3 go Memoir Sears Foundation for Marine Research 



in recent surveys of Sting Rays of the western Pacific-Indian Ocean region and Red 

 Sea,i" i5ut we think it is likely that final revision will result in a drastic reduction in this 

 number. One species, H. pacifica (Beebe and Tee- Van) 1 94 1 , is known from Costa 

 Rica on the Pacific Coast of Central America and another, H. schmardae (Werner) 

 1904, from the western tropical Atlantic. The genus seems not to have been encount- 

 ered in the eastern side of the Atlantic as yet, but it is to be expected along tropical West 

 Africa. The one Atlantic species is included in the Key, p. 343. 



Himantura schmardae (Werner) 1904 

 Figures 93, 94 



Study Material. Three immature males, 242-563 mm broad, from Largorema 

 Island and Toro Point, Atlantic Panama, and from the West Indies, in the U. S. 

 National Museum. Also six specimens, male and female, 244-405 mm wide, from near 

 Havana, Cuba, and Carmen, Mexico (Gulf of Campeche), in the Harvard Museum 

 of Comparative Zoology. 



Distinctive Characters. The ovate shape of its disc, evenly arcuate in front as well 

 as broadly rounded outwardly, combined with the fact that the upper surface of the 

 disc as well as of the anterior part of its tail is closely and evenly set with small blunt 

 tubercles, with one larger tubercle on each shoulder, make this perhaps the easiest to 

 identify among the long-tailed Sting Rays of the western Atlantic. It is also unique 

 among western Atlantic species in the dichotomously quadriradiate structure of the 

 small tubercles and in the position of the tail spine (or spines) far rearward. 



Description. Proportional dimensions in per cent of extreme breadth of disc. Male, 

 242 mm wide, from Largorema Island, Atlantic Panama (U. S. Nat. Mus., No. 

 128388). Male, 563 mm wide, from Toro Point, Canal Zone (U. S. Nat. Mus., No. 

 86071). 



Disc: length 97.3, 89.5. 



Snout length: in front of orbits 20.7, 19.0; in front of mouth 20.3, 17.0. 



Orbits: horizontal diameter 5.2, 3.3; distance between 11.2, 12.0. 



Spiracles: length 9.1, 6.4; distance between 17.4, 14.6. 



Mouth: breadth 9.1, 7.5. 



Exposed nostrils: distance between inner ends 8.3, 8.3. 



Gill openings: lengths, ist 4.1, 3.2; 3rd 3.7, 3.4; 5th 2.5, 3.1 ; distance between 

 inner ends, ist 23.2, 20.5; 5th 18.6, 15.0. 



Pelvics: anterior margin 20.7, 19.0. 



Distance: from tip of snout to center of cloaca 86.1, 80.0; from center of cloaca 

 to origin of caudal spine 80.3, 78.2. 



Disc only a little broader than long (about i.o-i.i times), ovoid; snout marked 

 only by a low papilla; median sector of anterior contour broadly arcuate, becoming 



155. Whitley, Fish. Aust., i, 1940: 211; Fowler, Bull. U.S. nat. Mus., 100 (jj), 1941: 405. 



