Out of the Eggs

In the last blog, Difficult Delivery, we saw a wind battered pipevine swallowtail struggle to put all her eggs clustered together on one leaf petiole.  I decided to follow their course through larva-hood, a dangerous time.

Egg clusters only on this petiole

On the pipevine plant sprawling on the fence, there were now 4 leaves with 10-12 eggs each, all on the very bottom strand of leaves as seen above.  This isolated location exposed to potential predators puzzled me until I read that they lay their eggs in clusters on leaves exposed to sunlight.  With our nighttime temperature dropping into the 40s, the need for a sun warmed leaf makes more sense.

 One of the original clusters had already hatched and there was no remaining evidence of the eggs.  The first instar caterpillars are initially gregarious for reasons that only they know.  The caterpillars were bunched together on a nearby leaf, apparently full from their enriched egg shell meal and not yet ready to chow down on a leaf.


On a nearby leaf petiole, a group of first instars which had eaten their way out of the eggs watched as the last hatchling was still chewing on an egg shell.  As mentioned in the last blog, the females add nutritious knobs on the outside of the eggs, giving the young cats a head start before they become vegetarians.  You can see some of the action in this video.



I returned to an egg cluster an hour later to try and get better photographs and found a new visitor.  This is a green lacewing larva, Chrysopa oculata, which is chowing down on the egg cluster.  It was sucking out the juices so there wasn't anything to video unless it was making a faint slurping sound like working on the last of a milk shake.  You can see a little dark drop that doesn't bid well for the egg.

  "My, what big jaws you have." - Harvey Schmidt

The larvae are called “aphid lions” as they can consume over 200 aphids per week.  They are predators of a wide variety of soft-bodied insects and mites, including insect eggs and small caterpillars.  They have oversized sickle-shaped jaws that  can inject prey with a paralyzing venom and then suck out the body fluids. 

Green lacewing species - Jon Rapp

Lacewing Eggs - John Meyer

In this previous blog we discussed green lacewings and their eggs which dangle on fine strings.  It included graphic scenes of violence against aphids and I know what would be in store for these swallowtail eggs.  Most of these eggs will become victims of the food web with an occasional one surviving to mate and reproduce.

Now I am invested in these eggs and I feel a parental obligation for their safety, the result of my excessive levels anthropomorphism.  I used a blade of grass to push the lacewing larva off onto the ground. It may make its way back up the stem but at least I gave it a fighting chance.
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Harvey Schmidt has a great set of Lacewing photographs here