March, 1914. List of Fishes of Costa Rica — Meek. 107 



85 to 130 mm. (Alfaro); Paso Agres (i), 100 mm. (Alfaro); Turrubalcs 

 (5)^ 75 to 115 mm. (Alfaro); Rio Higueron (48), 45 to 103 mm. (Alfaro) ; 

 Las Canas, Taboga (50), 30 to 40 mm. (Alfaro). 



Astyanax regani Meek. 



Astyanax regani Meek, Pub. Field Mus., Zool. Ser., vii, igo8, 207 

 (Las Caiias, Costa Rica, Pacific Slope). 



This species is nearest to A. albeolus. It differs in being more 

 slender and more robust anteriorly. The snout is blunter and more 

 decurvcd, the iins slightly shorter. In this species the anterior dorsal 

 rays are shorter than the head, in A. albeolus they are as long as, or 

 e\'en longer than, the head. A. regani also has a shorter anal base. 



Las Canas, Costa Rica (type), 135 mm. (Alfaro); Pacific Side, 

 Costa Rica (i), 100 mm. (Alfaro); Turrucarcs (3), 95 to no mm. 

 (Alfaro). 



Bryconamericus scleroparius (Regan). 



Tetragonopterus scleroparius Regan, Ann. & Mag. Nat. Hist., 1908, 

 455 (Rio Iroquois). 



Bryconamericus peruanus ricce Eigenmann, Bull. Mus. Comp. Zool., 

 1908, 106 (Chitaria, Costa Rica). 



Astyanax rohustus Meek, Pub. Field Mus., Zool. Ser., x, 191 2, 69 

 (Virginia River, Costa Rica). 



This species varies considerably. The young, usually the smaller 

 specimens up to 70 mm., have a higher and more pointed dorsal, the 

 free edge of the fin being straight or slightly convex. The caudal lobes 

 are pointed, and the color silvery {B. scleroparius (Regan) and B. p. 

 riccB Eigenmann). The larger specimens (140 mm.) have a much more 

 robust body, the caudal peduncle being very broad; the dorsal fin is 

 shorter, and the free edge convex. The caudal lobes are very short 

 and rounded. The color of the large specimens is very dark, with a 

 reddish tinge in life {Astyanax rohustus Meek). The faint humeral 

 spot on the young apparently disappears with age. Caudal spot 

 scarcely defined in the large specimens, but present in the smaller ones, 

 extending on the rays to the end of the caudal fin. Inner premaxillary 

 teeth 4-4, the outer 5-5. 



La Junta (5), 76 to 100 mm.; Virginia (50), 75 to 143 mm.; Parismina 

 (30), 80 to 130 mm.; Zent, April 12 (8), 85 to 115 mm.; La Victoria (6) 

 95 to 120 mm.; Guapilis (27), 85 to 122 mm.; Chitaria (3), 82 to 95 mm. 

 (Alfaro). 



