266 ZOOGEOGRAPHY 



TABLE 5. SPECIES OF ISOPODS OCCURRING ON BOTH SIDES OF THE ISTHMUS 

 OF PANAMA 



*Aega deshaysiana (H. Milne Edwards, Paradella dianae (Menzies, 1962b) 



1840) Paraleptosphaeroma glynni Buss and 



Anopsilana browni (Van Name, 1936) Iverson, 1981 



Cleantioides planicauda (Benedict, Probopyrus pandalicola (Packard, 



1899) 1879) 



Excirolana braziliensis Richardson, *Rocinela oculata Harger, 1883 



1912 *Rocinela signata Schioedte and 



Excorallana tricornis (Hansen, 1890) Meinert, 1879 



*Nerocila acuminata Schioedte and Uromunna reynoldsi Frankenberg and 



Meinert, 1881 Menzies, 1966 



* fish parasite or fish predator 



of Cape Kennedy, which would indicate a significant cooler-water compo- 

 nent. What proportion of originally Gulf species have spread into the Carib- 

 bean, and what proportion of Caribbean and temperate east coast species 

 have entered the Gulf, cannot yet be assessed, given our incomplete knowl- 

 edge of the Gulf fauna. Because of this unresolved situation, three categories 

 of species have been separated: species ranging from north of Cape Kennedy 

 into the Caribbean — 6, 3.6% [12, 5.5%]; species occurring in the Gulf of 

 Mexico and the Caribbean — 9, 5.4% [14, 6.4%]; species occurring north of 

 Cape Kennedy, in the Gulf, and in the Caribbean— 12, 7.2% [21, 9.6%] The 

 conclusion that the fauna of the Gulf of Mexico contains an endemic compo- 

 nent, a Caribbean component, and a warm-temperate component was also 

 reached by Topp and Hoff (1972), in an analysis of the pleuronectiform 

 fishes of the Gulf 



THE BAHAMAS 



The Florida Current flowing through the Straits of Florida has been sug- 

 gested as a factor in reducing the movement of shallow-water fauna between 

 peninsular Florida and the Florida Keys on the west and the Bahamas on the 

 east (Briggs, 1974). Comparison of the number of isopod species on either 

 side of the Straits of Florida (13 from the Bahamas, 50 from southern penin- 

 sular Florida and the Florida Keys) supports this view. Of the 13 species 

 from the Bahamas, only four are "endemic," three of these being interstitial 

 microcerberideans. 



