Missouri Master Naturalists- Springfield Plateau Chapter

Thursday, August 27, 2020

Scoliid Wasp Week

Blue-winged Scoliid Wasp - Patty Hatcher

Patty Hatcher posted this picture of a blue-winged scoliid wasp on our MN Photos page.  This is Scolia dubia which in this case can be differentiated from the other other Scolia sp. because the yellow spots on segment 3 are sometimes very faint or absent.

I was preparing a blog on the double-banded scoliid wasp, Scolia bincincta which Ben Caruther's had photographed earlier in the month so this is our Scoliid Special.

 

The Scoliidae family of wasps has 20 species in the US.  According to UF Featured Creatures,

"The family Scoliidae is composed of fairly large, stout-bodied wasps, often brightly patterned in shades of red and yellow, white, or one of these colors in combination with black. These wasps are parasitoids of soil-inhabiting scarab beetle larvae. "

 

Scarab beetles are in a large family with 1400 species to choose from in the US, some of which are shown on this Bugguide link.  There are many common species including the May and June beetles, Hercules beetles, dung beetles and the never popular pesky Japanese beetles.

All have in common grubs that live underground until emerging, sometimes damaging lawns.  In their defense I would point out that they were here 270 million years before the invention of the lawnmower.

The female Scoliid wasp uses her special powers to locate the grub underground, find and sting it into a zombie-like state and lay her egg on it, leaving it buried.  The larva emerges from the egg, feeds on the immobile but living grub for two weeks and then forms its cocoon where it spends the winter.*  When the adult  wasps emerge they consume nectar and pollen, incidentally moving pollen from plant to plant. 

*The whole Scoliid life cycle is described in detail by Bug Eric.

Monday, August 24, 2020

Spider Wasp

Ben Caruthers was able to photograph this wasp and identify it as the Elegant Tarantula Hawk, Pepsis menechma.   Ben reports: 

"I have seen these flying through my yard all summer. They are very wary and difficult to photograph. I had to use my 600mm zoom to capture this one. Those yellow antennae are really eye-catching. I usually spook them from their hunting spot on the ground. I saw this one land and went to grab my camera. It hunts on the ground through the grass. It moves quickly and I never got to see it catch anything."

Like Spiderman, spider wasps have special powers.  They are able to track down and catch spiders including some like wolf spiders that are larger than they are.  They paralyze the spider and haul it off to a nest which they have appropriated from another animal. There they leave it as food for their young.  The adults stick to nectar for fuel, drinking Kool Aid while the kids eat.....Yuck!  You can see all this action in this video.

E. fulvicornis - Wikimedia

Discover Nature also discusses the spider wasp family, Pompilidae.  They mention identifying features found by stretching the hind leg out, something that sounds dangerous to me.  I will stick with photographs and live observation.

"The extra long, spiny hind legs that often dangle downward in flight, and the nervous flicking of the wings are helpful characters for identification at a glance. The spider-hunting behavior, often on the ground, is another strong clue."

There are over 5,000 species of spider wasps world wide.  The Godzilla of them all is the tarantula hawk which we discussed in this 2013 blog.  Schmidt in his now famous pain scale ranked it with the gusto of a food critic as the second worst sting.  We don't have any data on Ben's spider wasp and anxiously await his report on picking one up.

Friday, August 21, 2020

Ants in the Saddle - Part 2

Jean Parker posted several picture of a Dryad's saddle mushroom in her tree, shown in the last blog.  This and a few ants crawling it have made a story that requires two blogs for the telling.  Jean goes on to say, "I look closely and see ants busy taking pieces of it UP the tree. Probably penthouse spoils. They came down from the rotted knot in tree then went to right then up up and far away.   Wow, nature never ceases to amaze."

 

Most amazing is the little ants measuring 4-5mm are able to work as a coordinated team of 20+ to chew a piece of the fungus from the edge and then haul it up the tree!  It reminds us of the rubber tree in the song High Hopes.

I sent this photograph to James Trager who responded:

"This ant - Aphaenogaster tennesseensis - is omnivorous, though perhaps more predatory-carnivorous than most in its genus. I commonly see them on a variety of recently formed fungal fruiting bodies, and presume they are taking home bits to feed their larvae. I have not actually seen the larvae chewing on mushroom bits given to them by their older sisters, but I'll just bet if you could peer into the brood chamber after the adults bring this material home, that is what you would see."

To illustrate AT's carnivorous side, James sent along a photograph from the St. Louis area of the same species a few days later.  These ants were hauling in a millipede for supper.  This is the underside, a white and no doubt juicy teneral, having just emerged from its molted skin.  Ordinarily it would toughen and develop color over the next few days but this one may not live that long.  Meanwhile some were carrrying a piece of bark up the tree as seen in Jean's video.

Meanwhile, back at the fungus,  Antwiki says A. tennesseensis, "Nests may be in rotting stumps or logs, in standing dead trees, and in dead portions of live trees (Smith 1965). Mature colonies have several hundred to several thousand individuals (Smith 1965). The latter estimate would be unusually high for a species of eastern Aphaenogaster. Foraging is usually on the ground, where the workers collect small arthropods" 

Diving deeper, we hit pay dirt.   Food-webs posted research showing this is a common finding in Aphaenogster sp.

"Previous accounts of fungivory in ants outside these fungal-feeding specialists have been questioned due to whether or not ants consume fungal tissue or prey on mycophagous insect larvae present in or on mushrooms. Here we show that ants in the widespread genus Aphaenogaster recruit to mushroom baits in the field regardless of whether or not mushrooms contained insects upon which ants might prey. When dye-stained mushrooms were provided to colonies in the lab, ants fed on mushroom tissue and dye was visible throughout their digestive tract."

To quote our fellow naturalist Jean, "nature never ceases to amaze."

Thursday, August 20, 2020

#Ants in the Saddle -Part 1





Jean Parker posted several pictures of a Dryad' Saddle mushroom in her tree.  This and a few ants crawling on it have made a story that requires two blogs for the telling.  First Jean's story.

"I had a tree removal service come by to give me a quote to remove a big old silver maple. He showed me how it was rotting by stabbing in a hole with his pen to demonstrate how soft it was. Falling apart.

So....a week later I have a fungi! No doubt in protest to the stabbing. My Seek app says its a Dryad's Saddle. I want Mark proud of me!!  I look closely and see ants busy taking pieces of it UP the tree. Probably penthouse spoils. Wow nature never ceases to amaze."

Dryad's Saddle (Cerioporus squamosus) is a polypore bracket fungus which is well described in this MDC Discover Nature Field Guide.
"This species lives as a network of cells (mycelium) within living trees as a parasite, and dead trees as a saprobe, that digests and decomposes the wood. When ready to reproduce, the mycelium develops the bracket that emerges from the log—this is the reproductive structure. In polypores, spores are produced in the pores beneath and are released to begin new mycelia elsewhere."

This one grew out of a living tree.  In this case it is a parasite, attacking the heartwood of a weakened tree that is dying.  They are often found where branches have been sawed or broken off at the trunk as you see above

Dryads in Greek literature were wood nymphs, specifically the nymphs of oak  trees, though the term has come to be used for all tree nymphs in general.  The saddle shape of this mushroom was felt to be just the right size for a wood nymph.  The Greek gods punished any mortals who harmed trees without first giving gifts to the tree-nymphs.  The god's certainly resented the poking a pen into the tree!  What would be an appropriate gift for a tree god is Greek to me.

Dryad's Saddle-  Wikimedia
Like many other fungi, it is valuable in the woods, decomposing wood.  Just imagine what our woods would look like if fungi didn't start breaking down dead trees - dead tree trunks stacked hundreds of feet high?  This polypore especially likes elms but also works on maples, poplar, willow, beech and ash.
The body can be yellow to brown and has "squamules" or scales on its upper side. On the underside one can see the pores that are characteristic of the genus Polyporus; they are made up of tubes packed together closely. The tubes are between 1 and 12 mm long. The stalk is thick and short, up to 5 cm (2.0 in) long.  -Wikipedia 
Mark Bower

Andy Vernon- Wikimedia

 

 

 

 

 

 

Another common name is "pheasant back". 

The most intriguing part of this mushroom was its odor, a nearly perfect mimic of watermelon rind!  The fresh tender edges are considered edible and Maxine Stone in Mushrooms of Missouri describes a way to turn it in to a mimic of watermelon candy!

Coming next, Ants in the Saddle Part 2


Mushroom-collecting.com has pictures and cooking suggestions.  Never eat any mushroom unless you are absolutely sure of its identification.

Sunday, August 16, 2020

Butternut Woollyworm

 
Along our lane I came across a little walnut with badly chewed leaves and this on a petiole.  I found two others on the underside of leaf remnants, all immobile until I annoyed them.  This is a butternut woolyworm, Eriocampa juglandis.  It is a sawfly, the combined name signalling that it isn't really a "fly."  It is actually a member of the wasp family only with a thicker waist.
 
 
In a closeup side view you can make out the legs on the thorax.  The larva is covered with a white material thought to deter parasitoids and predators and it certainly isn't very appetizing to me. I could find white patches of fluff covering exuviae as they molted but it clings onto the larva unless scrapped away as you see in this video as I annoyed it into action.
 
BWW larva and exuviae

Walnut sphinx moth - Shelly Robertson
 
 
 
The BWW caterpillar-like larvae have a voracious appetite but are picky eaters, only feeding on walnut and hickory.  Walnuts produce a chemical called juglone that is allelopathic and inhibits a lot of competing plants in the vicinity.  It is also a natural insecticide, warding off predators.  Species like the BBW and walnut sphinx moth can detoxify juglone, converting it into a harmless chemical.
 
Sawflies have their own fan club.  Most species are picky eaters with specific plants they use.  They get the "saw" from the female's ovipositor used to insert eggs into the plant tissue.  There is a lot of variation in the organ and how deeply they plant the eggs.  The Bug Lady describes how they use their little saw and create their waxy disguise.


"Females saw into the mid-rib of leaflets and deposit 20 to 30 eggs, one at a time, which eventually causes the leaflet to droop or fold and the midrib to turn pale; and while small larvae chew random holes in leaves, larger ones may finish them off entirely, leaving bits of the larger veins behind.
 
Unadorned larvae hatch in about a week and commence producing waxy, white fronds to adorn themselves. Each molt leaves the feathery skin behind, and the larva must cloak itself anew. Finished growing, they drop to the soil. The pre-pupal larva forms a cocoon in which it overwinters in a state of suspended animation (aestivation), pupating in spring. The cycle is completed when adults emerge in early summer."

The next time you see white bird dropping on a leaf, look a little closer.

Saturday, August 15, 2020

Wren Housekeeping

Richard Locke posted this Youtube video of a wren feeding its chicks which finishes up with the scene above.  Check it out now as we will repeat the final scene below at length.  Then, if the last 5 seconds offend you, close this window.

As a reformed gastroenterologist this was too good an opportunity to pass up.  As you may have guessed by now, this isn't dinner for a chick but the remains of dinner past.  Many of the feeding trips the parents make end in hauling out the waste, the bird equivalent of changing disposable diapers.  Fortunately these are biodegradable disposables.  The very act of eating can stimulate the gut urge to empty.  This is called the gastrocolic reflex in humans and probably something worse in bird language.  If you are still with us, Audubon describes this more scientifically.

"Perhaps you’ve glimpsed the process before: A nestling turns its rear end to mom or dad and ejects a floppy white bag of poop encased in mucous: a fecal sac. The parent then flies away to dispose of it. Or scarfs it down as a snack.

Fecal sacs, which only nestlings produce, are common among passerines like robins, bluebirds, and other “altricial” birds (species that require around-the-clock parental care at birth).   According to Michael Murphy, a biologist at Portland State University and a fecal-sac expert, only a handful of studies have been done on the subject."

OK, maybe not pure science but you get the idea.  Fecal sacs are encased in mucus.  This requires protein which is a valuable resource.  Journey North  has a lot more detail on the sacs to describe the process.  Once the chicks fledge, they stop wasting protein on making the sac and poop freely anywhere they want.

Richard Louv describe the large numbers of caterpillars a chickadee feeds its young every day.  Imagine how deep a pile of feces would pile up in a nest over several days.  The parents hauling out the diapers serves multiple purposes.  The obvious one is hygiene, reducing the material that support bacteria.  Another unproven theory is that it prevents predators from finding the nest by its odor.


If you are still with us, watch this two minute video condensing fecal sac removal by Richard's wren, a phoebe caring for a parasitic cowbird chick,* and a pileated woodpecker. Sometimes the chick actually backs up to the edge of the nest and lets fly over the side.  Occasionally the parent consumes the sac.

So why do the parents sometimes eat the fecal material?  Baby birds' guts don't start with all the bacteria necessary for complete digestion of the food.  There can be a lot of available calories in poop if you hold your nose and birds can't hold their noses but they can reduce the number of hunting trips needed for their own nutrition.  Once the bacteria in the feces build up the parents stop eating it, apparently "a matter of taste."

* The phoebe and cowbird footage is by Linda Bower, skillfully photographing poop once again.

Thursday, August 13, 2020

Odorous ants

3 mm ant on counter

Last month we started to notice a couple of these small black ants exploring our kitchen countertop in Springfield.  Out in nature at the creek we are very tolerant of even this wildlife but this was too much.  We put a few drops of Terro out where they seemed to come in through a window sill.  After a week of taking it home to feed the family, they disappeared.  We sent some photographs to James Trager who provided us an education.

"Those are "odorous house ants" - Tapinoma sessile (Remember to pronounce every vowel in Latin names. )  A very abundant, ecologically catholic (including a wide variety of things; all-embracing), and widely distributed North American "species".  A recent genetic study indicates it has in fact four different geographical-genetic populations that are likely distinct species, but so nearly identical in appearance and habits that no one has yet discerned how to separate them by eye.

They come into my house around now, too, one of the few native ants that remains abundant post invasion of my yard by the Asian pavement ant - Tetramorium tsushimae. In recent years, a colony has daily occupied my mailbox then retreated to the grass below in the evening, during the time of year when daytime air temperatures are higher than those of the soil below, and vice versa at night. " - James Trager

We too have opened the mailbox to find a huge swarm of T. sessile reading our junk mail.  Nests can contain multiple queens and thousands of workers.  For their tiny size they are very rapid, especially when disturbed.  The "odorous" title comes from a smell released from their abdominal glands which has been likened to that of rotten coconut.

 

 

T. sessile from Antwiki CC

Antwiki.org ("Every Ant Tells a Story - And Scientists Explain Their Stories Here") is always a great place to start finding information on ants.  They have a huge article on our odorous visitor.  Here is the opening chapter.

"This species is extremely adaptable, nesting in a wide range of sites and being found in numerous habitats. Nests in open soil, under stones and logs or in dead wood, under loose bark, in cavities of plants or in plant galls, under leaves and rubbish piles and even bird nests. The site of the nest is changed often. Nests are populous with size varying with age (from 2,000-10,000 workers) and contain multiple queens. Brood is found in nests from April until September. Reproductives are found in nests from May until October, flights occur in June and July. This species forages singly from trails and are active during both day and night. They tend Homoptera and feed on dead insects or the juices of decaying fruits and vegetables. It is strongly attracted to sweet substances. It is a common house-infesting ant. "  Antwiki

This just shows just how adaptable species like odorous ants, wood rats and recluse spiders can be, learning how to live on society if not in it.


Tuesday, August 11, 2020

Redbud Caterpillars

Strolling along our lane I looked up at the underside of some redbud leaves and found this colorful little caterpillar.  A quick look at INaturalist identified it as Norape ovina.   Closeup it looks warm and fuzzy but its aposematic colors warn predators and curious humans to stay away from it.  It is a member of the Megalopygidae family whose caterpillars are frequently referred to as "poisonous." To us the risk is from touching them.  Those long fuzzy hairs look soft, even inviting.  They are deceptive, covering upright poisonous setae arising from the yellow bumps. They leave a burning sensation that some liken to a yellowjacket sting.  Some people will have blistering and a long lasting rash.  Hard to believe that this will grow up to be a cute and distinctive moth, the white flannel moth.  Its host plants are redbud and hackberry trees.
 John and Jane Balaban
 
N. ovina is in the same family as the notorious saddleback caterpillar.  Its defense is more obvious with exposed hollow setae, much like tiny hypodermic needles.  At the base of each one there is a there is a poison gland.  One look at this photo by M. J. Raupp should make you go "ouch."
 
Across the drive I found some redbud leaves that were neatly folded with strands of silk.  Inside the was a black and white larva, cuddled up with little pellets of frass.  On close inspection it also had hairs, a single hair for each body segment.  A quick visit to INaturalist identified it as a redbud leaffolder, Fascista cercerisella. 
 
 
 
These caterpillars hide out all day, chewing the upper surface of the leaf which leaves it to brown out until they move to another leaf in the night.  The single tiny hairs are not the least bit threatening so its only apparent defense was hiding out.  That is until I took one home and unfolded a leaf in a plastic dish.  This is a little speed demon, capable of twitching evasive action as seen in this video.
 
Adult leaffolder - Mark Dreiling CC
The adult leaffolder moth is only a quarter of an inch long.  They have two to three generations a year and Oklahoma State's Entoweb describes possible severe damage to foliage.  I suspect this is true in an urban area where there is a single redbud tree but in the valley where I am seldom out of sight of three redbuds, I have to search hard to find any folded leaves.  Once again, this degree of damage has to do with our planting a single tree in an urban area.  Spreading out among the understory of a forest is a much better survival technique for our little racing F. cercerisella.

I kept three cats in a tupperware container, feeding them fresh leaves that they always kept folded up.  Today I was rewarded when I unfolded the leaves and found this pupa inside.  This is the second generation of three so I hope to have the moth climb out this month.


Sunday, August 9, 2020

Golden Digger Wasp

Some great videos of a great golden digger wasp by Georgia Virnig inspired this blog.  The example above was one I found in 2015 stumbling along on its last legs.   I picked it up after it died for pictures.  It is in the Sphecidae family of thread-waist wasps whose skinny waist you can see in the picture below.

We will start with her story.

"We've been fascinated watching several very industrious female great golden digger wasps excavating tunnels between some paving bricks off our porch. I witnessed one dragging a katydid into it's burrow, but of course I didn't have my phone at that moment. The diggers were very gracious in letting me video them dig though! 
There were several wasps working in this area, and I watched them for a week or so. I saw 2 working at one time on separate tunnels. Whether these two came back day after day or if there were others working is a question! There are probably 8 or so tunnel sites."

The great golden digger wasp's (GGD) formal name is Sphex ichneumoneus, named "ichneumoneus" for the Greek for tracker.  They are close kin to giant cicada killer wasp, Sphecius speciosus, and both can be well over an inch long and have threatening aposematic colors.  They are not threatening to humans although I wouldn't want to pick one up as a test.The adult wasps feed on sap fluids and nectar but are most famous for tracking down large prey to package as baby food for their larvae.  The GGD specializes on orthoptera (crickets, grasshoppers and katydids), hauling them into nesting tunnels.  Although not considered social nesters, it is common to find several in the same area, more like a popular suburb,

"This species spends about 1–2 months as an adult before dying. Females excavate long vertical main tunnels in the ground, with nest cells located in short side tunnels. Most nests have 2 or 3 cells, and a female usually digs 5 or 6 nests during her few months of summer activity. Sometimes two females will jointly provision a single nest. The young pass the winter underground in their nest burrows before emerging as adults the following year."  MDC Discover Nature

In Georgia Virnig's video here you can see the GGD females hard at work digging their nests and then covering them up.  At 0:07 you can see one move a rock that doesn't meet its standards.  At 1:38 there is a good demonstration of using its head to tamp down the rocks while vibrating which packs them tighter. psyche.entclub

 So "what good are they" we are asked as if everything should be good for humans.  Well, they have a role in nature like all of us.  They pollinate flowers, control populations of orthoptera that chew garden plants and in turn are consumed by snakes, birds and some mammals.  Like many other animals, they even have their own specialized parasites, another branch of the food web.  And they areate the soil with their tunnels.  What is not to like!
 
More detail is at  Texas A&M Beneficial Insects.

Lump in the Road

I found this two inch fungus in the middle of a steep gravel trail above the valley floor, a curious leathery lump.  It was attached to an exposed root and when I peeled it off it exposed an interesting wavy underside.  I sent it to Mark Bower who said "you have a very interesting mushroom. It is Coltricia montagnei, which is an uncommon polypore. Way to go. I’ll include it in our Bull Creek list."  

He included this link from Dianna Smith with much better photographs like the one below.  C. montagnei is a very interesting mushroom from a mycologists point of view.  Mushroom Expert Michael Kuo says "This thing is pretty amazing. It's a polypore, but it develops gills. Not only that, but the gills are concentric, rather than radiating out from the stem in lines!"

C. montagnei - Dianne Smith - Fungikingdom.net

C. montagnei  is a polypore that like most others is saprobic and is commonly found on dead or dying wood.  Its mycelia form a network of threads that gradually break down wood and return nutrients to the soil.  Without these services of fungi you can imagine the piles of dead logs that would remain present for years in a forest, preventing any new growth.

Polypores form large fruiting bodies with pores or tubes on the underside, and  frequently are on the side of trees forming a shelf, thus the common name bracket fungus.  They vary in appearance and some are quite beautiful.

Violet-Tooth Polypore, Tricaptum biforme - Mark Bower

Stopping in the woods to check out a brown lump paid off.  In the words of a well known philosopher, "Life is like a box of chocolates..................................."

Wednesday, August 5, 2020

Feeding a Brown Recluse




The current social isolation has led people to take up gardening, make home improvements, do more cooking, etc. So naturally naturalist Linda Bower tried raising brown recluse spiders (BR). I had better let Linda explain.

"I have been living with a brown recluse infestation for 21 years. My house was built in the late 1800's, a perfect home full of cracks and crevices for their sheet-type webs and infamously reclusive lifestyle. July and August are the worst. They come out of the cracks when it is hot and dry. They are in my shower, laundry basket, closets, in every corner, behind my coffee maker, and yes, my bed. I hunt them at night with a vacuum cleaner and spotlight. In all that time I had never seen them kill. I just had to film them."

Linda raised one of the recluses, feeding it sawfly larvae (see this blog) which were attacking her silky dogwood. One spider killed three sawfly late instar larvae in quick succession. One of the larvae fought back, but a few quick strikes and it was dead. The second died quickly, too, but didn't fight it. The third is in this video where the spider kept jumping back rather than hang on, watching it ooze away. Spoiler alert - could spoil your dinner. The sawfly larva is harmless so why didn't it hang on for the kill?

One possibility is that it used all its venom on the first two larvae. Another possibility from Chris Barnhart is in a paper from 2008 in the Journal of Arachnology. The author raised and fed BR with prey of different sizes, both live, freshly killed or dead prey up to a month old. The study concluded that they preferred smaller prey that was fresh but will feed as scavengers when necessary.

"Overall, recluses preferred live prey over dead, but their choice was influenced by all three variables. Recluses were more likely to scavenge when presented with large live prey paired with dead prey of equal size than when presented with small live and dead prey. Spiders that had fed recently were more likely to scavenge. Finally, recluses preferred dead prey that were freshly killed or less than 24 hours old to items dead for longer periods." The Journal of Arachnology 36:140–144, 2008
Linda kept seven recluses in an aquarium, and being Linda, she had to go on to get this video of a recluse cannibalizing and of course pooping. She also captured it in this video cleaning its chelicera with the tiny fangs at the tip. These are so small that they can't penetrate any clothing.



Recluse fang - Linda Bower

Missouri is in the highest density region for brown recluses. That and more on identification is in this previous blog and in this Wikipedia entry.

Much more details on anatomy etc. is at Bugsinthenews.

Sunday, August 2, 2020

Black Corsair


Ben Caruthers sent me this great shot of a little black corsair bug which he identified and sent in to Bugguide.  "It was walking across my patio. I don't remember seeing one in this stage before. It looks a little like a watermelon sliced in half. I think this may be an adult female."

I would agree that it is a female.  BugEric says:  "This species exhibits what is called sexual dimorphism.  Males are fully winged and are strong fliers.  Females usually lack hind wings and have the front wings reduced to mere pads, though there are exceptions.  They are nocturnal like the males."  Compare this to the top photo.
 
Ankle weights on the front two pair of legs - Ben Caruthers

He goes on to describe its distinctive "ankle weights or leg warmers" on the tibia or shins of the front two pair of legs.  Now look at the legs above.  This is a dense pad of hairs that exude a film of oil, allowing "the bug to chase prey over slick substrates, cling to struggling victims and grip a mate in the case of males."

The black corsair, Melanolestes picipes, is also called the black May beetle-eater, a name reminiscent of the "purple people eater" of musical fame.  It is a species of corsair in the Reduviidae family. More famous for the assassin bugs, most family members are ambush predators, stabbing prey and injecting digestive juices before sucking out the nutrition.  As you may have guessed, they feed on May beetles, Phyllophaga, attacking them from behind, holding on with spongy pads on the legs.

Like assassin bugs in general, you don't want to make them mad.  The males in particular are attracted to lights, probably because prey insects are also attracted there.  The corsairs can administer a painful defensive bite that you will long remember.