THE SHORE FISHES OF PERU 

 XENICHTHYS RUPESTRIS, new species 



Figure 50 



233 



Head2.8 to 3.1; depth 3.2 to 3.5; D. XI-I, 17 or 18; A. Ill, 17 or 18; 

 P. 15 or 16; scales 65 to 70; vertebrae 26 (one specimen dissected). 



Body quite compressed, its greatest thickness about half its depth; 

 back moderately elevated; profile over snout and eyes nearly straight; 

 ventral outline anteriorly rather strongly convex; head quite com- 

 pressed; caudal peduncle short, compressed, 3.3 to 3.6 in head; snout 

 pointed, 3.6 to 4.4; eye round, its vertical and longitudinal diameters 

 being equal, 3.0 to 3.3; interorbital convex, 5.2 to 6.0; mouth quite 

 oblique; lower jaw projecting; maxillary reaching a little beyond front 

 of eye, 2.4 to 2.8 in head; teeth minute, in a narrow band on each jaw, 

 and in a V-shaped band on vomer; gill rakers small, those at angle 

 scarcely as long as pupil, 16 to 18 more or less developed on lower and 



Figure 50. — Xenichthys rupestris, new species. From the type, 90 mm. long, Lobos de 

 Afuera Bay, Peru (U.S.N.M. No. 127998). 



6 or 7 on upper limb of first arch; scales ctenoid, reduced in size along 

 the back, the reduced scales extending to lateral line anteriorly, but 

 not posteriorly, about 12 or 13 rows between lateral line and base of 

 first dorsal spine, and 10 or 11 between lateral line and base of first 

 soft ray of dorsal, scales extending more or less on all the fins exclusive 

 of the spinous dorsal, the second dorsal and anal being densely scaled; 

 dorsal fins nearly or quite separate, the spines rather weak, the fourth 

 usually longest, generally failing to reach origin of second dorsal if 

 deflexed, 1.75 to 2.1 in head, margm of fin nearly straight; caudal fin 

 (more or less damaged) apparently with a very shallow fork; anal 

 spines small, graduated, the second 5.1 to 6.0 in head, origin of fin 

 about opposite that of dorsal, the soft part similar to that of dorsal; 

 ventral inserted a little behind base of pectoral, failing to reach vent, 



