Saturday, August 20, 2016

Gray blister beetles

Yesterday evening, James suggested that we go finish a project that involved peeling off letters from a roadside sign less than a mile away on Ranch Road 1623 in Blanco. Good idea! So I sprayed on some insect repellant, he put on long pants, and off we went. When we got to the site, right away I noticed some mounds of buffalo burr (Solanum rostratum) in bloom. I think buffalo burrs are pretty, but most would consider the species a weed because of its prolific prickles and toxicity. The plant is a member of the nightshade family (Solanaceae), like tomatoes and datura.

When I peered closer, I observed LOTS of long gray beetles feasting away on the leaves and even the flowers. Naturally, after we finished our job, James drove me back to the house so I could grab my camera. This was just too interesting not to document.

I've since learned–thanks to and entomologist Mike Quinn–that these are gray blister beetles (Epicauta albida). Mike pointed me to his Blister Beetles of Texas and Important Texas Beetle Resources pages. 

Normally, I'm game to handle most beetles. But something about the ferocious-looking appearance of these warned me not to. So I didn't. And good thing I stuck with my instincts. "Are they safe to handle?" I asked Mike. No. "Blister beetles are known to cause blister outbreaks," he replied. Hence, their common name.

This irritating ability comes from their hemolymph (an insect's version of blood), which triggers blistering on contact with human skin. The blistering agent is called cantharidin, which can be highly toxic to mammals. Horses have died by eating blister beetles trapped in baled alfalfa hay. For humans, the blistering is uncomfortable but soon diminishes on its own with no medical treatment.

Online, I found an extensive research study on the species, "Ecology, Behavior, and Adult Anatomy of the Albida Group of the Genus Epicauta.) Most of the study was over my head, but I did pick up some bits and pieces.   

"Adults of all species of the group are found most frequently and in greatest abundance along roadsides, near ditches, in swales, and in other situations where the amount of soil moisture is sufficient to support the growth of herbaceous plants through the summer season," the study states. "Many of the food plants of the adults are to palatable to range animals, and adults may occur in great numbers even in heavily grazed pastures and ranges. Indeed, because of the variety of weedy plants utilized by the adults, it seems likely that the group has benefited from both grazing of livestock and cultivation of the land."

The study goes on to state that the preferred food host are plants in the nightshade family, most importantly those in the Solanum genus. 

Also, adult beetles "are characteristically gregarious... Within aggregations or groups, adults commonly rest, feed, clean and perform other activities in close proximity to other individuals..."

Check, check, check! Our gray blister beetles were definitely feeding together on Solanum along a road. So interesting! Right? 

Tuesday, August 16, 2016

Black widow

Last weekend, Blanco science teacher Pam Meier messaged me the photo above and asked what it was. I knew it was a black widow, but the red markings top her abdomen were new to me. I've only seen black widows with the characteristic red hourglass marking on their tummies. 

Monday evening, she brought me the widow in a plastic drink bottle. I transferred her into a glass jar with a piece of cardboard so she could climb onto something. The feet of cobweb spiders are only designed to crawl on webs, not glass (a jumping spider could have climbed up the inside of the jar). I caught her a small moth that night and figured she'd be fine. I was sort of looking forward to keeping a spider at my desk, like I used to do years ago.

Little did I know that James had "prayed to Jesus about this and this morning my prayer was answered." He wanted my spider lady to DIE. And SHE DID! One minute, she was hanging upside down in her paper roll, and an hour or so later, she was curled up at the bottom of the jar! (So the little moth lived to see another day outside.)

Sigh. Well, I decided I might as well get her to lie in state so I could shoot some images for my collection. So there she is!  

In the meantime, I queried to ask about which widow species this one might be, and so far Jeff H. has said western black widow (Latrodectus hesperus). 

Monday, August 15, 2016

WHAT? It's the middle of August in TEXAS!

Temp reading taken at 6:50 p.m.

Common house spider

This afternoon, I accidentally knocked this gal down from a dial where she'd been perching on our dryer in the garage. I was going to let her go, but then I decided to shoot some photos. I don't have too many cobweb spider images in my collection. So meet a common house spider (Parasteatoda tedariorum). Isn't she pretty? In the bottom photo, my flash lit up her itty bitty eyes. Though cobweb spiders have four pairs of eyes, they have terrible eyesight. That's because they rely on prey to bumble into and get tangled up in their messy webs. They don't stalk victims, like jumping spiders do. Therefore, jumping spiders have GREAT eyesight. 

Winged things

I'm behind in posting photos from our Wildscape. Catch-up day since we're getting (GLORIOUS) rain! This huge swallowtail sipped awhile on our 'John Fanick' phlox July 31. Would you agree that this is an eastern tiger swallowtail (Papilio glaucus)? 

And look what I spotted August 3, relaxing on a tomato cage that we put around our Texas milkweed. I'm pretty sure this is a feather-legged fly (Trichopoda lanipes). The hairy back legs caught my eye so I ran into my house for the camera. I barely got these shots before it took off.

This pretty Texas hackberry emperor (Asterocampa celtis antonia) took a break on some ball moss in a live oak. (I had to get help from to correctly identify this butterfly. I originally thought it was a "plain" hackberry emperor.)
I was keeping this large wasp nest in the 'Eyelash' salvias in the back yard a secret from James until he was about to send a spray of water right in their direction. He took the news rather well and suggested that I get a photo of everybody. Which I did. These are paper wasps tending to their motherly business out of the way in the foliage and bothering no one. So that's why I figured they could stay.
We have only one yellow garden spider in our Wildscape this year. Here's a close up of her stabilimentum that runs down the middle of her orbweb. Biologists go back and forth over whether the zig-zag pattern attracts insects or helps to defend the spider. Only the spiders know for sure!

Wednesday, July 27, 2016

Seeds spread

Now's a good time to throw out seeds in the Meadow since James mowed this week and we're getting a little moisture, too. After my spider presentation in Kerrville Monday, Texas Master Naturalist Tony Plutino gave us some American basket-flower seeds from his Mason property so I spread those around. I also had some standing cypress seeds in a paper sack from last year so I threw those out, too. We'll see what spring brings! 

Spider presentation

Many thanks to Floyd Trefny and his fellow members with the Hill Country Master Naturalists chapter for hosting me in Kerrville Monday evening. For nearly an hour, I got to talk about "Spiders of Central Texas" in front of a captive audience of about 65 people, which included my mother, Marcelle. It was her first time to hear me speak on my favorite subject. James came, too. A good time was had by all!