DESCRIPTIONS OF IMMATURE STAGES OF TRUPANEA-NIGICORNIS AND TRUPANEA-BISETOSA (DIPTERA, TEPHRITIDAE) FROM SOUTHERN CALIFORNIA

The immature stages of the sympatric, cryptic species Trupanea nigrico rnis (Coquillett), a flower head-infesting fruit fly that attacks a ni de range of hosts in the Asteraceae in southern California, and T. bis etosa (Coquillett), an oligophagous congener that attacks only a few h osts in the tribe Heliantheae, are described and illustrated. Detailed examination with the aid of scanning electron microscopy of the eggs, all 3 instars, and puparia of this taxonomically closely allied gener alist and specialist revealed many similarities and very few differenc es, for instance, most puparia of T. nigricornis were shelter and narr ower than those of T. bisetosa. Therefore, major differences in the ho st-plant specificities of these cryptic, possibly sibling, species wer e not reflected by substantial morphological differences among their i mmature stages.