Free-Living Copepoda 



From Ifaluk Atoll in the Caroline Islands 



With Notes on Related Species 



Introduction 



A SMALL COLLECTION of nonparasitic Copepoda — collected during a 

 survey of the fauna of Ifaluk Atoll, Caroline Islands, and obtained 

 as a result of the Coral Atoll Project of the Pacific Science Boai"d — • 

 was placed at my disposal at the end of 1959. This collection, con- 

 taining Calanoida, Cyclopoida, and Harpacticoida — some 250 indi- 

 viduals in all — proved to contain a fair number of sand-dwelling 

 species. Largely as a result of our very scanty knowledge of Pacific 

 Harpacticoida in general and sand-dweUing forms in particular, the 

 study of this highly interesting collection took much more time than 

 I originally expected, but I thought it worthwhile to report the collec- 

 tion as completely as possible and particularly to illustrate the new 

 forms as well as I could. Though the total number of species present 

 is not very impressive, the percentage of new forms among them is 

 high. Many of the previously described forms, moreover, are here 

 recorded for the first time from the Pacific area. 



For the taxonomy of the Harpacticoida, which comprises the bulk of 

 the present material, I have proceeded completely on the basis of 

 Lang's monograph (1948). One cannot avoid the fact that, in the 

 coiKse of the revision of certain families and genera, differences of 

 opinion arise: in several instances I have been forced to express view- 

 points very much at variance with those published by Lang. This 

 does not alter the permanent value of his monumental work, which 

 has greatly facilitated the identification of harpacticoids and which 

 presents a wealth of additional information. For the synonymy of 

 the species discussed here I refer to Lang's monograph; only those 

 papers that are not included in his bibliography or that have appeared 

 since have been cited in the present work. The list of references at 

 the end of this report makes no claim to completeness; only those 

 studies that have been cited are included. 



In the nomenclature of structural particulars of Harpacticoida I 

 have followed the terminology adopted by Lang; I have abandoned 

 abbreviations as much as possible and composed the descriptions in 



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