322 BULLETIN 189, UNITED STATES NATIONAL MUSEUM 



the first of this species to be reported from Peru, were collected by 

 the Mission in Lobos de Tierra Bay, and in Chimbote Bay. They 

 seem to agree perfectly with specimens of similar size from Panama 

 Bay. 



Range. — Gulf of California to northern Peru. Previously recorded 

 from only as far south as Panama Bay. 



Family OPLEGNATHIDAE 



Body short and deep, rather strongly compressed; mouth small; 

 teeth fused, forming a continuous plate (beak) in each jaw, each plate 

 with a median suture; premaxillaries not protractile; maxillary not 

 concealed under preorbital; nostrils paired; gills 4, a slit behind the 

 fourth; gill membranes broadly united, free from the isthmus; gill 

 rakers short, about 12 on lower limb of first arch; lateral line single, 

 complete; scales small, ctenoid, extending at least on bases of the 

 vertical fins; dorsal fin continuous, composed of about 10 to 13 spines 

 and 11 to 20 soft rays; anal with 3 spines, soft part like that of dorsal, 

 though frequently shorter; ventrals thoracic, with 1 spine and 5 soft 

 rays. 



A single genus, known from South Africa, Australia, Japan, and 

 Peru, is recognized. 



Genus OPLEGNATHUS Richardson, 1840 



The characters of the genus are those of the family. It has no near 

 relatives. A single species is known from American waters. 



OPLEGNATHUS INSIGNIS (Kner) 



LoRO; LoRiTo; Perico 



Scarostoma insigne Kner, 1867, p. 715, pi. 2, west coast of South America (original 



description). 

 Hoplognathvs insignis Regan, 1913, p. 279, Lobos de Tierra, Peru. 

 Oplegnaihvs insignis Evermann and Radcliffe, 1917, p. 109, Lobos de Afuera 



and Paita, Peru (synonymy; description; compared with 0. fasciatus). — 



Nichols and Murphy, 1922, p. 510, North, South, and Central Chincha 



Islands (size attained; habitat). 



Head 2.8 to 3. 1 ; depth 1.6 to 2. 1;D. XI, 17; A. Ill, 12 to 13; P. 16 

 or 17; scales too small and irregular to enumerate accurately, about 

 115 to 130. 



Body short and deep, strongly compressed, its greatest thickness 

 about 3.0 to 3.5 in its depth; caudal peduncle short and deep, 2.1 to 2.5 

 in head; snout pointed, 2.2 to 2.6 (4.2 in a juvenile) in head; eye 4.8 

 to 6.1 (3.33 in a juvenile); interorbital 3.1 to 3.6 (4.2 in a juvenile); 

 mouth rather small ; maxillary reaching nearly or quite to front of eye, 

 2.6 to 3.2 in head (3.6 in a juvenile) ; teeth fused, forming a continuous 

 plate (beak) , with a median suture ; margin of preopercle finely serrate ; 



