122 MISC. PUBLICATION 17 4, U.S. DEPT. OF AGRICULTURE 



DESCRIPTION 



In size and structural characters Tumidiscapus flo.vus is very 

 similar to Centrodora speciosissima, but it is easily distinguished 

 from that species by the nearly uniform yellow color of its body 

 and the absence of any cloud in the fore wing. Structurally it 

 differs in the female by having the fourth antennal joint as long as 

 the fifth and by having the ovipositor less strongly exserted, while 

 in the male the antennal scape is much more strongly thickened and 

 the funicle joints are differently proportioned. 



Female. — Length 0.75 to 1 mm. Head a little broader than thorax ; vertex 

 and f rons very finely punctate ; cheeks nearly smooth ; mandibles each with 

 three teeth ; eyes bare. Antennae 6-jointed, inserted near the mouth ; scape 

 cylindrical ; pedicel about half as long as scape and about as thick as scape ; 

 first funicle joint obliquely truncate at apex, its ventral margin fully twice 



Figure 27 — Turn idisca pus flavus Girault : A, Antenna of female; B, antenna of male. 



X 270. 



as long as its dorsal margin and a little longer than the width of segment; 

 second funicle joint about one and one half times as long as broad, broader 

 at apex than at base ; third funicle joint about as long as second but thicker, 

 broadest at apex and about as broad as long; club a little thicker than third 

 funicle joint, longer than the three funicle joints combined, about equal in 

 length to the scape, solid, its apex a little curved ; elongate sensoria apparently 

 lacking. Thorax dorsally with weak granular sculpture ; prothorax short ; 

 mesoscutum about one and one half times as broad as long, apparently with a 

 very delicate median groove and with a row of three or four short setae on 

 each side of the middle, the parapsidal grooves complete and deeply impressed ; 

 scutellum about as broad as long or a little broader, rounded in outline, slightly 

 convex, apparently with a very weak median groove and with four setae ; 

 axillae small and widely separated ; propodeum a little shorter than scutellum, 

 apparently smooth, always collapsed in dead specimens. Legs normal ; tarsi 

 5-jointed. Wings well developed ; fore wing extending beyond apex of ovi- 

 positor, three times as long as broad, mostly bare basally for the length of 

 submarginal vein, ciliated elsewhere except for a narrow hairless area extend- 

 ing from the apex of stigmal vein obliquely inward and caudad but inter- 

 rupted before reaching posterior margin of wing ; marginal cilia moderately 

 long ; marginal vein a little longer than submarginal ; stigmal vein short and 

 sessile; postmarginal vein absent. Abdornen longer than head and thorax, 

 conic-ovate, broadly sessile, smooth ; ovipositor extending slightly beyond apex 

 of abdomen. Color pale reddish yellow throughout, the head above and the 

 abdomen usually a shade more reddish than the thorax, antennae and legs 

 usually very slightly paler than the body ; wings perfectly hyaline, venation 

 yellowish. 



