﻿Eigenmann: Fishes of Panama 



19 



The Origin of the Central American Fishes. There is 

 some evidence that Central America got at least some of the 

 ancestors of its South American types by another than the 

 Panama route. 



Gymnotus and Symbranchus, abundant in South America to 

 Guiana and Colombia, are also found in Guatemala but have 

 not been found in Costa Rica or Panama. The great develop- 

 ment of Cichlids in Mexico and Central America may indicate 

 that this family got into Central America before the present 

 bridge of Panama came above the ocean. 



A comparison of the first three columns will show how very 

 few of the fishes of southern Panama extend into Costa Rica. 



