Ant-Mimic Jumping Spider
While coming up the hill on my way home from work[1], I spotted what looked, at first, like a medium-sized ant. It didn’t look quite right, though, so I caught it and brought it home. It turned out to be this:
Archive for the ‘Arachnids’ Category.
Female Crab Spider
Back in November, I posted pictures of a male crab spider, today we have some pictures of a female, for contrast. She probably isn’t exactly the same species, but she’s fairly close.
Elongated Running Crab Spider
I’d like to say right now that, if you want to get pictures of all the bugs in your house, you really can’t beat having a 2-3 year old child helping you find them. Sam found this spider on the rug just a couple of weeks ago (in January)[*], and brought it to me alive and undamaged. It even has all of its legs for once!
Cobweb spiders
This is a species of spider that has successfully colonized the dark corners of our house: so far S_ found me three specimens to photograph in December and January (two females and a male). I could tell that one of them was male because he had enormously swollen pedipalps, which I understand means he was ready to mate. He was within a few inches of one of the females, so we suspect that he was courting her when he was caught.
Male funnel-web spider
Kitchen linoleum is a great place to find spiders - they stand out so well, particularly on light-colored floors, and usually they are far enough away from cover that catching them is a snap[1]. This fellow was scurrying across the floor, and once I caught him, he kind of scrunched up with his legs pulled in:
Male Goldenrod Crab Spider
This crab spider was on the kitchen counter on July 5[1], strolling along just as bold as you please.
It appears to be a male goldenrod crab spider, Misumena vatia.
Varroa mite
I hate these soooo much . . .
This is one that, as a hobbyist beekeeper, I am all too familiar with:
This is a varroa mite, Varroa destructor[1]. They are a parasite of honey bees, derived from a parasite of the asiatic honey bee Apis cerana. The asiatic honey bee has established a stable host/parasite relationship with their strain of varroa mites, so the mites don’t wipe out their colonies. Unfortunately, the western honey bee Apis mellifera, the one that most of modern beekeeping is based on, has not established such a relationship, and if left alone these mites will wipe out a normal western honey bee colony within 1-3 years, depending on the climate. These mites got into North America (probably on imported bees, but nobody is quite sure when or where), in the early 1980s, and have come close to wiping out both commercial and hobbyist beekeeping in the US several times since then.
Jumping Spider
Little Brown Job
When birdwatching, there are a lot of what S. calls “little brown jobs”, little nondescript brown birds (sparrows and the like) that an amateur doesn’t have a prayer of identifying on-the-fly. Well, there is the same problem with jumping spiders, like this one:
This is in the family Salticidae, which is a huge group of arachnid “little brown jobs” (about 4,400 species identified). There are at least two species around here (brown ones like this one, and black ones with white stripes that I hope to get a picture of later). Whether this is just two species, or two groups of umpteen species each, I don’t know.
These little guys don’t build webs, instead they charge around pouncing on things. As you can see in the next picture, they have really good eyes for a spider:
Isn’t that a sweet face?[1] They are believed to have full binocular vision (depth perception is so important when you are planning on pouncing on something), and they can jump a couple of inches. This particular one sat for the photos, and then abruptly leapt completely out of the dish and scurried off. They’re kind of like the ant lions in that they either don’t move at all, or move so quickly that they almost seem to teleport from point to point.
Wood Ticks
Well, once again, it’s Tick Time. They hang out on tall objects (mostly dead weed stems and the sides of buildings) with their little front legs outstreched, and grab on when someone brushes past unsuspectingly. They don’t bite right away, so we usually find them when they are still crawling around looking for a place to latch on (at this time of year, every little tickle and itch becomes suspect). The ones we have around here are good old Dermacentor variabilis, which some people call a “dog tick” and others call a “wood tick”, while just about everybody calls it an “eeewwww” when they find it crawling up their leg.
House Pseudoscorpion
What timing! I’d just gotten the camera mounted to take nice, high-magnification photos of tiny things, and then S. tells me there is a pseudoscorpion in the bathtub, just *begging* to be photographed. So, here it is:
Then, we flipped it over to have a look at the underside:
And then, finally, zoomed in on one claw:
Considering that this little guy was only about 3 mm long, I think the photos came out pretty sharp. We figured that this should be good enough to get a full, positive ID, so I found an identification key to the pseudoscorpions of Michigan in the MTU library[1] . . . and had my illusions pretty much dashed. It turns out that you distinguish pseudoscorpion species from each other based on very fine details of the claws, and where exactly the sensory hairs (setae) are located. Unfortunately, even though the claw detail photo is pretty good, it isn’t good enough to count setae. According to the author of the ID key, even an expert might take as much as a week to prepare, dissect, and examine a pseudoscorpion to determine the species. There are supposed to be at least 29 species in Michigan, so the next ones we find might get taken in to the lab for a more thorough examination.
While a really positive ID isn’t practical from these photos, the fact that it was in the house (and, specifically, in the tub) means it was almost certainly Chelifer cancroides, also known as the “house pseudoscorpion” or “book scorpion”. This is a “cosmopolitan” species, meaning that we have carried it around the world and it pretty much lives everywhere that humans live. They are actually very common, but are rarely seen except when they, say, venture into the bathtub to get water. They spend the rest of their time eating other, even smaller arthropods (mites, clothes moth larvae, and the like), and generally get dismissed as being harmless and of no economic impact. They are reported to live for 2-3 years, which is pretty good for such tiny creatures.