30 Nebraskaland • July 2022
into adults.
As mentioned earlier, parasitoids don't need nests because
they are laying eggs right on their hosts. That saves a lot
of time, but doesn't do much to protect their larvae, which
are feeding inside an immobile insect or spider that's lying
out in the open. There's a pretty good chance a predator or
scavenger will come pick up that helpless creature and eat
both it and the parasitoid larva within.
You may have noticed that I'm using a lot of words like
"often," "generally" and "most" as I describe wasps and their
life histories. That's because when you're talking about more
than 100,000 species, there are exceptions to pretty much
every rule.
Cuckoo wasps, for example, are pretty exceptional. These
wasps don't make their own nests or hunt their own prey.
Instead, they lay their eggs in the nests of other wasps or on
another wasp's prey when it is left unattended, sometimes
while the wasp is building a nest to put it in. Also known as
Female noble scoliid wasps (Scolia nobilitata) feed their
young with scarab beetle larvae by digging into the ground
and laying eggs on them. Males spend their lives searching
for females to mate with. Both feed on nectar from many
diff erent fl owers.
The great black wasp (Sphex pensylvanicus) caches several
paralyzed katydids in an underground nest and lays an egg
on each one. Birds sometimes harass these wasps and steal
their prey before they can get them to the nest.
Yellow-legged mud-daubers (Sceliphron caementarium) build
above ground tubular nests out of mud and fi ll them with
paralyzed spiders for their larvae to feed on. Their tubes are
often found on the sides of buildings.
The top photo shows a mud-dauber nest after the larva has
exited. The bottom photo shows the remains of a paralyzed
spider and discarded skins the wasp larva left after it grew
and molted.
