SOME BRACONID AND CHALCID FLIES FROM FORMOSA 

 PARASITIC ON APHIDS 



By A, B. Gahan, 



Of the Bureau of Entomology, United states Department of Agriculture 



The material upon which the following notes and descriptions are 

 based was sent to the United States Department of Agriculture for 

 identification by T, Shiraki, of Taihoku, Formosa. Very little infor- 

 mation occurs in the literature concerning the parasites of plant lice 

 from this region, and it is, therefore, a pleasure to be able to make 

 this small contribution toward such knowledge. The following rec- 

 ords are especially valuable because in every instance the material 

 was reared and is accompanied by a definite host record. 



Superfamily ICHNEUMONOIDEA 



Family BRACONIDAE 



Subfamily Aphidiinae 



APHIDIUS ERVIHaliday 



Four specimens which appear to be this species were reared from 

 Macrosi'phu?n, species on Ruhns at Taihoku, Formosa, by R. Taka- 

 hashi, December 2, 1923. 



APHmiUS UNILACHNI, new species 



Differs from all other species laiown to the writer by the very 

 slender and slightly upturned ovipositor sheaths. 



Female. — Length 2.2 mm. Smooth and shining, the first tergite 

 very weakly rugulose. Head transverse, a little broader than the 

 thorax, distinctly narrowed behind the eyes; eyes very slightly con- 

 verging anteriorly; distance from antennae to apex of clypeus 

 nearly equal to shortest distance between the eyes; palpi short; an- 

 tennae 16-jointed, the third joint approximatel}^ twice as long, as^, 

 thick and the following joints, except the last, of about the sam^ 

 length as the third, last joint nearly twice as long as the tliirdr 



No. 2657.— Proceedings U. S. National Museum; Vol. 70, Art. 8. 



18120—20 1 



