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Jun 10, 2018 19 tweets 6 min read Twitter logo Read on Twitter
For this week's #DeepDive, let's talk about the Southern Flannel Moth!

It's not well known, although we get lots of pictures of these guys.

Severe outbreaks can cause schools to be cancelled, so this is a very weird and important venomous caterpillar.
I am aware of three major outbreaks of these guys, although I'm certain there are others which have escaped my attention.

All three happened in Texas, one in 1913 and 1920 closed schools until the caterpillars could be sprayed. A third, in 1958 resulted in thousands of stings.
These guys like to feed in elm and oak trees, popular landscaping plants, and will fall off when disturbed by a bird or a parasitic wasp.

Most encounters happen when they land on someone (like inside a shirt) or while they're looking for places to pupate.
Unlike spiders, flannel moth (asp, Trump Hair, etc) caterpillar stings can be easily recognized by the gridlike pattern of their stings.

Under that crazy hairdo, they have regularly spaced stingers that break off and let venom leak into the skin.
So...why would a caterpillar need to be venomous?

It's all about protection. If something tries to grab them, they can deliver a quick and extremely painful sting...allowing them time to drop off the plant and hide 20 ft down.

(Note: Not a Flannel Moth Caterpillar)
The picture above isn't a flannel moth caterpillar...instead, it's a Saddleback caterpillar which is another venomous species.

Unfortunately, I don't have any great action shots of Flannel Moth caterpillars stinging and this species is better because the stingers aren't obscured
In general, venom in caterpillars is pretty rare. There's only about 30 species in 10 families that are venomous. However, they're spread pretty far and wide.

Their venom isn't very well researched, either.
Megalopyge venom is pretty much unknown. We *think* it's a protein which chews up other proteins, but it's pretty much uncharacterized.

If you think about it, that's crazy. There's a caterpillar which can be an epidemic, and we don't know how it makes people sick!
While we don't know a lot about the venom of the Southern Flannel moth, we know a lot more about the venom of the caterpillar below.

See...flannel moth venom is very painful.

The caterpillar below is Lonomia obliqua...and it's famous because it's venom can kill people.
Lonomia venom isn't particularly toxic (it's about 1/10x less toxic than black widow venom), and deaths are somewhat rare (2.5% of stings).

However when stings are bad, they're *really bad*.
The venom of Lonomia is actually very interesting. Two species can cause fatalities, and the venom of each species acts in very different ways.

The venom of both lethal species acts on the blood clotting cascade, and throws it out of whack.

Death is caused by brain bleeds.
While we can't go through *every* venom protein here on Twitter, we can discuss the main component.

The main component of Lonomia venom is called Lopap, and it acts like a switch that flips on the enzyme which forms the actual blood clots., here's the weird thing. People stung by this caterpillar don't die from strokes.

They die from *bleeding*

...but this protein causes blood to clot.

Why would it cause bleeding?
Again, we can only give a simplified version here...due to the complexity of the clotting cascade and the interaction of the different venom components.

However it seems that Lopap is so efficient that it depletes the supply of Fibrinogen...which eventually causes massive bleeds
So...this seems like it would have some medicinal properties, if the effects could be controlled and localized.

However, *a lot* more research needs to be done before it gets to that point.
So...all in all, there are venomous caterpillars which have outbreaks that can cause disruption in people's every day lives. In South America, there are even caterpillars which can kill people.

Despite their medical and cultural significance...we know nearly nothing about them!
Side note 1: If you want to read up more on Lonomia venom, here's a very thorough (but not very accessible) review:

Carrijo-Carvalho, L. C., & Chudzinski-Tavassi, A. M. (2007). The venom of the Lonomia caterpillar: an overview. Toxicon, 49(6), 741-757.
Side note 2: If you want to see what the adults look like or if they're found in your area, you can find that information at the @BugGuidenet link below:
Side note 3: @kmagnacca was super awesome and reminded me of a paper I read, but opted not to cite because it covered the death of someone stung by Lonomia...and it has pictures.

However, that paper (cited below) also has a figure which shows the other Lonomia venom proteins!

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More from @BugQuestions

Aug 26, 2018
Yeah, we get pictures/videos of this occasionally.

Ants don't really do 'funerals'; even the dead in their own colonies are put into a garbage dump rather unceremoniously.

There's a handful of possibilities for this behavior...
1.) They may be attempting to bury it, especially if it's on a hard surface.

Lots of ants bury large food items to protect it from scavengers, other ants, and to absorb liquid which comes out from the prey.
2.) The critter happened to fall into the colony's trash pile.

Ants put waste (dead ants, poop, shedskins, etc) into a large pile called a 'midden pile' which functions just like our landfills.

If something ended up in that pile, they could be moving stuff out of the way.
Read 4 tweets
Aug 25, 2018
I think this problem hits at the heart of the issue when it comes to Eckbom's, because it's often not about infestations.

This deserves it's own thread to describe how complicated this problem is, and how poorly understood it is.
So...first, I believe that these people are accurately describing their perceptions of medical issues.

Urban IPM Extension people can go through samples to find insects, inspect homes for infestations (bed bugs, fleas, etc), get someone to do skin scrapings for Scabies, etc.
However, after that, they need to be passed onto a doctor.

Often times, attempts at self-treatment can cause skin irritation. Pesticide poisoning can also cause crawling sensations.

Brain tumors, autoimmune diseases, even cold weather can do this as well.
Read 4 tweets
Aug 25, 2018
Scientists make their living using their brains to interpret data.

So what happens when that organ breaks, and a respected researcher becomes mentally ill?

In this week's second #DeepDive, let's explore the case of Jay Traver.

CW: Mental illness
Jay Traver was one of the early entomological pioneers. Her career centered mainly around aquatic insects, specifically mayflies.

Most of her work-which is still cited to this day-revolved around describing the lifecycles of mayflies.
In 1951, Traver published a paper where she claimed to have experienced an infestation by a mite called Dermatophagoides scheremetewskyi.

This is a mite which lives in homes, and although it causes allergic reactions, it was known at the time to not be parasitic.
Read 15 tweets
Aug 24, 2018
A new meme going around FB claims the WoodLouse Spider is a "deadly new species" wrecking havoc in the Southern US

It's a completely harmless spider, but it still has a neat story to tell.

For the first of this week's two #DeepDives, let's explore the biology of Dysdera crocata
So, for the first tweet in this series, let's put these rumors to rest with data.

There's a lot of verified bites from D. crocata in the medical literature-which is rare. One person allowed themselves to be purposely bitten multiple times.

No deaths; everyone was just fine.
D. crocata gets it's name-the woodlouse spider-from it's food.

They live in dark, moist, areas and are adapted to feeding on sow bugs...sometimes called rollie-pollies.

They use those huge mandibles to foil the isopod's defensive rolling.

Read 8 tweets
Aug 21, 2018
It is with a heavy heart that we announce that one of our colleagues, Vazrick Nazari, has been arrested for possession of child pornography.

We cannot tolerate exposing our followers to this sort of person, and have blocked him from our feed.…
We did consult him for help with moth IDs here on Twitter, and although there's no way we could have known he was doing this, we still feel the need to apologize for exposing our readers to-and let's just put it as bluntly as possible-an alleged child predator.
We try to be careful about who we consult, and let into our conversations.

Unfortunately, it's not always possible to know what's going on behind the scenes.

Needless to say, we will not be requesting any more assistance from this person.
Read 4 tweets
Aug 18, 2018
With Glyphosate being in the news due to a recent court ruling, let's take this opportunity to explore the history of pest control in this week's #DeepDive.

It's a huge and complex topic, so the best we can do is a brief overview.
It's not really known when humans started using pesticides.

The first agricultural societies began about 10,000 BCE, with several independent shifts around the world from relatively nomadic lifestyles to those tending crops.
The first records of pesticides being used is in Sumeria, where they used elemental sulfur to control crop pests.

This is largely an accident of geography; Sulfur deposits are abundant in a stretch between Mosul and Fatha...which allowed easy access.
Read 27 tweets

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