#acariformes — Public Fediverse posts

#Mites of the #Astigmata (#Sarcoptiformes, #Acariformes), such as #Histiostomatidae shown here, practice #direct #spermtransfer via #copulatoryorgans in #males and #females. An #evolutionary #innovation derived from #spermatophoretransfer without copulation in #Oribatidmites. Advantage: a huge egg can develop and new sperm can be stored simultaneously.
©#StefanFWirth, July 2026

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#SEM #photos
©S.F.Wirth: #Histiostoma #palustre, H. sp, #aedeagus

The triumphant return of #MiteMonday!

Spotted this unusually reddish penthaleid mite on a decaying tree stump. Note the small pale #DorsalAnus on its back towards the rear of the abdomen.

#bugstodon #Mitestodon #mites #Acari #Acariformes #Penthaleidae

Still the depths of winter here. I have been having dreams about bugs. I recently had a dream about finding plump whirligig mites everywhere: some their usual orange-red, others greenish because they had just eaten something green…I miss the mites.

Here are some whirligig mites I found a couple of years ago on a rock down by the lake, fighting over a dead midge. #iNaturalist observation: https://www.inaturalist.org/observations/225382565 :inaturalist:

#MiteMonday #Mitestodon #arachnids #mites #Acariformes #Anystidae

#Mouthparts in #mites of the #Acariformes are usually normal shaped as typical for #arachnids. The #chelicerae are the feeding organs consisting of digitus fixus and d. mobilis. #Pedipalps have sensing functions with different kinds of #sensoryorgans. In #Histiostomatidae (#Astigmata) the whole #gnathosoma is modified into a complex #filterfeeding organ that creates an #underpressure on #food surfaces.
© #StefanFWirth Berlin 2026

Reference
S. F. Wirth (2023)
https://www.fao.org/fileadmin/user_upload/GSP/GSOIL4N/GSOIL4N-Posters/ID_167.pdf

Been a long time since I posted anything for #MiteMonday, but I was going through my camera and found this one I don't think I've shared before! Just a good old _Allothrombium_ red velvet mite.

#Mitestodon #arachnids #mites #Acari #Acariformes #Prostigmata #Trombidiidae

It's another #Arachtober #MiteMonday! Here's a whirligig mite (family Anystidae) cleaning its feet. Warning: handheld video! I was able to stabilize it a bit but the camera still moves around.

#ArthroBeauty #DailyMiteVid #Mitestodon #mites #Acari #Acariformes #Prostigmata #Anystidae

#Arachtober #MiteMonday: just a good old red velvet mite (_Allothrombium_).

Just imagine having a guinea pig-sized one, as a pet. It would be soft and squishy. It would enjoy squeezing into little crevices to nap. You could brush it, very gently. It wouldn't see very well. It could climb up things with little retractable claws. You could probably feed it mealworms.

#ArthroBeauty #arachnids #mites #Acari #Acariformes #Prostigmata #Parasitengona #Trombidiidae

#MiteMonday: ever look down and see a bunch of little red guys on the pavement or whatever? Chances are they're long-legged velvet mites (family Erythraeidae) in the genus _Balaustium_. Practically all of their relatives are parasitic on other arthropods as larvae and predatory as adults, but some common _Balaustium_ species are lifelong pollen-eaters. Here's one eating peony pollen I put down.

#DailyMiteVid #Mitestodon #arachnids #mites #Acari #Acariformes #Parasitengona #Erythraeidae

For #MiteMonday: mites eating things.

1. Long-legged velvet mites (family Erythraeidae, probably _Balaustium_) eating a midge
2. A whirligig mite (family Anystidae) eating a globular springtail
3. A snout mite (family Bdellidae) eating a barklouse

#DailyMitePic #Mitestodon #arachnids #mites #Acariformes #Prostigmata #Erythraeidae #Anystidae #Bdellidae

Bonus #MiteMonday: a _Balaustium_ sidewalk mite feeding on pollen from a horse-chestnut flower (which I put down to attract them and get photos).

These mites can be found in great numbers this time of year, very visible on surfaces like concrete and bricks, hence the name. As well as pollen and sap I've seen them feeding on dead bugs. Some are purely raspberry-red, others have this longer white coat or just white patches, others have a gorgeous blue-green iridescent sheen.

The pair of red protuberances are not eyes but special structures called urnulae, which secrete various useful substances like a defensive chemical/alarm pheromone, and a "waterproofing" compound that prevents their cuticle from drying out (useful as they spend a lot of time running around in the sun).

#DailyMitePic #Mitestodon #arachnids #mites #Acariformes #Erythraeidae

It's still #MiteMonday somewhere…

Vignette from under a log. A snout mite (family Bdellidae) feeds on the remains of a springtail, with a guest appearance from a beetle mite (order? suborder? Oribatida)*.

* Above superfamily or so, mite taxonomic ranks start getting contentious.

#DailyMiteVid #Mitestodon #arachnids #mites #Acariformes #Bdellidae #Oribatida

Belated #MiteMonday: it's the time of year I start carrying a little water dropper bottle for the whirligig mites. I've found it's a reliable way to get them to stay still for photos. 💧

#DailyMitePic #Mitestodon #arachnids #mites #Acari #Acariformes #Prostigmata #Anystidae

#MiteMonday: this weekend I got out to my sumo mite (_Allothrombium_) tree to catch some wrestling bouts!

It is some kind of sexual competition thing: certain males seem to stake out a little patch and aggressively defend it against all comers. The females, I think, are the larger ones who take little notice of the fights and mostly wedge themselves into crevices in bark? Courtship rituals seem to involve leg-tapping and walking around each other in circles. I am wildly curious about what's actually going on.

#DailyMitePic #Mitestodon #arachnids #mites #RedVelvetMites #SumoMites #Acari #Acariformes #Prostigmata #Trombidiidae

#MiteMonday: a red velvet mite (_Allothrombium_) sneakily snacks on midges from a spider's web. I also saw a red-winged blackbird eating a midge-filled spiderweb, too. At this time of year, the few spiders that overwintered catch so many midges that their webs almost collapse under the weight—more than they could possibly eat. I wonder how much midge biomass these spiders inadvertently make available to other animals!

#DailyMitePic #Mitestodon #arachnids #mites #RedVelvetMites #arachnids #mites #Acari #Acariformes #Prostigmata #Trombidiidae

#MiteMonday: it's that time of year again! A sheet-web weaver's web in a willow tree crevice is carpeted with tiny _Bryobia_ clover mites.

#DailyMitePic #Mitestodon #arachnids #mites #Acariformes #Prostigmata #Tetranychidae #Bryobiinae

I almost forgot it was #MiteMonday! Inspired by @zorbama's shot of a running crab spider, clover mite, and midge all together (https://veganism.social/@zorbama/114373000260983349), here's a running crab spider (_Philodromus_) I found feeding on a clover mite (_Bryobia_). I don't actually often find many arthropods feeding on the adults, though I've seen predatory _Anystis_ mites eating the eggs.

#DailyMitePic #Mitestodon #mites #DailySpiderPic #SpidersOfMastodon #spiders #Acari #Acariformes #Tetranychidae #Bryobiinae #Araneae #Philodromidae

#MiteMonday: wintertime rock flipping turned up some penthaleids and those iridescent purple springtails, not quite sure what they are. They were about the same size (see third photo).

#DailyMitePic #Mitestodon #arachnids #mites #Acari #Acariformes #Penthaleidae #springtails #Collembola

#MiteMonday × #LichenSubscribe: we got some flurries today, but at a few degrees above zero the clover mites (_Bryobia_) are still out and about. Here's one climbing over a tiny crumb of lichen.

#DailyMitePic #Mitestodon #arachnids #mites #CloverMites • #Acari #Acariformes #Tetranychidae #Bryobiinae

I can't even wait for #MiteMonday, this is too exciting, I have to share it now!!!

In Walter & Proctor's _Mites: Ecology, Evolution and Behaviour: Life at a Microscale_, there's this great image of mites in the family Acaridae mating, with the male facing backwards and his aedeagus (dick) inserted into the female's dorsal copulatory opening (bussy [back pussy]), so he is carried along on her back, a bit like a wheelbarrow race, but backwards.

Anyway this evening I was idly taking macro of the mites in the fruit fly culture when I SAW IT. It's easier to make out with video.

marked nsfw for graphic photos and videos of mite sex, you were warned

#Mitestodon #DailyMiteVid #arachnids #mites #MiteBehaviour • #Acari #Acariformes #Acaridae

#MiteMonday: Astig explosion!!!

I had been putting off making a new tub of fruit fly medium and excelsior for the flightless fruit flies, and discovered the other day that the current tub had quite the population of astigmatid mites, feeding off the same stuff and emerging in great numbers to swarm the outside of the tub during the warmest part of the day. I was actually pretty excited about this, as I hadn't personally seen an infestation of these since childhood, long before I started doing smartphone macrophotography (as a matter of fact, long before smartphones existed, but anyway…), and posts about them on bug ID forums are, for some reason, virtually always low-res shaky videos. So I actually had a chance to get up-close photos!

Astigs, which branched off from oribatids, are a large and diverse group. Some common species, largely in the family Acaridae (like _Acarus siro_ and _Tyrophagus putrescentiae_), are found around the world as pests of stored products. They may be called "grain mites", "mold mites", "flour mites", "cheese mites", etc. They are harmless, though in huge numbers (e.g. in a bakery, barn, or grain silo) they can spoil food.

I had just been using a pantyhose sock thing to cover the fruit fly tub, but I went out and got surgical masks so I can make something less porous. I'll also make a fresh batch of fruit fly medium and toss the old tub. That should help keep the mites at a more manageable level.

I can't ID these precisely—you really need an expert with a key and a microscope—but they're likely Acaridae of some kind.

#DailyMitePic #Mitestodon #arachnids #mites • #Acari #Acariformes #Acaridae

#Arachtober 28: the last #MiteMonday of Arachtober! On a rock teeming with clover mites I found several of their frequent predators, whirligig mites (family Anystidae). This one was busy cleaning its feet.

#DailyMiteVid #Mitestodon #arachnids #mites • #Acari #Acariformes #Anystidae

#Arachtober 21: Happy #MiteMonday! Here's a snout mite (family Bdellidae) snacking on a long-legged velvet mite (family Erythraeidae). Taken back in June.

#DailyMitePic #Mitestodon #arachnids #mites • #Acari #Acariformes #Prostigmata #Bdellidae #Erythraeidae