194 PROCEEDINGS OF THE NATIONAL MUSEUM vol.94 



KEY TO THE SPECIES OF RHAMDIA REPORTED FROM VENEZUELA 



la. Maxillary barbel extending past middle of adipose fin or to caudal peduncle; 

 interorbital space 2.6 to 2.7 in head; pectoral spine with teeth on posterior 

 margin and small ones anteriorly; depth 5]>i; head 3.5 to 4 in standard 

 length; anal rays vi, 9; gill rakers 5-}- 14; p3Gtoral I, 9. 



Bhamdia sebae (Cuvier and Valenciennes) 



16. Maxillary barbel not reaching past tips of pelvics; depth 6 to QYz in standard 



length; dorsal I, 6; pectoral I, 9; anal 11 to 13; distance of adipose fin from 



dorsal lYz to V/s in head. 



2a. Pectoral spine slightly serrated along both edges; head 4^^ in standard 



length; coloration uniform, dorsal blackish with a pale band across its basal 



portion Bhamdia humilis (Giinther) 



26. Pectoral spine nearly smooth behind, with hooks along anterior margin 

 decreasing in size toward base; head 4 to 4% in standard length; pre- 

 nnaxillary band of teeth slightly wider at sides, with small backward- 

 projecting angle Bhamdia guairensis Eigenmann 



Ic. Maxillary barbel extending past tips of pelvics but not past middle of adipose 

 fin; interorbital 2.8 in head; pectoral spine serrated on both margins; 

 depth 5 to 5^; head 4 to 4.5; anal about vi, 9; gill rakers about 4 + 8 from a 

 Guiana specimen Bhamdia quelen (Quoy and Gaimard) 



RHAMDIA SEBAE (Cuvier and Valenciennes) 



Pimelodus sebae Cuvier and Valenciennes, Histoire naturelle des poissons, voL 

 15, p. 169, 1840. 



The specimens from the Maracaibo Basin, here tentatively identi- 

 fied as R. sebae, may represent a distinct subspecies. This form, 

 though fully described on the following pages, was not given a new 

 name because critical comparative material is lacking at present. 



The following specimens were collected by Leonard P. Schultz dur- 

 ing 1942 in the Maracaibo Basin of Venezuela: 



U.S.N. M. No. 121190, 16 specimens, 20.5 to 201 mm. in standard length, from 

 the Rio Machango at the bridge south of Lagunillas, March 16. 



U.S.N. M. No. 121196, a specimen 209 mm. collected in Lago Maracaibo near 

 the mouth of the Rio Concho, May 2. 



U.S.N. M. No. 121193, 3 specimens, 101 to 148 mm., taken in the Rio San 

 Juan at the bridge, Motatdn system, March 20. 



U.S.N.M. No. 121192, 5 examples, 170 to 269 mm., obtained on March 11 from 

 a cafio half a mile west of Sinamaica. ' 



U.S.N.M. No. 121197, 2 specimens, 91 and 277 mm., taken March 2 in the Rfo 

 Negro below the mouth of the Rio Yasa. 



U.S.N.M. No. 121191, a specimen 264 mm., collected February 26 in the Rio 

 San Juan, about 12 km. south of Rosario, Estado de Zulia. 



U.S.N.M. No. 121199, an example, 112 mm., taken February 21, 1942, in the 

 Rfo Palmar near Totuma, about 100 km. southwest of Maracaibo. 



U.S.N.M. No. 121194, 2 specimens, 34 and 40 mm., collected March 17 in the 

 Rfo Motatdn at bridge 22 km. north of Motatdn. 



U.S.N.M. No. 121195, 4 specimens, 87 to 105 mm., taken in the Rio San 

 Pedro at bridge (Motatdn system), March 20. 



This species was taken most frequently over muddy to sandy bot- 

 toms of pools in rivers, as well as in swamps and in Lago Maracaibo. 



