60 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 9e 



STEBNOPYGUS PEJERATON. new species 



Peje rat6n 

 Plaie 1, A 



Holotype.— U.S.N. M. No. 121572, 505 mm. in total length, collected 

 by Leonard P. Schiiltz in the Rio Ap6n, about 35 km. south of Rosario, 

 in the Maracaibo Basin, February 26, 1942, 



Paratypes. — The paratypes were collected by Leonard P. Schultz 

 during 1942 in the Maracaibo Basin of Venezuela (measurements 

 are for total length): 



U.S.N.M. No. 121564, 17 specimens, 121 to 645 mm., taken with the holotype 

 and bearing same data. 



U.S.N.M. No. 121570, 14 specimens, 143 to 385 mm., Rfo Palmar at bridge, 

 70 km. southwest of Maracaibo, March 6. 



U.S.N.M. No. 121568, 3 specimens, 165 to 188 mm., Rfo Machango, 20 km. 

 above bridge, south of Lagunillas, March 21. 



U.S.N.M. No. 121569, 2 specimens, 195 and 228 mm., Rfo Pahnar near Totuma, 

 about 100 km. southwest of Maracaibo, February 21. 



U.S.N.M. No. 121565, 14 specimens, 117 to 442 mm. Rfo Motatdn at bridge 22 

 km. north of Motat^n, March 17. 



U.S.N.M. No. 121566, 7 specimens, 131 to 615 mm., Rfo Negro below mouth 

 of Rfo Yasa, March 2. 



U.S.N.M. No. 121567, 17 specimens, 163 to 430 mm., Rfo Socuy, 3 km. above 

 mouth, February 24. 



U.S.N.M. No. 121571, 2 specimens, 635 and 710 mm., Rfo Machango at bridge 

 south of Lagunillas, March 16. 



Description. — Based on the holotype and paratypes. Measure- 

 ments, expressed in hundredths of the distance from snout to rear end 

 of anal fin, first for the holotype, then for a paratype, in paren- 

 theses, are recorded below, respectively. Total length in mm. 505 

 (187). 



Distance from tip of snout to rear end of anal fin in mm. 455 (160). 

 Length of anal fin base 81.7 (86.3); length of head 16.5 (16.9); snout 

 5.28 (5.75); eye 0.92 (1.06); interorbital space 2.75 (3.81); postorbital 

 length of head 10.0 (10.6); distance from snout to anus 10.3 (11.9); 

 snout to anal origin 16.8 (18.1); snout to occiput 12.9 (13.5); snout to 

 pectoral insertion 16.1 (10.9); length of longest pectoral ray 6.26 

 (6.88); longest anal ray 5.72 (6.56); greatest depth of body 13.1 (12.8); 

 depth of head through eyes 5.82 (5.94) ; distance from anterior nostril 

 to posterior nostril 1.87 (1.88); eye to posterior nostril 2,53 (2.56); 

 width of gill opening 4.28 (5.38); tip of snout to rictus 3.41 (3.12); 

 tip of snout to rear of maxillary 3.96 (3.44) ; length of tail beyond end 

 of anal fin 11.2 (16.4). 



The following counts were made, respectively: Anal rays 298 (282); 

 pectoral rays iii,13-iii,14 (iii,13-iii,13). There appear to be about 

 20 to 25 scales between the lateral line and midline of the back. 



