(Contributions from the Zoological Laboratory of Indiana University, 



No. Ul.) 



25. The Gymnotidae of Trans-Andean Colom- 

 bia and Ecuador 



By Carl H. Eigenmann and Homer G. Fisher 



Ellis (Mem. Carnegie Mus.. VI, 1913, pp. 109-195, plates XV-XXIII), 

 gives a detailed account of the known distribution, S3monomy, and bibliog- 

 raphy of the Gyninotidae. It appears that four species of this family, Gym- 

 notus carapo Linnaeus, Sternopygus macrurus (Bloch and Schneider), Eigen- 

 mannia virescens (Valenciennes), and Hypopornm brevirostris (Steindachner) , 

 have been recorded from the area under consideration and from Central America 

 to the north of it. These four species are more widely distributed than any 

 other Gymnotids. They are the only species found in the Rio San Francisco 

 and they are all foimd in the Orinoco river or in Guiana, in the Amazon, in 

 Uruguay or Southeastern Brazil, and in the La Plata basin. 



Gymnotus carapo reaches the farthest north, being foimd in the rivers 

 aid lakes of both slopes of Guatamala. It has recently been recorded from the 

 Rio San Juan of Trans-Andean Colombia by Regan (Ami. Mag. Nat. Hist. 

 (8) XII, 1914, 466). 



Sternopygus macrurus was recorded by Steindachner from the Magdalena 

 (Fisch-f. Magdalenen Str., 1878, p. 53, pi. XIV, fig. 1) and from Guayaquil 

 (Fisch-f. Cauca and Guayaquil, pp. 36 and 50, 1880). It has been taken several 

 times since then at Guayaquil, and is recorded by Regan I. c. from the Rio 

 Condoto of the San Juan basin. 



Eigenmannia virescens was recorded by Steindaclmer (Fisch-f. Mag- 

 dalenen Str., 1878, p. 55. pi. XIV) from the Magdalena, from the Mamoni at 

 Chepo (Flussf.-Siidam. I, 1879, p. 21), from the Cauca, (Fisch-f. Cauca and 

 Guayaquil, 1880, p. 36), and Baranquilla on the ^Magdalena (Denk. Akad. Wiss. 

 Wien, LXXII, 1902, p. 147). 



Hypopomw, brevirostris was recorded by Steindachner from the Cauca 

 (Fisch-f. Cauca and Guayaquil 1880, p. 30). 



Recently a fifth species, Sternarchus rostratus, has been recorded b}' 

 Meek and Hildebrand (Field Museimi Pub., 166, 1913, p. 85) from the Tuyra 

 basin on the Pacific slope of Panama. 



During the last two yesirs large collections of Gymnotids were made by 

 Eigenmann, January to April, 1912, in the Magdalena. Cauca. Dagua. San 

 Juan and Atrato rivers; by Chas. Wilson, January to IXIarch, 1913. in upper 

 San Juan basin and in the Atrato basin; by Arthur Hemi, 1913, in the lower 

 San Juan and its tributary the Calima and in the lowlands of western Ecuador; 

 and by Henn and Wilson in the lower Patia basin. It is the purpose of the pres- 

 ent paper to report on these collections. 



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