REPORT OF THE STATE ENTOMOLOGIST I917 I45 



YOUNGOMYIA Felt 



1908 Felt, E. P. N. Y. Slate Mus. Bui. 124, p. 398-99 



1910 Rubsaamen, E. H. Zeitsch. Wissenschaft. Insektenbiol., 15:289 



191 1 Felt, E. P. N. Y. Ent. vSoc. Jour., 19:53 

 1913 Kieffer, J. J. Gen. Insect., fasc. 152, p. 243 



This genus comprises a number of rather large, yellowish or 

 brownish species allied to Dicrodiplosis Kieff. and easil}' distinguished 

 therefrom by the greatly produced terminal clasp segment and the 

 thickly setose ventral plate and harpes. The male has the flagellate 

 antennal segments trinodose, the distal enlargement being distinctly 

 divided, sometimes by an appreciable stem. The palpi are quad- 

 riarticulate. Wings large, rather hairy, the third vein uniting with 

 costa well beyond the apex of the wing, the fifth near the distal 

 fourth, its branch near the basal half. The legs are long; claws 

 stout, unidentate, the pulvilH being about half as long as the claws. 

 The dorsal plate is broadly triangular, the lobes internally with a 

 few stout setae; ventral plate long, stout, broadly rounded and 

 thickly setose apically, the harpes tapering and thickly setose. Type 

 Dicrodiplosis podophyllae Felt. 



The female has the fifth antennal segment with the stem about 

 one-fourth the length of the cylindric basal enlargement, which 

 latter has a length about three to four times its d'ameter. The 

 ovipositor is short, stout, the lobes being unusually large and 

 orbicular. Rearings show that members of this genus display a 

 marked preference for floral buds, Y. umbellicola O. S. and 

 Y. vernoniae having been reared, respectively, from the 

 blossoms of the elder and ironweed. Another species, Y. q u e r - 

 c i n a, lives in a subglobular gall on the under side of young leaves 

 of the running oak. 



Key to Species 



Males 



a Abdomen reddish brown, the basal and distal portion of the stem of the 

 fifth antennal segment with a length two and one-half and twice their 

 diameters, respectively, the internal basal lobe of the basal clasp segrrent 



quadrate podophyllae Felt, C. 207 



aa Abdomen dark red, the stems of the fifth antennal segment each with a 

 length twice the diameter, the internal basal lobe of the basal clasp 



segment triangular rubida Felt, C. 423 



aaa Abdomen yellowish brown, the basal and distal stems of the fifth antennal 

 segment with a length one and one-half and two and one-half times 

 their diameters, respectively, the internal basal lobe of the basal clasp 

 segment rounded apically vernoniae Felt, C. 973 



