Girl or Boy Butterfly?

It's not difficult to tell a boy butterfly from a girl butterfly. Having learned to tell the difference, one generalization that can be made (allowing for exceptions, of course) is that here in Berkeley CA the female Anise Swallowtails are generally larger than the males.

Below is a pair of butterflies getting ready for their maiden voyages. The male is the smaller of the two, on the left.

Since wingspan is not a very reliable way to tell the sex of a butterfly, it's better to use the more air-tight approach: take a careful look at the butterfly's rear end.

Below is a close-up showing the tail-end of the above female's abdomen.

There's a bit of a terminal point, but otherwise no fancy apparatus.

By contrast, the male tail is elaborate---a pair of claspers to aid in the delivery of sperm to the female, and unfortunately not very clearly shown below due to their dark color and the dark background:

They are easy to see in the real live butterfly, however, if you wait for the butterfly to spread its wings out horizontally.

There is a better picture of claspers in the section called Emergence.
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The condo, nursery, bassinet, and pupa pad...
Tools...
Time for chow...
Beware store-bought food!
The preferred foods...
Convergence...
Newborn...
Reasoning with a youngster...
Pumpkerpillars...
Twins...
A tiny wasp larva intervenes...
Don't toss out that drowned cat!
Silk...
Frass...
Something there is in a fennel plant that loves a caterpillar egg...
Cats can be a handful... Applying low voltage...
Time to roam...
Contortion...
It's pupating where??
What is that weird thing?!
Dunno--that pupa looks sort of dead...
No harness? Stop worrying...
Emergence...
The butterfly...
Girl or Boy?
The fabulous flying machine...
Full Span...
The antennae...
The proboscis...
Close-up...
Home Feeding...
Lifespan Timeline...