Volume III, Sumber fi 



A NEW DIADIPLOSIS 



By E. P. Felt 



The midge described below was received from Proi. 

 Wheeler accompanied by the statement that the larvae were 

 devouring mealy-bugs {Pseudococcus broyneliae Bouche) in a 

 cavity of a peculiar myrmecophilous tree, Tachigalia, in British 

 Guiana. The coccids and the fly larvae live in a cavity of the 

 leaf petiole. 



This species approaches closely that West Indian 

 Diadiplosis cocci Felt, which was reared from larvae preying 

 upon the eggs of Saisneiia nigra Nietn., a scale insect fre- 

 quently abundant upon the stems of Sea Island cotton. The 

 female of the West Indian species has a distinct knob upon the 

 terminal antennal segment and the lobes of the oviposter are 

 somewhat narrower, two characters which serve to distinguish 

 the species, though it is frequently very difficult to find charac- 

 teristic structures in female gall midges. 



Diadiplosis pseudococci sp. nov. 



Female. Length 1.25 mm. Antennae extending to the base 

 of the abdomen, sparsely haired, yellowish brown, of fourteen 

 segments, the fifth with a stem about one-fourth the length of 

 the cylindrical basal enlargement, which latter has a length 

 about two and one-half times its diameter and is slightly con- 

 stricted near the basal third ; low, broad circumfila occur on the 

 enlargement at the basal third and apically; basally there is a 

 thick whorl of rather long, stout setae and on the ventral face 

 near the distal third a rather thick group of long, rathei 

 strongly curved, slender setae ; terminal segment somewhat 

 produced, with a length nearly three times its diameter and 

 tapering gradually to a sub-acute apex (no knob as in D. cocci) 

 Palpi : the first segment short, the second with a length about 

 twice its diameter, and the third a little longer than the second. 

 Mesonotum dark reddish brown; scutellum and postscutellum 

 yellowish orange; abdomen "orange red"; the sclerites yellowisn 



