WESTERN ATLANTIC SHRIMPS OF THE GENUS PENAEUS 



BY ISABEL PEREZ FARFANTE, SYSTEMATIC ZOOLOGIST ' 



BUREAU OF COMMERCIAL FISHERIES SYSTEMATICS LABORATORY 

 WASHINGTON, D.C. 20560 



ABSTRACT 



Four subgenera of the genus Penaeus are described 

 (Litopenaeus , Penaeus s.s., Fenneropenaeus , and 

 Melicertus). Eight species and subspecies (P. setiferus, 

 P. schmitti, P. duorarutn duorarum, P. duorarum 

 notialis, P. aztecus aztecus, P. aztecus subtilis, P. pau- 

 lensis, and P. brasiliensis) are recognized as occurring 

 in the western Atlantic. Synonymies are given. Lec- 

 totypes have been designated for two species, and 

 the disposition of all types is shown. Diagnoses, de- 

 tailed descriptions, and illustrations are presented for 

 each species and subspecies. Geographic and bathy- 



metric distributions are given. Affinities are discussed, 

 and conclusions concerning ranges of variation and 

 their spatial distribution are based on morphometric 

 studies and other characters. The development of the 

 external genitalia through the juvenile stage and the 

 size range at which each taxon reaches the subadult 

 stage are presented. Many details of ecology and life 

 history are critically summarized and reviewed. A 

 brief appraisal of the commercial importance of each 

 form is also given. 



The economic importance of tlie shrimp industry 

 in eastern America becomes abundantly clear when 

 one realizes that in 1965 the United States pro- 

 duced over 100 million kg. of Penaeus shrimp, and 

 Latin America together with the Guianas har- 

 vested no less than 57 million kg. The fact that 

 these animals are of such value has luidoubtedly 

 been largely responsible for the extensive research 

 that has been devoted to the many aspects of the 

 biology of the members of the genus Pendens. 

 Even so, there has been a long-felt need for a 

 comprehensive treatment of the systematics of the 

 group. This need has been emphasized by the 

 fact that, although much valuable infonnation 

 exists for the group as a whole, misidentifications 

 of individuals and of populations have led to 

 confusing and sometimes conflicting conclusions. 



The extensive collections of Penaeus available 

 for this study have enabled me to evaluate the in- 

 terrelationships of the western Atlantic members 

 of the genus and, in turn, their aifinities with those 

 occurring elsewhere. To express the supraspecific 

 relationships that have been recognized, I propose 



' Also Associate in Invertebrate Zoology, Museum of Comparative Zoology, 

 Harvard University, Cambridge, Mass. 02138. 



Published June 1969. 



FISHERY BULLETIN : VOL. 67, NO. 3 



four subgenera and provide a key to facilitate 

 their recognition. This key, as well as that which 

 follows, is arranged solely for convenience and no 

 phylogenetic inferences should be drawn from it. 



Because species descriptions are widely scattered 

 in literature that is not readily available and be- 

 cause most of these descriptions do not take into 

 account many of the characters that have been 

 found to be of considerable taxonomic importance, 

 each taxon occurring in eastern American waters 

 has been redescribed and figured. 



As nearly as possible, a complete synonymy and 

 list of references (including misidentifications) 

 are indicated for each species and subspecies, and 

 the page citations are included. All references 

 listed were consulted in the original. Eveiy at- 

 tempt has been made to correlate earlier findings 

 with the taxa recognized here, but, as might be 

 expected, I was not always successful. In listing 

 the types and their dispositions, some modifica- 

 tions of the original designations have been made. 

 A list of the material examined precedes a brief di- 

 agnosis and a detailed description of morphologi- 

 cal characters. 



In addition, for each species and subspecies, the 

 range of variation of these characters is included 



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