Bugfolks

I followed David Wagner's suggestion (in his book, Caterpillars of Eastern North America) to go out looking for caterpillars at night, with a flashlight.  It was great fun, and found two species that I had never seen before.  They are both "Slug Caterpillars", in the family Limacodidae.  I think I've identified them - they look exactly like photos in his book.

Jeweled Tailed Slug Caterpillar  (Packardia geminata)  This one is about 12mm long.  It's eating cherry leaves.  It moves slowly and smoothly, and methodically eats its way across the leaf.

Yellow-shouldered Slug Caterpillar - (Lithacodes fasciola) This one is 8mm long.  It's eating Box Elder leaves and likes to be on the underside of the leaf.  When I turned the leaf over to take its photo, it moved very quickly to get to the underside again.

I also found a Hermit Sphinx (Sphinx eremitus)caterpillar yesterday, crawling quickly across the driveway in the sun. I think this must be the last instar, and it was looking for a place to pupate.

I walked up through the woods yesterday, and saw lots of violet leaves with very distinctive insect damage.

This is one of the leaves

After searching under and around several leaves, I finally found the culprit.  It's a tiny brown caterpillar called "The Beggar" (Eubaphe mendica)  It's in one of the largest moth families - the Geometridae - often called "inchworms".

The Beggar is in the sub-family Larentiinae, whose members are called Carpets.  The adult moth is yellowish cream with gray spots.  I'd like to see if I can raise it to the adult stage.  I've got it in a container with violet leaves, and it's happily eating more holes in them.

I've seen two species of tussock caterpillars this week - in the family Lymantriidae.  One is the Milkweed Tussock Moth caterpillar (Euchaetes egle).  These guys are gregarious in early instars, and there were 6 or 8 of them clustered on one leaf on this common milkweed plant.

This is the other tussock moth caterpillar - it came in on the lilac leaves that I had picked to feed my cecropias.  I haven't been able to identify it.

The most common skipper I saw this week was the Leonard's Skipper (Hesperia leonardus).  This one was nectaring on Field Thistle (a native thistle) in one of our remnant prairies.  Field Thistle is a favorite nectaring plant for late summer insects including the beetles that were sharing this flower.

Giant Swallowtails (Papilio cresphontes) were also nectaring on the thistle flowers.

Marcie - from the farm

In looking at information about Giant Swallowtails in Wisconsin, no one seems to be sure whether they overwinter this far north, or repopulate this area from farther south each spring.

These are the dates of my first Giant Swallowtail sightings for 3 of the last 4 years.

2005 – August 10

2006 – May 29

2008 – May 23

It would be interesting to know if these were immigrants, or newly hatched butterflies from nearby.

This is a link to someone’s account of a Giant Swallowtail chrysalis surviving the winter in northern Illinois – so it seems that they do overwinter there.

Giant Swallowtails, like other swallowtails, spend the winter as a pupa (chrysalis). I watched a female lay an egg a few days ago, and thought it would be interesting to raise it and see if it survives the winter. I spent this morning checking out Prickly Ash bushes, and I found 4 more eggs and 7 early instar caterpillars.

I’ll try raising them all and see what happens.

I raise my caterpillars on our porch, which is protected from snow and rain, but not from winter temperatures. Since the pupae need moisture, I usually spray them with water when it rains, or throw some snow on them every week or so all winter.

I just read about someone who has raised Giant Swallowtails, and she says the caterpillars sometimes eat each other if they’re kept together. I usually raise caterpillars in large screened cages, so I’m going to have to adapt my system a little to keep the caterpillars separate.

To start with, I’ve done it like this.

Each caterpillar is on a branch of Prickly Ash, stuck into a florist tube, and stuck in the side of one of my large screened cages.

I’m hoping that they’ll stay on their own branches for now - they're very small and don't seem to move around much. As they get bigger, I’ll figure out a new system.

Here’s an egg.

A first instar caterpillar – it’s about 5 mm long.

I think this is a second instar caterpillar. It’s longer – 12 mm – its skin has gotten shiny, it’s lost its hairs, and its head is wider.

Marcie

A month or so ago, Ian gave me the chrysalis of what he thought was a Viceroy.

This is the chrysalis.

About a week later it hatched into a Red-spotted Purple.

A few days after that I watched a Red-spotted Purple lay an egg on the tip of a Willow leaf. They lay their eggs right at the very tip of the leaf, on the top of the leaf.

This is the egg on the leaf.

This is the egg looking through a microscope.

I looked around and found 3 more eggs - they all looked exactly the same, and were on the tips of willow leaves. I collected all four, and put them in a cage. Only one caterpillar hatched - or I missed seeing the others. But one caterpillar happily ate willow leaves, and grew and eventually made a chrysalis.

Here's the caterpillar at various stages.

Here's the chrysalis.

And here it is after it hatched - a Viceroy!

My conclusion from all this is that it's difficult to tell the two butterflies apart as eggs or chrysalises. The caterpillars of both will eat willow, and they lay their eggs in the same place on the leaf.

James Scott's book says that the chrysalises are similar except that the bump on the Red-spotted Purple chrysalis is less angled that the one on the Viceroy chrysalis. My two chrysalises confirm this difference. I'd like to raise both kinds of caterpillars sometime, so I could learn the differences between them.

Marcie

I found a Giant Swallowtail caterpillar on a Prickly Ash shrub several weeks ago. It was huge and nearly ready to make a chrysalis.

It made a chrysalis on July 22nd.

On August 11th the butterfly finally emerged.

I raised a Giant Swallowtail once before - several years ago - from an egg, so I have a few old photos of earlier instars.

This is probably a first instar:

This is a later instar - with its red osmeterium. I must have startled it when I took the photo.

We see many Giant Swallowtails on our land in Buffalo County, WI. I don't think they survive our winters - I think they repopulate from farther south every summer. The earliest I've seen one here was this summer - on May 23rd.

Here's one nectaring on Swamp Milkweed.

And here's a comparison shot - a Tiger Swallowtail and a Giant Swallowtail side-by-side.

In the summer they are one of the most common butterflies we see on our driveway.

Marcie

I went to the North American Prairie Conference this week, in Winona. It was interesting and useful, but one of the best parts was the field trip - because I could look for insects. I wanted to be in Wisconsin, so I chose a trip that visited two places near LaCrosse.

The first was Holland Sand Prairie - a well preserved 60 acre sand prairie. It's a State Natural Area, owned and managed by the Mississippi Valley Conservancy. The trip was really supposed to be about the plants, but I saw a few nice insects. Margot helped me identify them.

Here's a beautiful Common Green Darner (Anax junius) - I think it must have been newly hatched, because it was very calm.

An adult Antlion - I think it's a male in the genus Brachynemurus, because of its long abdomen.

At the LaCrosse River State Trail I saw a huge, furry caterpillar - a Salt Marsh Moth caterpillar (Estigmene acrea).

The nymph of a Leaf-footed Bug (Chariesterus antennator) - Margot says it's an unusual species - only found in native grasslands. The adults feed on Flowering Spurge.

Here's a Katydid - I think it's a Straight-laced Meadow Katydid (Conocephalus strictus).

And I saw some beautiful Japanese Beetles (Popillia japonica ). Not native, but gorgeous bugs!

The other highlight of the conference - for me - was hearing an inspiring talk by MJ about prairie insects and how citizen science can contribute to our knowledge of them. While talking to her afterwards, we came up with the idea of starting a website for all of us insect citizen scientists: Bugfolks!

Marcie

Hello world,

Here's the first Bugfolks post.