Fishes of the Western North Atlantic 231 



Characters. Body slender, rather strongly compressed, its depth about equal to 

 postorbital part of head. Head long and low. Eye entirely in anterior half of head. 

 Maxillary rounded posteriorly, not quite reaching joint of mandible. Teeth all small. 

 Gill rakers slender, those at angle of first arch about as long as eye, about 33 on lower 

 limb. Dorsal fin far back, its origin about twice the distance from tip of snout as from 

 caudal base. Anal fin beginning well in advance of origin of dorsal, about 25 rays. 

 Pelvic inserted about equidistant between base of pectoral and anal origin. 



Remarks. The numerous long gill rakers and the posterior position of the dorsal 

 fin are the chief distinguishing characters of this genus. Hildebrandichthys resembles 

 Anchovia in the numerous long, slender gill rakers, but it differs in the very rear- 

 ward position of the dorsal fin. In the position of the dorsal it tends to agree more 

 or less with Pterengraulis, with which it differs in the numerous, long slender gill 

 rakers. 



This genus is founded on one species, which in turn is based on only a single 

 small (juvenile) specimen. Though it is quite distinctive, it offers some difficulties be- 

 cause the adult generic characters apparently are not fully developed. The maxillary, for 

 example, is short and rounded, which, so far as known, is true of all young Engraulidae; 

 it may or may not become produced and pointed in the adult, as shown in other generic 

 descriptions. 



Range. Known only from the Maracaibo Basin, Venezuela. 



Hildebrandichthys setiger Schultz 1949 

 Figure ^-^ 



Study Material. A single small specimen, about 37 mm TL (caudal damaged), 

 3 1 mm SL, from the mouth of Rio Cafio de Sagua, Lake Maracaibo, Venezuela. This 

 specimen retains some of the juvenile color markings, and the maxillary may not have 

 acquired its adult length and shape. 



Distinctive Characters. The numerous gill rakers, which may increase in number 

 with age, in general agree with the rakers in Anchovia clupeoides\ the posterior position 

 of the dorsal fin calls to mind Pterengraulis atherinoides. See also Remarks under genus. 



Description. Proportional dimensions in per cent of standard length, and counts, 

 based on young specimen, 3 1 mm SL. 



Body: depth 19.2. Anal fin: length of base 22.6. 



Head: length 32. Pectoral fin: length 12. 



Snout: length 5.1. 



Eye: diameter 8.7. Scales: mostly lost, ca. 38 pockets. 



Postorbital: distance 17. Gill rakers: f<2. 23+33. 



Maxillary: length 17. Fin rays: dorsal 12; anal 25; pectoral 13. 



Mandible: length 16. 



