ICHTHYOLOGY OF VENEZUELA — SCHULTZ 23 



During 1942 my assistant, Rafael Navarro, and I were collecting 

 fishes in a swamp north of Sinamaica, Maracaibo Basin. We had 

 walked nearly half a mile across this shallow muddy mire, pushing a 

 small boat (cayuca) in front of us. Along the way we noticed many 

 stingrays measuring up to a foot across their disks. The water was a 

 few inches to a foot deep, and our feet sank as far into the soft muddy 

 bottom. We made a fair collection of the various kinds of fishes 

 present and started back. I urged Navarro not to pick up his feet 

 in this mud but to push them forward at the surface to avoid stepping 

 on a stringray. 



Suddenly I heard him cry out in agony. A stingaree had driven its 

 spine into his anlde, but fortunately the spine did not break off. 

 When we reached shore I cleaned the wound, swabbed it out with 

 iodine, and bandaged it. At camp that night I found the wound 

 was deep, to the bone, but the flesh showed little swelling. I washed 

 it and put on a larger bandage saturated with 1:1000 metaphen. 

 After a week of this treatment the lesion was completely healed. 



Since aU stingarees hide, partly bmied in the mud or sand of the 

 bottom, they are always a potential danger to all who wade over such 

 bottoms in tropical seas or in certain tropical rivers. Since the chief 

 hazard is caused by stepping on one of these fishes it is almost com- 

 pletely eliminated by pushing one's feet along the bottom in the upper 

 layer of mud or sand. Another method of avoiding the danger would 

 be to carry a pole and probe the bottom as one walks forward. The 

 moment something touches the ray it wiggles off. 



KEY TO THE GENERA AND SPECIES OF DASYATIDAE REPORTED OR EXPECTED IN 



VENEZUELAN WATERS 



la. Outline of disk concave at each side of projecting snout, then rounded; 

 greatest width of disk a little more than length of disk from tip of snout to 

 its most posterior margin, not including pelvics; caudal fin moderately 

 narrow, with its tip bluntly rounded; caudal fiin with rays; eye and spiracle 

 not quite equal to interorbital space; distance from front of oronasal groove 

 to rear corner of nasal flap 2 in width of nasal flap; eye 2}^ in interorbital 

 space and 4K in length of snout; an irregular series of small tubercles or 

 spines along middle of back behind interorbital space and on tail; color 



plain Ught brownish gray in alcohol Urotrygon venezuelae, new species 



1&. Outline of disk, at each side of snout rounded or nearly so, not concave; greatest 



width of disk less than length of disk from snout to its posterior margin, 



pelvics not included. 



2a. Caudal fin broad, short, and bluntly rounded; greatest width of caudal fin 



nearly equal to width of nasal flap; caudal fin with rays; eye and spiracle 



much greater than interorbital space; distance from front of oronasal 



groove to outer rear corner of nasal flap about 2 times in width of nasal 



flap; eye large, equal to or greater than interorbital space and about 2 in 



the snout; no spines along middle of back and tail only small prickles; 



fourth gill slit a little closer to center of anus than to snout tip; color in 



