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

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

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.

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

References:

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.

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…

and lower.

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

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.

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!

While on my way to BugShot 2012, I spent several days exploring parks along the way. My favorite spot was the Nature Conservancy’s Tiger Creek Preserve for the variety of habitats its trails pass through.

Here, I was curious about some some palmetto leaves that had been sealed up. Peeling a layer of leaves away, I found a red widow guarding her egg sac.

On the underside of a leaf, an attractive lynx spider guards her egg sac.

This thread-legged bug appears to be hanging in mid-air, but in fact it has delicately balanced itself on a spider web. Its beak holds a small spider that it must have just plucked from the center of the web.

Some thread-legged specialize in spiders, and I wonder if this might be one of them. Some are even known to lure the spider by plucking at the web like captured prey might.

This attractively marked hunting spider spider was resting on a blade of grass after a rain. I’m being intentionally vague by saying hunting spider here, because I really don’t know how to narrow it down to even a family.

With those racing stripes, one wonders how quickly it moves.

An unidentified spider peering out from its lair in a tree branch.

Resting with its legs held together on the edge of a leaf, this spider quickly grew tired of me. After a few shots, it slipped to the underside of the leaf.

I think this is a crab spider in the family Thomisidae, perhaps a Tmarus species.

This attractive male jumping spider has some interesting hooks on his chelicerae. Take a closer look at this crop from the image above.

He really has a lot going on colorwise as well. I imagine those banded front legs might be used in some sort of courtship ritual. One has to wonder if and when those hooks come into play though.

 

These two photos of critters both 4mm long were taken less than an hour apart in spots just a few feet apart. I believe these two are probably a mimic and its model.

I first photographed the jumping spider. I only got a few shots before I lost it. Later I spotted the ant and took quite a few photos. Here I selected one that would show roughly the same pose as the spider.

The area around the rearmost eyes of the jumping spider is darkened to better match the larger black eyes of the ant. The dark spots on the spider’s abdomen are an anomaly though. Maybe this ant isn’t the model after all?

I’ve actually seen many tiny jumping spiders like this one in parks around my house. I got somewhat obsessed late last year after finding the first one. Once I started looking, they were really quite easy to find on the undersides of sycamore leaves. That’s the subject of another post though.