THE SHORE FISHES OF PERU 269 



PARALONCHURUS PERUANUS (Stelndachner) 



Coco; Suco 



Genyanemus peruanus Steindachner, 1875a, p. 29, Paita and Callao, Peru (orig- 

 inal description ; generic relationship discussed) . 



Polycirrhus peruanus Jordan and Eigenmann, 1889, p. 415, Callao and Paita, 

 Peru (diagnosis, based on part of Steindachner's type material). 



Polyclemus [peruanus Starks, 1906, p. 796, Callao, Peru (description). — Ever- 

 MANN and Radcliffe, 1917, p. 108, Callao, Peru (synonymy; description). — 

 Nichols and Murpht, 1922, p. 510, Callao, Peru. 



Head 3.3 to 3.6; depth 3.25 to 3.5; D. IX or X-I, 25 or 26; A. II, 8 

 or 9; P. 17 to 19; scales 61 to 64; vertebrae 27 (one specimen dissected). 



Body elongate, compressed, more or less V-shaped anteriorly in 

 cross section, the back being very thin, greatest thickness of body 

 nearly two-thirds its depth; profile nearly straight to nape, convex 

 from there to origin of dorsal; head rather low, broad; caudal peduncle 

 moderately long, slender, compressed, 3.0 to 3.4 in head; snout very 

 blunt, vertical anteriorly, scarcely projecting beyond premaxillaries, 

 3.5 to 3.9 in head; eye rather small, 5.75 to 6.4; interorbital broad, 

 convex, 2.7 to 2.9; mouth slightly oblique; lower jaw included; max- 

 illary reaching about to posterior margin of pupil, 2.8 to 3.1 in head; 

 teeth in each jaw small, pointed, in a broad band, the outer ones of 

 upper jaw slightly enlarged, band on lower jaw interrupted anteriorly 

 on median line; preopercle with a rather finely ciliate membranous 

 margin; gill rakers slender, only about half as long as pupil, 11 to 14 

 more or less developed on lower and 7 to 9 on upper limb of first arch; 

 lateral line somewhat arched anteriorly, becoming horizontal above 

 base of anal; scales strongly ctenoid, 7 oblique rows between lateral 

 line and first dorsal spine, a narrow sheath of scales, composed mostly 

 of one series of scales on base of second dorsal, no scales on rest of fin 

 (contrary to statement in original description), extending on caudal 

 nearly to tip, none on anal, but present on base of ventral and pectoral; 

 dorsal fins close together, more or less connected by a membrane in 

 the smaller specimens, the spines very slender, the third or fourth 

 longest, 1.9 to 2.5 in head; second dorsal long, of about uniform height 

 throughout, the rays notably shorter than the longest spines; upper 

 half of margin of caudal concave, the rays of the upper acute lobe 

 and the middle rays longest and of about equal length, the lower lobe 

 shorter and broadly rounded, the margin apparently tending to be- 

 come straighter with age; anal moderate, with a nearly straight margiQ, 

 the spines rather weak, the first a mere point, the second adhering 

 closely to the soft ray, 3.1 to 3.9 in head; ventral inserted immedi- 

 ately behind base of pectoral, reaching (without filament) fully half- 

 way to anal, 1.6 to 1.75 in head; pectoral moderately long, fairly 

 pointed, the fourth and fifth rays longest, reaching to or beyond tip of 

 ventral 1.2 to 1.25 in head, 4.1 to 4.3 in length. 



