Tree Sharpening Caterpillars

November 2nd, 2013 - 4:38 PM | Filed under Featured Photos | 1 Comment
~30mm long | January 5, 2013 | Panga Ecological Reserve, Minas Gerais, Brazil

~30mm long | January 5, 2013 | Panga Ecological Reserve, Minas Gerais, Brazil

What appears to be a flower here is actually a group of caterpillars working their way down a sapling trunk.

They look like they could do a decent job sharpening a pencil, about the same width as this tree(?) trunk.

Side view | Trunk ~5mm wide

Side view | Trunk ~5mm wide

Despite the black background, this was taken a few hours before sunset. At the time there was probably a few feet of the trunk left. I marked the location and returned after dark. I found no trace of the trunk or the caterpillars. They apparently ate the whole tree.

I know there are defoliating caterpillars. I know there are wood boring caterpillars. I never imagined there are caterpillars that consume an entire tree though. That’s assuming they eat leaves, which I didn’t observe.

Sign Challenge #1 Reveal: Spinybacked Spider Egg sac

February 10th, 2013 - 12:25 PM | Filed under Sign Challenges | 2 Comments

This reveal for Sign Challenge #1 is long overdue. Here’s the challenge photo again:

~15mm long | August 23, 2012 | Sebring, FL, USA

~15mm long | August 23, 2012 | Sebring, FL, USA

Commenter Daniel Heald correct guessed it was a spider egg sac. Here’s another angle:

Dorsal view

Dorsal view

When I took the photos, I assumed it was a cocoon. I was curious to see what moth would emerge, so I took it home with me.

After looking through Tracks & Sign of Insects and Other Invertebrates, I realized it was actually an egg sac for a Spinybacked spider (Gasteracantha cancriformis). In fact, I had seen many of those spiders in the area. The egg sac’s yellow silk, dark longitudinal line, and placement on the underside of a leaf all point to this species.

In Spiders of the Carolinas, L. L. Gaddy notes that in over twenty years of fieldwork he’s not seen the egg sac or male of this species. Perhaps I’m just lucky, but I suspect I’m more of a leaf flipper than Gaddy. The egg sacs are placed on the undersides of leaves, which is where I’m always checking for caterpillars.

I was curious to see the spider eggs, so I peeled back a few layers of the silk and found the spiderlings had already hatched. Turns out they stay in the egg sac for weeks before emerging.

Spiderlings revealed

Spiderlings revealed

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Closer look

I had hoped to see the spiderlings grow, but they all died after a few weeks.

References:

Spiders of the Carolinas
by L. L. Gaddy
Tracks & Sign of Insects and Other Invertebrates:
A Guide to North American Species

by Charley Eiseman and Noah Charney

BugShot 2012: Wolf Spiders

September 26th, 2012 - 9:55 PM | Filed under Featured Photos | 1 Comment

I enjoyed BugShot 2012, but didn’t take as much advantage of the setting as I’d hoped. By the time I got to Archbold Biological Station, I was coming down with what turned out to be an upper respiratory infection that would last for several weeks. At the end of each day I mostly just wanted to sleep. Not wanting to totally waste the opportunity, I did venture out for several hours on the final night.

Wolf spiders were everywhere and were easily found by the reflections of their eyes from my headlamp. This lighter colored one was my favorite.

Wolf Spider | August 25, 2012 | Archbold Biological Station, Venus, Fl, USA

That initial shot was more for documentation purposes to aid in potential identification later. With that out of the way,  I decided to get closer…

A closer view

and lower.

Side view

Having been stationary for awhile, my headlamp started attracting insects. The wolf spider capitalized on the situation, yielding my favorite shot.

A wolf spider with prey attracted by the photographer’s headlamp.

To get these shots I ended up chasing it around quite a bit. Each time, I’d try to carefully remove as much debris as possible from around it for a cleaner background. I got rid of the bigger bits, but there was still lots of smaller stuff left. I suppose controlling that sort of thing is one advantage of studio shots.

I ended up with a few decent shots and lots of sand all over myself and my equipment.

There were also some darker colored wolf spiders that really stood out against the white sand. When viewed amid the dry vegetation, however, they were difficult to spot.

Wolf spider camouflaged in grass

This particular spider captured my attention in a way I hadn’t expected. When you’re shining for spiders using a headlamp, you usually see just a few reflections from their large forward facing eyes. When my lamp light shone on this one, however, I thought I’d found a walking jewel. Light reflected from all the eyes of the babies she carried on her back, as if from a multifaceted gemstone!

Black-Dotted Ruddy / Holly Looper

July 23rd, 2012 - 11:10 PM | Filed under Featured Creatures | No comments

Being National Moth Week, I have every excuse to post about one of my favorite subjects. Admittedly, I get more excited about caterpillars, but I enjoy seeing the moths that most of them become.

Back at the end of April, I was distracted by something while going to check the mailbox. Actually, I’m often distracted any time I venture into my yard, but that’s kind of the point of having one for me. Anyway, some large hollies form a hedge along part of my driveway. I spotted a caterpillar dropping from from the holly to the ivy beneath it. I grabbed it for a closer look and started scanning the holly for others. I quickly found another one and brought them inside for rearing. Less than a month later, I was rewarded with a Black-Dotted Ruddy, Ilecta intractata.

25mm | May 17, 2012 | Twelvestones, Roswell, GA, USA

The common name refers to the four black dots, one centrally located on each wing, which help identify it.

The plumose antennae identify this specimen as a male.

Male, based on the feathery antennae

The caterpillars were plain green, which camouflages them well in holly foliage.

~19mm | Dorsal view of plain green caterpillar

Because of their plain appearance, I figured they would be difficult to identify. As it turns out, if I’d just cross-referenced the food plant, I’d have identified them pretty easily. The caterpillars are in fact known as Holly Loopers.

Demonstrating the source of its common name, looper.

They feed exclusively on holly, but don’t seem picky about which variety. I have a different type of holly in my backyard, and I found a dozen or so feeding on it as well. In fact, it was difficult to find a leaf that didn’t show evidence of their feeding behavior. As they feed, they notch out deep cuts.

Notching the leaf as it feeds

It didn’t spin a cocoon, so it probably pupates in soil normally. That would explain why it was dropping from the holly when I first encountered it.

10mm | Pupated around May 3, 2012

Here’s hoping that you’re distracted by a few moths this week. Just leave an outdoor light on for them, and you’re sure to be rewarded with something interesting.

References:

Peterson Field Guide to Moths of Northeastern North America
by David Beadle and Seabrooke Leckie
A Field Guide to Moths of Eastern North America
by Charles V. Covell, Jr.
Caterpillars of Eastern North America
by David L. Wagner

Yellow/Black Treehoppers with Ants

July 14th, 2012 - 9:06 PM | Filed under Featured Photos | No comments

~5mm | January 7, 2012 | Tupaciguara, Minas Gerais, Brazil

Here’s yet a different species of colorful treehopper. These too were found in association with ants.

A busy photo, but packed with natural history.

Ants Tending Treehoppers, Poorly Perhaps

July 9th, 2012 - 11:36 PM | Filed under Featured Photos | No comments

~3mm | January 7, 2012 | Tupaciguara, Minas Gerais, Brazil

I had planned to post just a single photo of this scene with ants tending treehoppers. Here we see at least two different colorful treehopper instars, with one actively molting. Ants like the one shown above tended to this small grouping of treehoppers. As I was choosing a photo to post, I noticed something strange about the treehoppers though. Do you see it too?

Look closely and you’ll see that a few nymphs have parasites. I wasn’t sure at first, so I started looking through my other photos. Sure enough, almost every one had one or more parasites. The parasites seem to prefer hiding under the wing pads and below the thorax.

Note the orange parasites hanging below the uppermost treehopper nymphs

See the parasites peeking out from beneath the wing pads of the lower nymph?

Most of the parasites were small, but there were at least a few plump ones.

Note large parasite on uppermost nymph

None of the photos provided a clear view of the parasites, but I suspect they are mites. In any case, apparently the services provided by the ants don’t include grooming.

Checkered-Fringe Prominent Rearing

July 4th, 2012 - 5:43 PM | Filed under Featured Photos | No comments

30mm | 29 October 2011 | Suwanee, GA, USA

This was one of the last caterpillars I collected last year for rearing. I generally stop looking around the end of October.

This particular caterpillar is fairly distinct and easily recognized as Schizura ipomoeae. The stripes on the head capsule are diagnostic.

Head on view

The adult on the other hand is more difficult to recognize, I think. I’d have probably given up identifying it if I didn’t already know what it was based on the caterpillar. This particular one emerged in early May.

20mm long | 11 May 2012

You might have noticed I haven’t posted anything in awhile. I get a lot of enjoyment from posting here, and I remain committed to doing so whenever possible. Lately it just hasn’t been a priority for many reasons. Hopefully, I’ll now be able to get back to posting more regularly.

Poison Ivy Caterpillar / Dimorphic Macalla Moth

May 20th, 2012 - 4:36 PM | Filed under Featured Photos | 3 Comments

For many years I’ve noticed colorful little caterpillars that live individually in silken retreats on the surface of leaves of poison ivy. At a recent BugGuide gathering, a photo of one of these caterpillars was shown and I realized we still didn’t know what these were. I resolved then to rear a few to try and arrive at an identification. There’s plenty of poison ivy near my home, so I didn’t anticipate much trouble finding a few.

Here’s the first one I found. The white area just behind the head is atypical. The caterpillar is smaller than usual, so it might be an early instar. It could also represent some sort of injury.

13mm | August 20, 2011 | Roswell, GA, USA

The next day I collected another one, larger.

20mm | August 21, 2011 | Roswell, GA, USA

The next weekend I collected one more.

20mm | August 27, 2011 | Roswell, GA, USA

Here’s a cropped version of the image above, showing the head. Checking these specimens and other photos on BugGuide, there appears to be quite a bit of variability in the head coloration. They all have a white band across the lower part of the head capsule though.

Closeup of head

At that point I figured I had a good chance of successfully rearing at least one.

The last one I collected was the first to pupate. A few days before pupating it started to change color. That’s not unusual for caterpillars as they prepare to pupate. In this case it darkened to become more orange.

Prepupal stage of final instar | 9 September 2011

Another closeup of head

I neglected to photograph any of the pupae.

Earlier this month, an adult eclosed. It’s attractive and quite distinguished looking with an elaborate headdress.

20mm wingspan | 4 May 2012

Lateral view

Front view

Closeup of head

After searching through various guides, I decided this must be what’s currently known as Macalla superatalis. My books actually identified it as part of a genus it was previously placed in, Epipaschia. The common name, Dimorphic Macalla (previously Dimorphic Epipaschia), refers to the fact that it comes in two color forms: green as above, or tan.

Having arrived at the identification, I checked BugGuide and found that someone had beat me to the identification based on a literature search. Oh well, it looks like I might be the first there to have successfully reared them though.

References:

A Field Guide to Moths of Eastern North America
by Charles V. Covell, Jr.
Peterson Field Guide to Moths of Northeastern North America
by David Beadle and Seabrooke Leckie

Tapinoma Ant Observations

May 2nd, 2012 - 10:31 PM | Filed under Featured Photos | 1 Comment

April 13, 2012 | Twelvestones, Roswell, GA, USA

For several days I had noticed ants racing along the bricks at the base of one of my garage doors. I finally took a closer look to see what could be keeping them so busy for so long. They were streaming between a hole in my house and somewhere out in the front yard. I tried following, but these ants are tiny, only a few millimeters long. I quickly lost them in some pine straw.

Moving out

Turns out they were moving out of my house. The ones heading toward the yard were carrying eggs, larvae, and pupae. As I watched them though, I noticed something else leaving with them that didn’t look quite right.

That's not an ant

When I first saw one of the critters above, I knew it wasn’t an ant. My initial thought was it must have been a tiny roach. That first one was gone before I could react, but I headed inside to grab some containers in hopes of seeing more. Over the course of an hour and a half, I spotted three more and managed to grab a couple of them.

Watching one, it seemed unsure of its course. At times it would bump against some incoming ants and dart away. It would always rejoin the column, but sometimes moving in the wrong direction.

About to right itself

Eventually it would right itself, almost always after encountering an ant carrying a larva or pupa. I’d guess it can’t follow whatever chemical signals the ants are tracking and instead relies on following the cargo.

Follow the larvae

It got me wondering how the ants know which direction to go in. I know they follow a chemical trail, but what tells them which direction they should go? Actually, lots of questions came to mind as I watched them. How do they know it’s time to move? How do they decide on a new nest location?

Later, I gave the freeloaders the white paper treatment.

Dorsal view

I began to wonder if these weren’t crickets. I grabbed Arnett’s American Insects and started skimming the cricket families listed there. When I came to Myrmecophilidae (Ant-loving crickets), I figured that must be it. I briefly thought I might even be able to contribute something to BugGuide, but it turns out there were plenty of photos there already, confirming the identification.

Dorsolateral view

Both the specimens I captured have ovipositors and so must be female.

Frontal view

Rear view

Another shot

I found some good info on these in my Field Guide to Grasshoppers, Katydids, and Crickets of the United States. These crickets only live in ants nests. They apparently feed on oily secretions from the ants bodies, causing no ill effects. Only one species occurs in my area, the Eastern Ant Cricket, Myrmecophilus pergandei. This particular cricket species has been found living with eleven different species of ants.

Speaking of ant species, I decided to try and identify the host ants. Using the key in Ants of North America: A Guide to the Genera, I arrived at Tapinoma. Based on the remarks there, I believe these ants must be Tapinoma sessile. I sacrificed one to see how well the common name of Odorous House Ant applies. It was indeed odorous, and as I mentioned, they were leaving my house.

As I watched the ant column, one other thing caught my attention. Fairly often, I’d notice a much larger ant passing by, about twice as big as the others. I snatched one of those as well.

Queen

Remembering some of Alex Wild’s comments from his blog entry on how to identify queen ants, I recognized this as a queen. That only confused me though, since I had seen perhaps half of dozen of these in the brief time I observed the column. I naively thought that ant nests generally had a single queen. The wikipedia entry for this species says that its nests can actually have hundreds of queens!

I wasn’t familiar with either of these interesting insects when I started watching them. Had I encountered them a week later though, I’d probably have recognized them from a recent post from Alex Wild. He scooped me, but I couldn’t let the opportunity to blog about them pass.

What happened to the ants you might be wondering? Well, they can’t seem to make up their mind. As I write this there is still a column going strong, weeks later. They were steadily moving out for almost a week, but then at some point I noticed they had reversed course and were moving back in. I don’t want to imagine just how many thousands of ants there are somewhere in the walls of my home.

References:

American Insects:
A Handbook of the Insects of America North of Mexico

by Ross H. Arnett, Jr.
Field Guide to Grasshoppers, Katydids, and Crickets of the United States
by John L. Capinera, Ralph D. Scott, and Thomas J. Walker
Ants of North America:
A Guide to the Genera

by Brian L. Fisher and Stefan P. Cover

Another Unidentified Caterpillar

April 30th, 2012 - 10:04 PM | Filed under Featured Photos | No comments

~30mm | January 7, 2012 | Tupaciguara, Minas Gerais, Brazil

Even though I can’t identify it, it’s pretty enough that I had to post it.