100 U.S. NATIONAL MUSEUM BULLETIN 255 



Thorax: Wings (fig. 49) relatively narrow, apices acute. Forewing 

 with all veins separate, hind margin slighly excavate between lb and 2. 

 Hindwing with 5 and 6 stalked about half their length; frenulum 

 simple in male, prominent. Epiphysis present (fig. 57) . 



Abdomen: Elongate, slender; seventh tergite of female simple 

 (fig. 114). 



Male genitalia. — Tegumen with apex bilobed; a pair of tiny, 

 sclerotized spots near middle of dorsal membranous area. Vinculum 

 Y-shaped; saccus well developed, elongate. Valves with sacculus 

 produced into a large, rounded lobe; beyond sacculus, valves greatly 

 constricted, with a prominent, digitate lobe, bearing a dense crown 

 of stout spines, arising from ventral margin. Aedeagus elongate, 

 slender. 



Female genitalia. — Apex of ovipositor spear-shaped, with a ser- 

 rated, dorsal ridge. Apophyses very long and slender. Signa absent. 

 Ductus bursa very short, less than half the length of the apophyses; 

 spermathecal evagination present at juncture with oviduct. 



Larva (fig. 23). — Head slightly retracted into prothorax. Body 

 white in early instars, usually becoming pale green at maturity; 

 apodal. Stem borers in Agave. 



Pupa (fig. 27). — Head with a frontal beak similar to Prodoxus. 

 Abdominal tergites each with a single row of minute spines. Pupa- 

 tion occurs in a papery cocoon within host plant. 



Life History 



Relatively little is known about the biology of this group of moths. 

 In general, their life history appears to bear close resemblance to that 

 of most stem boring members of the genus Prodoxus. 



The egg, as far as known, is always inserted into the stem, and the 

 entire larval stage is passed as a borer in the soft pith of the agave 

 flower stalk. Prior to pupation, the larva constructs an exit tunnel 

 toward the outer surface of the stem, leaving a thin partition intact to 

 block the future exit. The overwintering stage has not been noted, 

 but it is probably the last larval instar. 



Pupation takes place inside a somewhat papery cocoon, constructed 

 in the burrow usually just under the siu^face of the stem (fig. 27). 

 When ready to emerge, the pupa forces its way through the thin 

 partition blocking the exit of the burrow until its body has protruded 

 about two-thirds its length from the stem; after this position has been 

 attained, the adult emerges. Recently infested stalks can sometimes 

 be observed with numerous pupal remains protruding in this fashion. 



The distribution of this genus is undoubtedly much more extensive 

 than is indicated by present records. The author has collected nu- 

 merous larvae of a species of Agavenema from the flower stalks of a 



