262 



THE AMERICAN CHARACIDAE. 



times (Patia Basin) occupying nearly the entire width of the peduncle; young 

 frequently with dark lines following alternate septa between myotomes near 

 to middle line. 



Hmneral spot sometimes with a light border in front and behind, obscured 

 by a vertical band in the young. 



24. AsTYANAX (PoECiLURiCHTHYs) TOTAROENSis Eigenmann. 



Plate 54, fig. 1. 



Astyanax potaroensis Eigenmann, Ann. Carnegie mus., 1909, 6, p. 22; Rcpt. Princeton univ. expcd. 

 Patagonia, 1910, 3, p. 433; Mem. Carnegie mus., 1912, 5, p. 361, pi. 7, fig. 5. 



Habitat. — Potaro River. Guiana. 



Specimens examined. 



Catalogue 

 number 



1037 C. Type 



1038 C, 11733 I. 

 Paratypes 



1039 C. 



1040 C. 



1041 C, 11734 I. 



Number of 

 specimens 



1 



12 



1 

 1 

 o 



Size 

 in mm 



58 

 51-04 



about 59 



45 



47,49 



Locality 

 Amatuk Cataract, Potaro River 



Kanganima, Lower Potaro River 

 Tukeit, Lower Potaro River 

 Erukin, Lower Potaro River 



Collector 

 Eigenmann 



Sliidek^r 



Eigenmann 



Eigenmann 



Evidently aUied to A. bimaculatus and A. orthodus. It is readily distin- 

 guished from A. bimaculatus by its emarginate anal, the broad caudal band, 

 and the absence of any stripe on the caudal peduncle. In the coloration of the 

 sides it approaches A. abramoides, the humeral spot being less well defined, the 

 black lateral line being absent. Its anal is distinctly shorter than that of 

 A. orthodus. 



Head 3.5; depth 2.6-3; D. 11; A. 27 or 28, rarely 29; scales 8 (rarely 9)-37 

 to 38 ^-6 or 7; eye 2.75; interorbital 3. 



Elongate, subrhomboidal, profile rising rapidly in front, then curved more 

 gently to the dorsal; ventral profile regularly rounded. Preventral area convex, 

 without a distinct median series of scales; postventral area narrowly rounded. 

 Predorsal area narrowly rounded, two scales in front of the dorsal, the median 

 line otherwise naked to the occipital process. 



In ten specimens five have 37, three 38, one has 39 and one 41 scales. 



