RANDALL: SURVEY OF CIGUATERA AT MARSHALL ISLANDS 



Figure Al.—Scarus rubroviolaceus, 355 mm SL, 1.35 kg, Enewetak, Marshall Islands. 



FIGURE 48.— Acanthurus xanthopterus, 400 mm SL, 2.3 kg, Enewetak, Marshall Islands. 



the genus Acanthurus. It is one of a complex of 

 species with a gizzardlike stomach. In the Mar- 

 shall Islands it could only be confused with A. 

 mata, also a large species. The outer third of the 

 pectoral fins of A. xanthopterus are yellowish (fins 

 uniform brown on A. mata), and there are about 4 

 lengthwise bands in the dorsal fin (about 8 in the 

 fin of A. mata); there are fewer gill rakers (16-22 

 for A. xanthopterus, compared with 21-25 for A. 

 mata). This species is distributed from east Africa 



to the eastern Pacific. It occurs more in lagoons 

 and bays than exposed outer reef areas, and it 

 ranges into deeper water than other Acanthurus 

 in general. Also it ventures farther from the cover 

 of coral reefs than other species. Schultz in Schultz 

 and collaborators (1953) used the name Acan- 

 thurus fuliginosus Lesson for this fish, but there is 

 no basis for equating it to Lesson's illustration and 

 description, as explained by Randall (1956). The 

 junior synonym Teuthis crestonis Jordan and 



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