 

 ventrals reaching anal and pectorals the ventrals in the young, not reaching 

 anal and ventrals in the adult. 



Scales everywhere regularly imbricate except at least in Istmina speci- 

 mens between the anal and the first row of scales below the lateral line; 

 one or two rows of interpolated scales causes the series in a triangle above 

 the anal to be deflected toward the anal ; ten, more or less radii ; caudal 

 naked ; a series of low scales along the base of the anterior anal rays ; 

 lateral line nearly straight. 



The specimens from the Dagua river have the lateral line more de- 

 curved than the rest. 



A conspicuous black spot occupying the entire width of the caudal 

 peduncle in the young, somewhat narrower in the adult, not continued on 

 the middle rays; a faint vertical humeral spot. Base of dorsal yellow, 

 shading into brick red ; middle of caudal yellow, the rest brick-red ; base 

 of anal brick-red. 



