HAMMERHEAD SHARKS GILBERT 



37 



knows of no authentic record for this species from the Gulf of Mexico 

 or Caribbean, all literature records applying to Sphyrna lewini, which 

 is common there. 



In the eastern Atlantic Sphyrna zygaena is known from Scotland 

 south to Senegal, in northwest Africa (Cadenat, 1951, p. 46), and also 

 from the Mediterranean Sea. Records of S. zygaena farther south 

 along the coast of Africa (Irvine, 1947, pp. 89, 90) and from South 

 Africa (Smith 1953, pp. 46, 47) may not have been based on this 

 species, however, since in neither case were adequate descriptions 

 given, and the hammerheads pictured represent species other than 

 zygaena. Considering that the cool waters off South Africa are suit- 

 able for S. zygaena, however, it is likely that the species does occur 

 there. 



I 



ffiTF ^Htaffi ^SfeaSy ^^ 



Map 2. — Distribution of Sphyrna zygaena. 

 (Solid = specimens examined; hollow = confirmed literature references.) 



In the eastern Pacific Sphyrna zygaena is known from western South 

 America (Chile, Peru, and the Galapagos Islands) and (one record) 

 Panama, and from southern Cahfornia and Mexico (south to the 

 Gulf of Cahfornia), but mtensive collecting has failed to reveal its 

 presence between the above two areas. In the northwestern Pacific 

 S. zygaena is common around southern Japan, although the exact 

 northern Umits of its range there are uncertain. It seems to be absent 

 from the Hawaiian Islands and the East Indian area, but is present 

 off New Zealand and southern Australia. It probably is also present 

 in the southern parts of the Indian Ocean as well. 



Sphyrna {Sphyrna) lewini (Griffith and Smith) 



Figures 10, 21d, 22d; Plates 3, 6b, 9b, 10b 

 1 Cestrorhinus caroliniensis Blainville, 1816, p. 121. (Name only.) 

 ICestrorhinus pictus Blainville, 1816, p. 121. (Name only.) 



Zygaena malleus Valenciennes, 1822, p. 223. (In part; description; illustration of 

 head; Mediterranean Sea and Atlantic Ocean; teeth described as denticulate.) 

 "^Zygaena indica Van Hasselt, 1823, p. 315. (Type locality: Java.) 

 Zygaena lewini Griffith and Smith, in Cuvier, Griffith, and Smith, Animal King- 

 dom, vol. 10, p. 640, pi. 50, 1834. (Original description; figure; no type 

 specimen; type locality, south coast of New Holland.) 

 Sphyrnias zygaena (misidentification in part) Gray, 1851, p. 48. (In part; 

 malleus included in synonymy.) 



