THE ZOOGEOGRAPHICAL DISTRIBUTION OF THE INDO- 

 PACIFIC LITTORAL HOLOTHURIOIDEA 



By Jose S. Domantay 



Biological Research Laboratory 



Bureau of Fisheries 



Manila, Philippines 



Introduction 



Ekman in his Zoogeography of the Sea (1953) used "shelf fauna" 

 for "littoral" in its widest sense. The terms "shore fauna" and "coastal 

 fauna" according to Ekman are frequently used by both English and 

 American authors, but are not fully adequate to convey the lower limits 

 of the fauna in question. The littoral holothurioidea referred to in 

 this paper do not cover the entire shelf holothurian fauna of a sea-floor 

 to a depth of about 200 meters. The present study of the littoral forms 

 of Holothurioidea is confined only to the species recorded from a depth 

 not exceeding 50 fathoms, approximately half of the depth of Ekman's 

 shelf fauna. 



The Zoogeographical Division of the Indo-Pacific Ocean 



Ekman divided the warm-water fauna of the shelf into two main 

 regions: the Indo-West-Pacific and the Atlanto East-Pacific-areas. Each 

 of the two main regions is subdivided into sub-regions. Although it is 

 possible to distinguish several sub-regions, the present incomplete know- 

 ledge of faunistic facts does not allow as yet any precise delimitation 

 of the various sub-regions. For this reason, we may subdivide the entire 

 Indo-Pacific region into ten distinct provinces, namely; the North Pa- 

 cific, South Pacific, East Pacific, West Pacific, Northwest Pacific, South- 

 west Pacific, Northeast Pacific, Southeast Pacific, Central Pacific and 

 the Indian Ocean. The Indo-West-Pacific of Ekman comprises the In- 

 dian Ocean, West Pacific (warm waters). Northwest Pacific (warm and 

 cold waters). Central Pacific (warm waters), and Southwest Pacific 

 (warm and cold waters). The Atlanto-East- Pacific comprises the East 

 Pacific (warm waters). Northeast Pacific (cold waters), Southeast Pa- 

 cific (cold waters) and the Atlantic Ocean (warm and cold waters). 

 The two other provinces, the North Pacific and South Pacific, may be 

 regarded as part of the polar areas. 



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