Latrodectus umbukwane is a breath-takingly gorgeous spider from South Africa. Look at those colors!

As you might guess from the genus, it’s related to black widows, which means of course everyone gets worked up about its potential venomous nature. It hasn’t bitten anyone that we know of! Get over it! It seems to be, if anything, unusually shy.

Also, you want to see some sexual dimorphism? Take a look at this.

Well, this is a stupid sensationalist headline: New Species of Spider Found in Mexico Able to Rot Human Flesh. Yeah, so? This is a common property of many venoms, such as those in some wasps and snakes, and it makes sense that a spider, which relies on injecting toxins and enzymes that break down cells and tissues, would do so. How else would they slurp out the digested guts of their prey? These spiders have no interest in eating people, or “rotting human flesh”, so it’s an obnoxious way to distort the story.

I can just imagine spider tabloids running stories title “New Species of Primate Found With Large Fleshy Butts Capable of Crushing Innocent Spiders”. It completely misses the story.

Here’s a pic of the lovely beast in question.

It’s called Loxosceles tenochtitlan, and it’s distinguishing characteristic is not that it has a remarkable venom, but that males and females have unique genitals in a lock-and-key arrangement, which is also common in invertebrates.

In a statement released by the university, Valdez-Mondragon explained the difference: “As L.tenochtitlan is morphologically similar to L.misteca, it was initially thought that it had been introduced to this region by the shipping of ornamental plants. But when doing molecular biology studies of both species, we realized that they are different.” Valdez-Mondragon described the species and noted the difference between L.tenochtitlan and L.misteca lies in the male spider’s palp or the organ that enables touch in arachnids. It is also noted that the female L.tenochtitlan has a distinct looking sexual organ compared to L.misteca. Valdez-Mondragon explains that at first glance, the two species of spiders can look identical, but L.tenochtitlan can be identified because of its dark brown color which is dull compared to the other species and on its back is a very visible violin pattern.

The story goes on to claim that “humans are naturally repulsed at the sight of “creepy crawlies” like spiders.”

The Science Times is not one of my approved popular science sites. Too much trash written by people who have only the most passing acquaintance with science.

I have been neglecting my spiders this week — every day I get a little time with them, and then I realize I have to get grading done, and then I have to regretfully leave the lab to hunch over papers again. It’s unfortunate, too, because this is the week I’ve been trying to get them to breed, and there’s courtship to watch.

A little background: last year I had limited success with breeding because I was raising all the spiders in these 3cm diameter tubes, which is convenient and allows me to pack a lot of spiders into an incubator. The catch was that mating was fraught; put a male in a tube with a female and it was going to end in violence and cannibalism more often than not. Imagine that you wanted to study human courtship and mating, and your strategy was to keep women in those little capsule hotels, with plenty of food and water, and then every once in a while you picked some random guy and stuffed him into a capsule with a random woman, and then you planted a camera in the window to watch the fun. At best you’re going to see a strange and unrealistic version of mating…at worst, violence and death. Maybe cannibalism if you’re really lucky.

This year, I’m raising females in spacious cages where they can build large webs, and where there’s space to scamper off and be alone. I’m introducing males to these female-dominated spaces, and…well, so far it’s been less than exciting. It’s more like watching a junior high school dance. There’s a girl, hanging out over by the wall. Boy comes in to the gym, they notice each other, they look warily at one another. Their body language all says “I see you”, but they’re so nervous that you can’t tell whether they’re happy to see each other, or they’re threatening to vomit all over their shoes if they get too close.

The boy works up his nerve and approaches cautiously, sending as many friendly signals as he can. In spiders, this involves web plucking; they send vibrations down the web to each other. “Pluck pluck pluck?” he says. She fretfully replies “Pluck pluck pluckity pluck.” Is this promising? The boy is uncertain. “Pluck pluck,” he says, and reaches out with one arm, tentatively. “PLUCK!” she screams, and charges. Boy runs away. “Pluck pluck pluckin’ pluck pluck,” she hisses, in her position near the punch.

At least, that’s how I interpret this one encounter I watched.

We start out with the male spider center right; he’s advancing towards the female, top left, just out of view at first. He’s been plucking up a storm just before the clip, and both are slightly agitated. He reaches out to her and…devastating rebuff. He flees. She settles down, but continues to pluck at the web…sort of angrily, if I anthropomorphize. When he begins to approach again (off screen), she rushes out to chase him away.

I left the two of them alone after that. There was enough space in the cage that they could separate safely, and he was quick to run away, so she’d have to be strongly determined to kill and eat him to pursue, and I’d put plenty of fruit flies in the cage beforehand, so she wouldn’t be that hungry. I came back the next morning (it was like a junior high dance with a lock-in, and no chaperones!) and rescued the male, who was hovering maybe 6cm away, body oriented to the female and looking attentive. I have no idea if mating was accomplished.

That’s been my week. Introduce potential breeding pairs, watch a little angsty teen dating drama, scurry away to grade papers, come back to find two spiders staring at each other, giving no hint about what they’d been up to.

“How was your date, son?” “It was alright, I guess,” he replies, sullenly.

“How was your date, daughter?” She screeches angrily in spider. I don’t know what that means.

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Good news! The male was left overnight with New Arya, one of my females who has built a cozy little nest with scraps of debris. When I just checked on them, the male was right outside the nest, tapping. New Arya was reaching out and waving at him. I decided to just leave him there a little longer and see what develops.

Also, Texanne of the triangulosa clan had made another egg sac. That’s three for her.

Which is why we found her lurking under our dining room table, where it’s cozy and warm.

Do you know who is living under your furniture and behind your cabinets?

You know, you have to love the look of joy on their faces when they open a surprise box. I imagine it would be like the Australians who opened a box intended for nesting opossums and saw this:

I know I’d be excited. Wouldn’t you?

Unfortunately, there’s a shortage of Huntsman spiders here in Minnesota. We’ve got lots of Pholcus, though. I’m thinking of going down into the basement and scooping up a swarm of cellar spiders, putting them in a gift-wrapped box with a ribbon, and mailing them off to the grandkids.

How can they not be delighted?

I have not been advertising this aspect of my research, but I have been striving towards developing a Perfectly Spherical Spider. Here’s my first success.

What good is a spherical spider, you might ask. The benefits are legion. For one, think of their utility in physics problems.

Actually, what happened is that I’ve started trying to breed the spiders with my impoverished bunch of small, young males, and because I was concerned about preventing nuptial cannibalism, I gave the lovely females a big banquet on their wedding night, and boy did they eat. It may have worked against me, because a) this female hasn’t budged in a couple of days, and I don’t think she can move, and b) the male I put in her cage gave every appearance of being fascinated and terrified, and orbited her at a distance of 5-10 cm. I’m hoping he might have darted in at some point over the weekend and done the deed, but who knows? I’ve pulled him out now and will place him with a possibly less intimidating female.

Isn’t she lovely, though?

Physicists: they make silken draglines, you could probably use spherical spiders in pendulum problems, too. You can’t do that with spherical cows!

Mary and I went on a spider safari. In our house. It started out fine; we didn’t find much in the living spaces of our home, but then we decided to dive down into…the basement.

We found MONSTERS!

Oh, wait. That’s just one thing from my son’s old Dungeons & Dragons collection. What we actually found was Pholcus. Pholcus everywhere. We took a few photos before fleeing.

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