CHARACID FISHES — ^WEITZMAN 



39 



Description. — Body elongate, slender, sides only slightly flattened 

 anteriorly and caudal peduncle compressed. Greatest depth lying 

 just anterior to anterior base of dorsal and anal fins. Standard 

 length of largest specimen 44.5 mm. One old aquarium specimen 

 reached a standard length of 44.0 mm. after living 2^ years. Greatest 

 body depth 5.4 (4.9-5.7) ; least depth of caudal peduncle 10.9 (10.4- 

 12.1); length of caudal peduncle (including both sexes) 5.7 (5.3-6.1); 

 snout tip to origin of dorsal fin about 1.9 in all adult specimens; snout 

 tip to origin of anal fin about 1.3 in all adult specimens. 



Head elongate and somewhat depressed. Top of head very slightly 

 convex between eyes. Snout rounded in horizontal and vertical 

 profiles. Head 4.0 (3.8-4.1); eye in head 3.2 (3.0-3.2); snout m eye 

 0.9 (0.8-1.0) ; least width of bony interorbital in greatest eye diameter 

 1.1 (1.0-1.2). 



Figure 9. — Poecilobrycon harrisoni male, SL 38.5 mm., SU 50243. 



Premaxillary with 7 quadri- to septemcuspid teeth. Most with 5 

 or 6 cusps; cusps subequal or posterolateral cusps most prominent. 

 MaxUlary with 1 conical, bicuspid, or tricuspid tooth. Dentary with 

 7 to 8 (usually 8) teeth in first row. Posterior 2 teeth with 3 to 5 

 subequal cusps, remainder of teeth in first row with 6 subequal cusps. 

 Second dentary tooth row of about 12 to 15 small conical teeth. Gill 

 rakers 7 + 13 in alizarin preparations. 



Dorsal fin rays ii,8; anal iii,9; pectoral i,10 to i,ll; pelvic fin rays 

 ii,7. Adipose fin varying from well developed to rudimentary or 

 absent. Caudal fin with principal rays 10/9; distal tips of all ray 

 elements of first 10 principal rays included in upper lobe. Lower 

 caudal lobe with all elements of remaming 9 principal rays. 



Radial grooves of scales in median series below dorsal fin shown in 

 figure 9. Posterior field with 1 to 4, dorsal and ventral fields 1, and 

 anterior field 2 to 5 or 6 radial grooves. Scales in a lateral series 27 



