Fishes of the Western North Atlantic 



S7 



Distinctive Characters and Description. The subspecies desotoi Is distinguishable 

 from typical oxyrhynchus of comparable size by the following differences, the most 

 striking and characteristic difference being the length of the spleen. Head, pectoral, 

 and spleen given in per cent of fork length. For other details, see Vladykov {81). 



Character desotoi oxyrhynchus 



Scutes — dorsal row . . . squarish, with length much oval, with length greater than 



shorter than width; carina width;* carina (keel) low, 



(keel) typically with two without a pronounced hook 

 strong hooks 



Head 30-9-33-6''/o 26.5-27.6«/o 



Pectoral fins 1 5.5-1 6.3 "/o 1 1.5-15.1 "/o 



Spleen length le-igo/o 3-9% 



* Specimens from eastern Florida and Quebec. f Two specimens. 



Habits. The subspecies desotoi is anadromous, as is the northern subspecies oxy- 

 rhynchus. Further than this there is no detailed information on its habits, except that 

 Louisiana fishermen occasionally capture large Sturgeon around the mouth of the Mis- 

 sissippi River and in the Sound, where they have been reported as "Common Stur- 

 geon" (5^: 41 1-412). Adults probably visit several rivers on the northern and eastern 

 shore of the Gulf of Mexico for spawning purposes. 



Range. Apparently its occurrence is limited to the Gulf of Mexico, the northern 

 coast of South America, and Bermuda (p. 54). 



Synonyms and References: 



Acifenser oxyrhynchus de sotoi Vladykov, J. Fish. Res. Bd. Canada, 12 (5), 1955: 2 (orig. descr.). 

 Acifenser oxyrhynchus Gowanloch, Bull. La. Conserv. Dep., 1933: 411 (mouth of Mississippi R.). 

 Acipenser sturio Rivas, Bull. U.S. Fish Wildl. Serv., ^^ (89), 1954: 504 ("• and e. shore. Gulf of Mexico). 

 Acipenser {oxyrhynchus) de sotoi Springer and BuUis, Spec. Sci. Rep., U.S. Bur. Comm. Fish., J96, 1956: 46 

 (Mississippi Sd.). 



Relationship of A. oxyrhynchus to A. sturio 



Some authors (see Synonyms and References, p. 56), following Ryder {6^: 234— 

 238), have considered the Atlantic Sturgeon of America to be the same species as 

 the Common Sturgeon of Europe, 



A. sturio Linnaeus; the two species Table V. Comparative Counts of A. sturio and 

 resemble each other very closely A. oxyrhynchus. 



in certain features, as is shown in Species A. sturio A. oxyrhynchus 



Table v. Authority Berg Vladykov and Beauheu 



D'Ancona, in a summary of . (-^^ ■ 93-95) (*J = 44-57) 



, , r ^ ■ Dorsal shields .. . <5-i^ 7-i3 



the characters of A. sturto, presum- Lateral shields . . 24-35 H-3S 



ably from the Mediterranean Sea, Gill rakers 18-25 17-27 



