THE SHORE FISHES OF PERU 71 



Two specimens — the type (U.S.N.M. No. 127793), a male, taken 

 with a gill net in Paita Bay, 276 mm. long, and a paratype, also a male, 

 taken with a trammel net at La Lagunilla, having a length of 252 mm. — 

 are at hand. The proportions given first in each instance apply to 

 the type. The two specimens differ in the number of spines on the 

 back and somewhat in color, as pointed out in the description. The 

 differences are believed to constitute individual variations and possibly 

 in part variations with age. A very young individual, a male 78 mm. 

 long, from Sechura Bay, which has no spines or prickles, apparently 

 also belongs here. 



This species is related to U. chilensis (Giinther), but according to the 

 description and figure the tail is proportionately longer in the latter, 

 being longer than the disk and contained 1.75 times in total length; the 

 caudal fin is less strongly pointed; and the disk is wider, its width being 

 contained 1.55 in total length; also prickles on the snout are not 

 mentioned. U. peruanus differs from all the other species of which 

 specimens are available for examination, including mundus, asterias, 

 aspidurus, and goodei, in the narrower and more sharply pointed caudal 

 fin. 



Range. — Known only from Peru from the specimens listed above. 



Genus PTEROPLATEA MuIIer and Henle, 1837 



Disk much broader than long, the anterior angle equal to or greater 

 than a right angle, the lateral angles acute ; tail much shorter than the 

 disk, slender, with or without a spine, without a fin, usually with a 

 membranous fold along median line above and below, the lower one 

 sometimes missing; skin usually entirely smooth. 



PTEROPLATEA AFUERAE, new species 

 TUYO 



Figure 16 



Pteroplatea crebr {punctata Evermann and Radcliffe, 1917, p. 16 (not of Peters), 



Lobos de Afuera, Peru. 

 Gymnura crebripunciata Fowler, 1941a, p. 228 (in part not of Peters) (references). 

 Gymnura marmorata Beebe and Tee-Van, 1941, p. 263, fig. 25 (in part not of 



Cooper) (range; field characters; references). 



Disk much broader than long, its outline opposite snout, eyes and 

 spiracles straight, slightly concave opposite gill slits, from there to 

 outer tip very slightly convex, its distal margin very broadly and 

 gently convex, its lateral angles acute; its length 1.75 in its width, 

 1.25 in total length; length anterior to axil of pectoral 2.0 in width; 

 length anterior to vent 2.1 in width; tail very short and slender, 3.5 in 

 total length, 5.0 in width, with an extremely narrow fold above and 

 none below; snout moderately pointed, with an angle of about 110°, 

 its length to eye equal to its preoral length, 4.2 in length anterior to 



