308 PROCEEiDINGS OF THE XATIONAL MUSEUM vol.04 



2a. Evertible spines on adults on interopercle about >3 length of head; depth 

 4^^, head 2^4 in standard length; eye 9, interorbital space 2, and snout 

 1% in head; least depth of caudal peduncle 3 to 3>4 in its length; plates 

 not carinate anteriorly Panaque gibbosus (Stcindachner) ^° 



2b. Evertible spines on interopercle ]i to % length of head in adults; depth 

 3^ to 4, head 2% to 2>^ in standard length; eye IOJ3 to 12, interorbital 

 1% to l?io, and snout 1% to \% in length of head; least depth of caudal 

 peduncle 2}'2 to 2*i in its length; base of dorsal fin a little longer than 

 length of caudal peduncle; i)latcs strongly carinato on body. 



Panaque suttoni, new species 



PANAQUE NIGROLINEATUS (Peters) 



Panaque 



Chaetostomus nigrolineatus Peters, Monatsb. Akad. Wiss. Berlin, 1877, p. 471 

 (Calabozo, Venezuela). — Steikdachner, Denkschr. Akad. Wiss. Wien, 

 vol. 44, p. 7, 1882 (Orinoco River, at Ciudad Bolivar). — Rohl, Fauna 

 descriptiva de Venezuela, p. 377, fig. 188, 1942 (Orinoco). 



PANAQUE SUTTONI, new species 



Panaque 

 Pl,.\TE 10, B 



Holotype.—V.S.N.M. No. 121033, a specimen 280 mm. in standard 

 length, taken by Leonard P. Schiiltz on March 2, 1942, in the Eio 

 Negro below the mouth of the Rio Yasa, Maracaibo Basin. 



Paratypes (all collected by L. P. Schiiitz).— U.S.N.M. No. 121075, 

 1 specimen, 53 mm. in standard length, taken along with the holotype 

 and bearing the same data; U.S.N.M. No. 121035, 3 specimens, 197, 

 265, and 31 mm. in standard length, from the Rio Motatan, at the 

 bridge 22 km. north of Motatan, Maracaibo Basin, IVIarch 17, 1942; 

 U.S.N.M. No. 121034, a specimen 224 mm., same data. 



Description. — Based on the holotype and three paratypes. All 

 measurements are expressed in hundredths of the standard length, 

 those for the holotype first, followed by those for the paratypes in 

 parentheses (the Rio Negro specimens are given first), respectively. 

 Standard length (in mm.) 280 (224; 197; 265); total length (m mm.) 

 373 (— ; 275; 350). 



Length of head from tip of snout to rear edge of temporal plate 

 41.0 (42.0; 42.2; 40.0); length of head from tip of snout to posterior 

 edge of supraoccipital plate 41.4 (42.8; 42.6; 40.4); tip of snout to 

 upper edge of gill openkig 24.6 (28.6; 26.4; 26.4); width of head at 



'0 Chaeloflomus coMiodon (sive gibbosus) Steindachner, Sitzb. Akad. Wiss. Wien, vol. 80, p. (69), 185, 1879 

 (Rfo Cauca). Not from Maracaibo Basin, but closely related to the form collected in that basin and 

 described as new. 



