14 



U.S. NATIONAL MUSEUM BULLETIN 2 55 



The transition from a capsular feeding larva to one that bores 

 exclusively in the stem also seems evident within the "marginatus" 

 group of the genus Prodoxus (see p. 71). On morphological evidence, 

 the adults of both Prodoxus marginatus and P. pulverulentus are 

 considered less specialized than P. aenescens. It is interesting to 

 note in this regard that the larvae of the former feed primarily in the 

 fleshy part of the young fruit or receptacle, whereas the larvae of P. 

 aenescens are restricted to the flower stalk. 



Agavenema 



Parategeticula 



Mesepiola 



Prodoxus 



Tegeticula 



HYPOTHETICAL INCURVARIINE 

 ANCESTOR 



Diagram 1. — Generic relationships of the Prodoxinae. 



Other evidence further suggests that Tegeticula represents a group 

 more ancient than Prodoxus. The larvae of Prodoxus are more special- 

 ized in that all legs have been lost; the larvae of Tegeticula, on the other 

 hand, still retain well developed thoracic legs. A comparison of the 

 prodoxine head also reveals some evidence of specialization. The 



