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usual feature of the lectotype is the presence of a small rostral fen- 

 estra (pi. 8b). However, the occasional presence of such a fenestra 

 in <S. zygaena and S. blochii (in which species it is ordinarily absent) 

 suggests that the type specimen is merely a variant with regard to this 

 character. 



' g H 



Figure 22. — Distribution of pores on ventral side of head: a, Sphyrna blochii; b, S. mokarran; 

 c, S. zygaena; d, S. lewini; e, S. tiburo; f, S. media; g, S. corona; h, S. tudes. (Drawings 

 by Paul Laessle.) 



Range. — Sphyrna tudes is restricted to the western Atlantic Ocean 

 and the western Mediterranean Sea. In the western Atlantic it occurs 

 from Uruguay (Springer, 1944, p. 274) to the northern Gulf of Mexico 

 (Gilbert, 1961, p. 480). In the western Mediterranean it is recorded 

 from Nice, France (the type locality) and Livorno, Italy (Tortonese, 

 1950a, pp. 31, 32; 1950b, p. 1031). 



