GOPALAKRISHNAN: ZOOGEOGRAPHY OF NEMATOSCELIS 



Nematoscelis atlantica 



• I -24% OF THE SAMPLE 



Figure 8. — Distribution of Nematoscelis in the Atlantic Ocean based on plankton samples: b - A'^. 



atlantica. 



Current and caught frequently in mid-water 

 trawls in the San Diego Trough area. This species 

 was also caught in the Gulf of California by the 

 Vermilion Sea Expedition; however, this popula- 

 tion is believed to be separated, perhaps season- 

 ally, from that on the west side of Baja California 

 due to the influx of warm water from the south at 

 the mouth of the Gulf (Brinton, 1962). Literature 

 records and present evidence indicate that the 

 ranges of A'^. megalops and A'^. difficilis do not 

 overlap. 



Geographical Distribution of 

 IV. atlantica 



Indian Ocean 



This species has not been reported previously 

 from the Indian Ocean. In the IIOE collections 



there were frequent occurrences of this species, 

 but only in the midlatitudes (lat. 15°-40°S) 

 of the Southern Hemisphere (Figure 9a, b). 

 Nematoscelis atlantica lives in the region of the 

 Indian Ocean central water mass. Larvae and 

 juveniles were caught from most stations occupied 

 within the range of distribution of the species. 

 Moreover, there were no obvious differences be- 

 tween seasonal distributions. IIOE samples in- 

 cluded many adults from west of Australia and the 

 Agulhas Current (Figure 10a, b). In the mid- water 

 trawls it was caught between lat. 11°S and 42°S 

 along long. 60°E (Figure 11a). 



Atlantic Ocean 



Nematoscelis atlantica was observed in many 

 samples from the North Atlantic (Figure 8b). Un- 



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