DEEP-WATER BIOLOGICAL PROVINCES OF THE INDO-PACIFIC 



By Rolf L. Bolin 



Hopkins Marine Station 

 Stanford University, Pacific Grove, California, U.S.A. 



The bathymetric range o£ so-called bathypelagic fishes, based on 

 the questionable data from the open nets in which they are normally 

 taken, is not definitely established. In attempting to use myctophids 

 and other "bathypelagic" fishes as indicators o£ biological provinces, 1 

 have come to the conclusion that most of them tend to be distributed 

 in relation to the water temperatures of the upper 200 meters, and that 

 they must be considered as primarily inhabitants of the superficial 

 layers. 



Abyssal bottom fishes are so rare that they do not lend themselves 

 as satisfactory subjects for zoogeographical investigation, and some of 

 them give hints of practically cosmopolitan distribution— a corollary of 

 the widespread uniform habitat of the great depths. 



It is therefore among the archibenthic fishes that evidence as to the 

 limits of comparatively deep-water biological provinces must be sought. 

 The large, widespread, almost exclusively archibenthic and compara- 

 tively well-investigated family Macrouridae provides convincing data 

 on which it is possible to establish definite provinces in the 200 to 2000- 

 meter layers of the Indo-Padfic, which area I propose to treat in its 

 broad sense as including both oceans in their entirety. 



The Antarctic Province is a circumglobal region of very low tem- 

 perature bordering Antarctica. Its northern limits, in the intermediate 

 depths, lie at approximately 45° south latitude, well north of the sur- 

 face Antarctic Convergence. This province boasts no archibenthic mac- 

 rourids, although two abyssal species, Nematonurus armatus and Lio- 

 nurus filicauda, occur there, and the latter is apparently restricted to it. 

 This province has no northern Indo-Pacific counterpart. 



Immediately to the northward of the Antarctic Province lies the 

 Antiboreal Province, some 10° to 20° in width and including the 

 southern coasts of Australia and most of New Zealand. This province 

 is characterized by water of moderate temperature in the intermediate 

 depths. At least one species, Coelarhynchus fasciatus, extends its range 

 throughout the entire province, being known from off the Cape of 

 Good Hope, southern Australia, Tasmania and southern Chile. Several 

 species— Macrur onus novae-zealandiae, Coryphaenoides denticulatus, Coe- 



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