SYSTEMATICS AND DISTRIBUTION OF AN ESTUARINE ISOPOD CRUSTACEAN, CYATHURA POLITA (STIMPSON, 1855), NEW COMB., FROM THE GULF AND ATLANTIC SEABOARD OF THE UNITED STATES

¹ Department of Zoology University of California, Davis, California
² Department of Biology, Emory University, Georgia

A new combination, Cyathura polita (Stimpson, 1855), is established for a burrowing anthurid isopod widely distributed along the eastern and southern seaboard of the United States. Although it has long been considered conspecific with C. carinata (Kr\g=fscr\yer), a predominantly European species, morphological comparisons together with zoögeographical considerations, show the American forms are a distinct species first described by Stimpson as Anthura polita. Its known geographical range extends from Louisiana to Maine, with populations found in estuaries, tidal marshes, intertidal areas, etc., where salt and fresh water mix. It apparently requires a relatively stabilized sandy substrate with the stabilizing factor varying with the latitude.