418 U.S. NATIONAL MUSEUM BULLETIN 2 02 Vol. 2 



Suborder Stromateina 



Family STROMATEIDAE: Butterfishes 



By Leonard P. Schultz 



Genus PSENES Cuvier and Valenciennes 



Psenes Cuvier and Valenciennes, Histoire naturelle des poissons, vol. 9, p. 259, 

 1833 (type species, Psenes cyanophrys Cuvier and Valenciennes). 



Considerable time has been spent in an attempt to identify the 

 specimen of Psenes in these collections but descriptions are too brief 

 and inadequate in the literature to enable me to come to a satisfactory 

 conclusion as to the correct scientific name to apply to this specimen. 

 Since this genus has never been revised and the specimens and species 

 available to me are not in sufficient numbers to make it worthwhile 

 to revise this genus, I have identified it only to the genus. 



PSENES ep.7 



SPECIMEN STUDIED 



Marshall Islands: Lat. 09°00' N.; Long. 168°00' E., U.S.S. Laffey, 1946 

 M. W. Johnson, 30 mm. in standard length. 



Description. — Dorsal IX, 1, 24; anal 111,24, scales rows crossing lat- 

 eral line 61 or 62, with 9 scales from lateral line to dorsal origin and 

 21 scales from lateral line to anal origin; pectoral rays ii,17-ii,17; gill 

 rakers 8+1 + 18. Depth 1.8; head 2.7; both in standard length. 

 Eye 3 in head. 



Color in alcohol. — Background light brown; pelvics blackish; first 

 dorsal blackish. 



Remarks. — Cuvier and Valenciennes described Psenes guamensis 

 from Guam. They record the fin rays as: Dorsal IX,I,22 ; anal "2/29" 

 which may be 111,28; caudal 17; pectoral 19; pelvics 1,5. The num- 

 ber of scales are not given. The figure of 28 or 29 soft rays in the 

 anal fin is too many to identify our specimen with guamensis. Two 

 other species may be close to this Marshall Island specimen: One is 

 Psenes chapmani Fowler from the Atlantic which is said to have 60 

 scale rows, dorsal rays X,I,23, and anal rays 111,25; the other is 

 P. maculatus Liitken, also of the Atlantic with about the same number 

 of fin rays. 



