THE CATFISHES OF VENEZUELA — SCHULTZ 215 



PINIRAMPUS PIRINAMPU (Agassiz) 



Pimelodus pirinampu Agassiz, in Spix, Selecta genera et species pisciura . . . 



Brasiliam . . ., P- 20, pi. 8, 1829 (ref. copied). 

 Pirinampus pirinampus Eigenmann and Eigenmann, Occ. Pap. California Acad. 



Sci., vol. 1, p. 104, 1890 (Venezuela). — Ribeiro, Arch. Mus. Nac. Rio de 



Janeiro, vol. 16, No. 4, p. 304, 1911 (Venezuela). 

 ? Pimelodxis barbancho Humboldt, Recueil d'observations de zoologie . . ., vol. 



2, p. 172, 1811 (Venezuela). (Ref. copied.) 



Genus MEGALONEMA Eigenmann 



Megalonerna Eigenmann, Rep. Princeton Univ. Exped. Patagonia, vol. 3, p. 383^ 

 1910 (jiomen nudum); Mem. Carnegie Mus., vol. 5, p. 150, fig. 31, pi. 10, 

 fig. 2, 1912. (Type, Megalonema platycephalum Eigenmann.) 



Since Megalonema punctatum Meek and Hildebrand and M. rohuslum 

 Meek and Hildebrand have been referred to Pimelodus clarias punc- 

 tatus by tbese authors, there remain three other species in the genus: 

 Megalonema platycephalum Eigenmann, M. xanthum Eigenmann, and 

 M. rhabdostigma Fowler (Proc. Acad. Nat. Sci. Philadelphia, 1914, 

 p. 256, fig. 10, from Rupununi River). 



Although I have not seen the type of the last-named species, 

 Fowler's figure 10 of rhabdostigma does not appear to belong to the 

 genus Megalonema for the following reasons: (1) He says ''eyelids 

 free without adipose development," while the true members of this 

 genus have free ej'-elids and the eyes have adipose eyelids strongly 

 developed dorsally; (2) dorsal and pectorals with definite spines, but 

 in Megalonema the first ray is articulated; (3) "occipital process and 

 articulating predorsal buckler, besides exposure of shoulder-girdle 

 over pectoral origin"; in Megalonema the supraoccipital process 

 does not nearly reach the predorsal plate, there is no exposure of 

 shoulder-girdle over the pectoral base, and there is no backward 

 extension of the coracoids above or behind base of pectorals; (4) 

 Fowler says "P, I, 9," while in Megalonema the various species have 

 I, 12 to I, 14 rays in the pectoral fin; (5) the color pattern, shape, and 

 all characters described by Fowler cause me to conclude that his Meg- 

 lonema rhabdostigma should be referred to the genus Pimelodus, and 

 it no doubt will be proved to be a synonym of Pimelodus ornatus Kner. 



KEY TO THE SPECIES OF MEGALONEMA 



la. Total length of adipose fin contained about 2J4 times in standard length; first 

 ray of dorsal fin two-thirds length of adipose fin; anal rays v, 8 to 10, usually 

 9 or 10 branched rays; pectoral I, 13 or I, 14; gill rakers 4 or 5+14 or 15; 

 depth 4^ to 5; first dorsal ray reaches ){ along adipose fin; maxillary barbel 

 reaching to caudal fin base or nearly there. 



Megalonema xanthum * Eigenmann 



• This species was reported from Qirardot and Apulo, Colombia, Magdalena system, by Eigenmann; 

 Indiana Univ. Bull., vol. 10, No. 8, pp. 16-17, 1913. 



