REVISION OF MOTHS OF PRODOXINAE 69 



with tegumen bilobed). Aedeagus relatively stout, not greatly 

 elongated. 



Female genitalia.— Apex of ovipositor spearlike, dorsal ridge 

 serrate. Apophyses long and slender. A pair of signa normally 

 present, usually stellate, with less than 20 rays, signa absent in 

 P. intricatus. Ductus bursa relatively short, usually not exceeding 

 length of apophyses; spermathecal enlargement typically present at 

 union of oviduct. 



Larva (figs. 21, 22).— Head usually retracted slightly into protho- 

 rax. Body white, often becoming pale green at maturity; apodal. 

 Stem borers in Yucca. 



Pupa (fig. 25).— Head with a prominent frontal beak. Abdominal 

 tergites finely spined. Pupation occurs in a silken cocoon (fig. 28) 

 within host plant. 



Life History 



Egg. — As in Tegeticula, this stage has been described for ©nly one 

 species, Prodoxus quinquepunctellus. Is is likely that the eggs of the 

 other species wiU be similar. The egg of P. quinquepunctellus is 

 characterized as being soft, white, and somewhat variable in shape, 

 but usually compressed and elongate, measuring approximately 

 0.4 mm in length and less than 0.1 mm in diameter. Both ends are 

 rounded, and no pedicel is present. 



The egg is deposited most frequently in the yucca stalk at a depth 

 of about 1-2 mm, but may also be found in the flower pedicel or 

 young ovary. 



Larva. — The egg of P. quinquepunctellus hatches approximately 

 nine days after oviposition. The larvae of all species are apodal and 

 burrow most frequently into the main flower stalk; some species 

 burrow in the flower stems or in the fleshy parts of the fruit. In the 

 early stages, the larvae are whitish in color, often becoming pale 

 green with maturation. Except for the absence of legs, the mature 

 larvae of most species are of a typical lepidopterous form; those of 

 P. quinquepunctellus (fig. 21), however, attain a much greater relative 

 diameter and superficially resemble the larvae of some weevils. 



Riley (1892a) noted that the larva of P. quinquepunctellus undergoes 

 three molts within the normal growth period of about 30 days. Oc- 

 casionally the length of the larval period may be greatly extended, as 

 has been observed also m Tegeticula. Riley (1894) reported one 

 incident in which larvae of a species of Prodoxus had sui'vived for 

 nearly six years. The yucca stems containing these larvae were 

 collected September 20, 1893, by Mr. Albert Koebele. Over five 

 years later (May 17, 1887), the stems were cut open, and two healthy 



