30 U.S. NATIONAL MUSEUM BULLETIN 2 55 



Thorax: Wings (fig. 45) relatively broad, apices subacute, some- 

 times rounded; all veins normally separate; frenulum prominent, 

 simple in male, usually consisting of 2-3 weak bristles in female. 

 Epiphysis present (fig. 58). 



Abdomen: Female with abdomen usually laterally compressed as 

 in other Prodoxinae, depressed in T. synthetica; apex of seventh 

 tergite (figs. 115-116) unmodified, without any terminal process. 



Male genitalia. — Apex of tegumen bilobed. Vinculum V- to 

 Y-shaped; saccus slightly to well developed. Valves variously lobed; 

 lobes usually bearing short, stout spines. Aedeagus relatively short 

 and robust to elongate and very slender. 



Female genitalia. ^ — Apex of ovipositor spear-shaped; a subapical 

 dorsal ridge either present or absent. Apophyses very long and 

 slender. Ductus bursa very long, usually exceeding length of apophy- 

 ses, with an inflated portion (spermatheca) bearing two, rodlilve 

 apodemes; juncture of ductus bursa with oviduct either at spermatheca 

 or more caudad. Signa paired, stellate, with over 40 rays per signum. 



Larva (fig. 24). — Head partly retracted into prothorax, concealing 

 rear portions. Body usually pinkish m color, at least by maturity; 

 thoracic legs present, typically 4-segmented, with a single minute 

 apical claw; abdominal prolegs absent. Seed borers in fruit of Yucca. 



Pupa (fig. 26). — Head with frontal beak greatly reduced. First 

 7 abdommal tergites with a singly, prominent row of stout spmes per 

 segment; those of first tergite greatest in length, then gi'adually 

 decreasing in length posteriorly. Pupation occurs in an earthen, 

 silk-reinforced cocoon underground (figs. 29-30). 



Life History 



Egg. — The eggs of the various species of Tegeticula are probably 

 at least superficially similar, but only those of T. yuccasella have 

 been described. According to KUey (1892a), the egg is threadlike 

 in general appearance, averaging approximately 2 mm in length and 

 less than 0.1 mm in diameter. One end (wherein the embryo develops) 

 is enlarged and gradually tapers posteriorly, forming an elongate 

 pedicel. The eggs of all species are inserted singly into the ovary 

 of the plant host by means of the female's piercing ovipositor. 



Larva. — The eggs of T. yuccasella reportedly hatch in about a 

 week, giving rise to tiny larvae approxunately one mm in length. 

 The newly emerged larva may subsist for a brief period as a sap 

 feeder, but soon enters a developing ovule through the fmiicular 

 base. Body color at first is a translucent white which becomes in 

 time more yellowish and finally, at maturity, a pinkish to reddish 

 hue. All larvae of Tegeticula are characteristic in possessing weU- 

 developed thoracic legs and in lacking prolegs. 



