Vol. XXVIII, pp. 49-52 March 12, 1915 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



A REMARKABLE NEW THRIPS FROM AUSTRALIA. 



BY J. DOUGLAS HOOD, 



United States Biological Survey. 



The thysanopteron described below presents an interesting 

 and truly unique modification of the last abdominal segment. 

 In every other species of the suborder to which it belongs this 

 segment is slender and nearly cylindrical in form, and is always 

 termed the " tube." In the insect here described, however, it 

 is greatly swollen and its resemblance to a tube has entirely 

 disappeared. The species is generically and specifically new 

 and would appear also to represent a new family. We owe its 

 discovery to Mr. A. A. Girault, the hymenopterist. 



Family Pygothripidae nov. 



The characters upon which this family is separated from the closely 

 allied Phloeothripidee are the very transverse form of abdominal segments 

 two to nine and the structure of the tenth abdominal segment, which is 

 not at all tubular in form but is greatly swollen, and in the single known 

 species about parabolic in dorsal aspect. 



Genus Pygothrips nov. 

 (T^vyh, the rump; 6pl-i', a wood worm.) 

 Head much longer than wide, subtruncate in front, vertex evenly 

 declivous; cheeks nearly straight, with a few minute, barely visible 

 bristles. Eyes subquadrangular, larger in dorsal view than in ventral, 

 their width about equal to the interval between them. Ocelli equidistant, 

 anterior ocellus not overhanging. Antennse eight-segmented, the last 

 two segments compactly united (much as in Trichothrips anomocerus 

 Hood). Mouth cone large and heavy, formed as in Cryplothrips, nearly 

 attaining posterior margin of prosternum ; labium rectangularly rounded 

 at apex, subequal in length to labrum. Pronotum shorter than head 

 and (inclusive of coxse) more than twice as wide as long; anterior margin 

 deeply and roundly emarginate. Legs moderately short ; fore tarsi armed. 

 (Wings wanting in the unique specimen.) AVxiomen heavy; segments 



6— Proc. Biol. Soc. Wash., Vol. XXVIII, 1915. (49) 



