Miratidotea 259 



Idotea Fabricius, 1798 



DIAGNOSIS Antennal flagellum multiarticulate. Maxillipedal palp of four or 

 five articles. Uropod uniramous. Pleon consisting of two complete and one 

 incomplete pleonites plus pleotelson. 



Key to species of Idotea 



1 . Posterior margin of pleotelson truncate metallica 



Posterior margin of pleotelson with distinct median lobe balthica 



Idotea balthica (Pallas, 1772) 

 Figure 108E 



DIAGNOSIS 6 24.5 mm, ovigerous 9 13.2-23.5 mm. Anterior margin of 

 cephalon concave. Cephalon dorsally smooth. Pereonites evenly convex, 

 smooth. Posterior margin of pleotelson with rounded median lobe. 



RECORDS Worldwide in tropical to cold-temperate waters, often on floating 

 seaweed, from surface to 357 m. 



Idotea metallica Bosc, 1802 

 Figure 108F 



DIAGNOSIS 6 30.0 mm, ovigerous $ 22.2 mm. Cephalon with sinuous fur- 

 row in posterior half Pereonites 2-4 laterally with rounded convex area close 

 to coxae. Posterior margin of pleotelson truncate. 



RECORDS Worldwide in tropical to cold-temperate waters, often on floating 

 seaweed, from surface to 200 m. 



Miratidotea Kensley, 1987a 



DIAGNOSIS Antennal flagellum of single clavate article. Maxillipedal palp 

 of four articles. Uropod uniramous. Pleon consisting of two complete and two 

 incomplete pleonites plus pleotelson. 



