Daily Archives: June 6, 2012

Tales From The Ranch: Introducing Dasymutilla klugii

While wandering around the ranch, the Czarina and I ran into an old friend, well, enemy, from my adolescence. We were tromping around close to the bank on the Brazos river, and spotted and surprised a rather interesting lizard. While circling around to get a photo so I could ID it later, she suddenly exclaimed “What the hell is THAT?” In a small sapling was what initially appeared to be a rust-colored ball of fluff, and the fluff was moving. That’s when we had a reminder that cowbirds weren’t the only parasites on the ranch.

Dasymutilla klugii

That fuzzball is most likely a female Dasymutilla klugii, commonly known as a velvet ant. Velvet ants are members of the family Mutillidae, part of the same superfamily of insects that includes wasps, stinging ants, and hornets. The velvet ants are flightless wasps found through North America, but they’re rarely seen by most people. It’s not that they’re incredibly rare, but that a combination of rough habitat and a tendency to stay away from human habitations means that they’re not encountered all that often.

More velvet ant

Eric Grissell’s book Bees, Wasps, and Ants: The Indispensable Role of Hymenoptera in Gardens still qualifies as one of the best general interest books on wasps published in the last fifty years, and even it doesn’t have all that much on velvet ants. That lack of knowledge is due to their being poorly studied. What’s known for certain is that they tend to be exoparasites of exoparasites. Many species take advantage of hunting wasps’ industriousness by waiting until a mother wasp digs a nesting gallery, gathers paralyzed prey to feed her young, and lays an egg atop said host. The velvet ant sneaks into the gallery while the mother wasp is away and lays its own egg next to the wasp’s egg. The velvet ant larva hatches first, and it first eats the wasp egg and then the host before pupating and emerging as an adult velvet ant. Other than that, it’s known that the females are flightless while the males are winged, and the females pack an impressive sting, to the point where they’re also called “cow-killers” or “mule-droppers”.

Dasymutilla klugii

Obviously, I wasn’t insane enough to test the stories, because I tend to pay attention to warnings along the lines of “much more painful than a bee sting”. I settled for watching it scramble through the sapling, desperately looking for something that it couldn’t quite find, before leaving it to go about its business.

And how was this an old friend/enemy? Being a kid of the northern US, my views on Texas were based on reading, particularly a copy of the book Poisonous Dwellers of the Desert by Natt N. Dodge that had been left at my house by a friend when I was nine. By the time I was thirteen, I had read that book to death, regaling everyone with horror tales of cone-nosed bugs, puss caterpillars, the multiple species of scorpion and dangerously venomous spiders to be found in the Chihuahuan and Sonoran Deserts. After I informed a honeybee-stung neighbor that scraping out the sting is much better than pulling it out, she asked me how I knew this, and I merely pointed to the paragraph in question. At that point, nobody in the family questioned me about the arthropodal horrors we’d encounter in North Texas, even after my mother was playing solitaire on the floor of our new living room in Flowermound and put down the 10 of hearts atop a bark scorpion that was checking out the neighborhood. (Two days later, she found another in a huge crock bowl she used for making popcorn. That one became the basis for my first experiment in encasing a scorpion in epoxy, but that’s another story.)

Anyway, the summer of 1980 not only brought us the hottest summer in North Texas history, only possibly exceeded by the droughts of record of 1952 and 2011, but it brought out all sorts of critters. At the time, I lived on the edge of a huge subdivision that was under construction through the year, and honed my then barely existent tracking skills by chasing down the multitude of new animals that I’d never before encountered. One of these was a similar ball of fluff, and I knew well enough about not letting it sting. What I didn’t know is that velvet ants also bite. HARD. I yelled and flung it as far away as I could before it could reacquire a stinging target, and that was the last velvet ant I would see for nearly one-third of a century. And so it goes.

Tales From The Ranch: Spot the Horsecrippler

As mentioned several months back, I’ve become extremely fond of the West Texas barrel cactus Echinocactus texensis. It’s not impressive, like many other species of barrel cactus. In fact, the reason why one of its common names is “horsecrippler” is that between blending into the local soil and growing in areas with lots of grassy cover, only two circumstances allow most people or animals to see one before they step on it. If the cactus isn’t blooming or bearing fruit, they’re nearly impossible to see without a very careful view of the locale.

Don’t believe me? Let’s play the latest Triffid Ranch game, “Spot the Horsecrippler”. Within the photo below are fourE. texensis in plain sight. Can you spot them? (I’ll even give a hint: two are directly in the center of the photo, one is up and to the right, while the last is over on the upper left.)

Spot the Horsecrippler Cactus 1

Okay, to be fair, we’re looking at a smaller photo, with standard Web-ready resolution. Let’s go for a much closer view. Spot any of them now?

Spot the Horsecrippler Cactus 2

If you didn’t spot any, congratulations. You now see why these cactus can be dangerous to humans and animals. If you did, I know a few red-tailed hawks who want to steal your eyes and use them for themselves. The problem isn’t just that horsecripplers are down low. It’s that they flatten out over the ground, and with a bit of grass and some faded flower blooms, they’re almost invisible.

Spot the Horsecrippler Cactus 3

As mentioned before, at two times of the year is E. texensis easily visible, and for the same reasons. The blooms are gigantic compared to the cactus’s diameter, all the better for bees and other pollinators to see. The other time is when the fruit ripens, so it catches the eye of birds and other-color-seeking herbivores. Between the color and the scent, the fruit attracts everything from lizards to mice to pigs, and the seeds (roughly the size and consistency of buckshot) either scatter as the fruit is eaten or in the diner’s feces. Either way, after the fruit is gone, the cactus goes back to complete, welcome obscurity.

Spot the Horsecrippler Cactus 4

This isn’t to say that all E. texensis are, and forgive the pun, wallflowers. Occasionally, one comes across mutants with attention issues, growing well above the height of their neighbors. In garden and container environments, where nutrients and water are much more available than in the wild, horsecripplers will grow much larger and rounder, but not necessarily taller. This one is definitely E. texensis, based on the spine pattern and shape, but it may be interesting to see what happens with subsequent generations over the next few centuries. (Considering how slowly horsecripplers grow, this will have to be a multigenerational effort. Most of the cactus in these photos are at least 40 to 50 years old, and many out on the ranch may be two centuries old. Time for more research.)

Spot the Horsecrippler Cactus 5

All of this leads to speculation with, to paraphrase Joe Bob Briggs, absolutely no facts to get in the way of the story. Most smaller cactus species go for either cryptic coloration or impressive spines, and rarely do they go with both. If anything, most barrel cactus species herald their spines to encourage animals to walk and seek food elsewhere. Horsecripplers not only flatten out, but they also put down an impressive taproot to keep them anchored, and nothing alive today other than humans has the determination and the apparatus necessary to pull one out of the ground to eat it. What I wonder is if some form of the Pleistocene megafauna that used to wander this area during the last big glaciation had a taste for horsecrippler ancestors, deliberately seeking them out in grassland and pulling them up. If this was something that both had the time to dig up the cactus and had strong enough claws to scrape out the hard soil underneath, it explains why horsecripplers have such strong spines. Horses and cattle wouldn’t waste their time trying to chew on one, but what about ground sloths and glyptodonts?

Ah, now there’s an image you weren’t expecting to get from a gardening blog, were you? Naturally, this is all pure speculation based on E. texensis structure, and it can’t be proved without examples of glyptodont scat that show bits of chewed-up horsecrippler. The image, though, sticks. Texas gardeners already have enough of a problem with nine-banded armadillos digging up lawns and flowerbeds in the night in search of grubs and insects. Now just picture a vegetarian armadillo the size of a Volkswagen Beetle, galumphing into your back yard in a mad search for native cactus. Just remember: you have to sleep sometime.