A SYSTEMATIC CATALOGUE OF THE FRESH WATER 

 FISHES OF PANAMA. 



All of the fishes of the fresh waters of Panama belong to the class 

 Pisces (fishes) and to the subclass Teleostomi (the true fishes), which 

 possess a bony skeleton; a well developed skull; gill-opening a single 

 slit on each side; nostrils at least two, not median; fins well developed, 

 usually paired; alimentary canal more or less convoluted. 



KEY TO THE FAMILIES OF FRESH WATER FISHES OF PANAMA. 



a. Scales wanting, body smooth or with bony plates; one to 6 pairs 

 of barbels or whiskers more or less developed about the mouth 

 and nostrils. 



b. Body wholly naked (naked in Panama species) or with a single 

 series of bony plates along side. 



c. Adipose fin present. 



d. Mouth terminal or subterminal; the lips not reverted and not 

 forming a disc. Silurida, p. 239. 



dd. Mouth inferior; the lips reverted, forming an oval sucking disc. 



Cydopidce, p. 265. 



cc. Adipose fin wanting. Pygidiidce, p. 266. 



bb. Body mostly or wholly covered with bony plates. 



e. Sides and back and often the ventral surface covered with bony 

 plates; mouth wholly inferior; the lips reverted, forming a 

 sucking disc. Loricarnda, p. 246. 



ee. Sides with 2 series of bony plates; mouth terminal or subterminal; 



the lips not reverted nor developed into a sucking disc. 



CallichihyidcB, p. 263. 

 aa. Scales usually present (present in all of the Panama species) ; no 



whiskers about the mouth and nostrils. 



f . Fins without spines. 



g. Body compressed or subterete, not eel-shaped; dorsal fin present, 

 h. Adipose fin usually present (wanting in Phanagoniates and 



Hoplias); head naked, usually more or less compressed; lateral 



line complete or not (wanting in Piabucind). Characid<B,p. 267. 

 hh. Adipose fin wanting; head partly scaly, usually depressed, flat 



above; lateral line wanting. Pceciliida, p. 313. 



gg. Body more or less eel-shaped; dorsal fin wanting or represented 



by a mere filament. Gymnotida, p. 306. 



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