no functional mouthparts, short lifespans

[Donna Hurlburt]

Just to verify,

Yucca moths do not feed as adults, but they do eat quite voraciously as
larvae
on seeds within yucca fruit.  They do have rather large mouthparts as
adults!

As for longevity, our data on captive yucca moths indicate that they can
live in
excess of 9 days!  I suspect longevity is related to the length of diapause
(some yucca moths have remained in diapauce for 17 years before emerging as
adults).

Donna Hurlburt
Dept. Biological Sciences
University of Alberta
Edmonton, Alberta

DR. JAMES ADAMS wrote:

> Michelle,
>
>          As adults, there are numerous moth species with no
> functional mouthparts (though some species do have certain parts
> still visible [labial palps, etc.]).  These include all Giant Silk
> Moths (Saturniidae), though they eat so much as larvae that they
> frequently last up to two weeks (sometimes more) on the nutrients
> they stored up as larvae.  Also in this group is the also large
> Great Poplar Sphinx Moth (Pachysphinx modesta/occidentalis).
>
>         As for species living only one to a few days as adults, this
> is certainly true for some of the very small moth species, though I
> am not as knowledgeable as to which species have functional
> mouthparts and which don't.  Yucca moths, for instance, live rarely
> more than two days as adults in the lab, and I don't believe they
> actually feed on anything during that time, though I believe they do use the
> mouthparts to collect Yucca pollen to fertilize the flower in which
> they are going to lay their eggs.  Perhaps it is something along
> these lines that you read about, Michelle?
>
>          James
>