22 U.S. NATIONAL MUSEUM BULLETIN 2 02 Vol. 3 



PTEROIS RADIATA Cuyierand Valenciennes 



Plate 125, A; Figure 138,/i 



Pterois radiata Cuvier and Valenciennes, Histoire naturelle des poissons, vol. 4, 

 p. 369, 1829 (type locality, Society Islands). 



SPECIMENS STUDIED 



Bikini Atoll: 7 stations, 14 specimens, 28 to 83 mm. in standard length. 



Eniwetok Atoll: 1 station, 1 specimen, 51 mm. 



Rongelap Atoll: 1 station, 1 specimen, 60 mm. 



Rongerik Atoll: 1 station, 1 specimen, 37 mm. 



Kwajalein Atoll: 1 station, 2 specimens, 15 to 18 mm. 



Guam: 1 lot, 1 specimen, 49 mm. 



Description.— T>orssi\ rays XII,11 in 7 specimens; anal 111,6 in 7; 

 pectoral 16 in 7 and 17 in 4; vertical scale rows 50 to 52 from upper 

 edge of gill opening to midbase of caudal fin and usually about 25 pores. 



Depth 2.9 to 3.2; head 2.4 to 2.6; both in standard length. Snout 

 3.7 to 3.8; eye 2.9 to 3.2; postorbital part of head 2.1 to 2.2; least 

 depth of caudal peduncle 3.2 to 3.8; longest dorsal spine 0.7 to 0.8; 

 length of maxillaries 2.7; all in length of head. Least width of bony 

 interorbital 1.8 to 2.0 in eye; least depth of caudal peduncle in its 

 length 1.6 to 1.7; next to last dorsal spine in last dorsal spine 1.3 to 

 1.4 and in longest dorsal spine 3.5 to 4.7; length of first anal spine 

 in second 1.7 to 2.0; pelvics reach a little past anal origin; head ui 

 longest ray of pectoral fin 2.4 to 3. 



Color in alcohol. — Ground color whitish with 8 vertical dark bars; 

 the first from below eye across lower part of gill cover; second just in 

 front of parietal spines and fading behind orbit; third from parietal and 

 nuchal spines across operculum; fourth from first to third dorsal 

 spines to behind pectoral base; fifth from fourth to sixth dorsal spines 

 to abdomen, a little behind pelvic bases; six from seventh to tenth 

 dorsal spines to abdomen, a little in front of anus; seventh from first 

 to fifth soft ray of dorsal to front of anal fin; eighth black bar from 

 between sixth and seventh to tenth soft rays of dorsal fin to rear of 

 anal fin. A lengthwise dark bar occurs on side of caudal peduncle; 

 a round white spot at upper edge of pectoral base usually prominent; 

 blackish pigmentation on pelvics and pectorals, usually separated by 

 a white streak; lower parts of head and breast in front of pelvics white; 

 supraorbital tentacle plain blackish, margined with white and tips 

 white. 



Ecology. — This species was found where there were holes in coral 

 growths furnishing protection or hiding places under large blocks of 

 coral. When these blocks were turned over, Pterois became visible. 



Remarks. — P. radiata is the commonest species of tiger fish in the 

 northern Marshall Islands and perhaps in the shallow reef waters of 



