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The Big 5 are five potentially dangerous bugs.  Though we do not by any means endorse any wholesale extermination of the creatures on this list, we would caution all of our readers to treat these guys, though more are actually gals, with the utmost respect.  They will all bite and or sting, and they are all venomous.  There are no doubt deaths that can be associated with most if not all of them, though we would also add that the death to survival rate is very low.  We would now like to introduce you to The Big 5, though we expect that there will eventually be more than five creatures so tagged.

#1:  Tarantula Hawk
It’s really big, it flies, it announces itself with a buzz that sounds like a small airplane, and it advertises with aposematic coloration (orange and black), an it has a really big stinger, at least the female does.  There are not many creatures that can take on a Tarantula and win, but the Tarantula Hawk seems to have no problems perpetuating the species by feeding upon the meat of a tarantula during its formative period.

Tarantula Hawk

Update:  August 9, 2011
We just received this comment on a Tarantula Hawk Posting:
“Went back to the location where I took the Tarantula Hawk Pic hoping to see a bit more. Saw one dragging a male tarantula along and got to close. You are correct they have a very painful sting, got me on the hand twice. I dropped the camera went back to get it and got zapped again, this time on my calf. Being handicapped and unable to run, though I did a fairly good impression of all three stooges melded into one trying to make my escape, I will take appropriate measures next time I try to get that close to something and its food. I almost had to have my ring cut off my hand it swelled up so fast. The only pics taken that day were of me after a shot of benadryl, not so hilarious pics taken by my ‘firends’ while I was passed out from the benadryl and drooled on the sofa. Those stings are about on par or worse with the few scorpion stings I have had in the past. A regular wasp or bee sting pales in comparison. I am just glad that I did not have a very severe allergic reaction. So be warned do not attempt to get to close to these flying strike force wasps once they have their prey in ‘hand’.”

#2:  Bark Scorpion
Bark Scorpions in the genus
Centruroides are among the most dangerous North American Scorpions.  Here is what BugGuide has to say about the sting of several species of Bark Scorpions:  “The sting of most scorpions is not serious and usually causes only localized pain, some swelling, tenderness and some discoloration. Systemic reactions to scorpion stings are rare.
The sting of one of our scorpions, however, Centruroides sculpturatus(until recently thought to be the same as Centruroides exilicauda), the Arizona Bark Scorpion, can be fatal. Most healthy adults are not at significant risk- only children, with their smaller body size, are in danger (treatment with antivenom has pretty much put a stop to deaths where available, but bark-scorpion stings should still be taken very seriously). The site of the sting does not become discolored.  Another scorpion known to have an intense sting is Centruroides vittatus, but no deaths have been attributed to it directly.”

Bark Scorpion

#3:  Red Headed Centipede
Most of our reports of Red Headed House Centipedes,
Scolopendra heros, come from Oklahoma and Texas and they are reported to grow as large as 8 inches in length.  All Centipedes have venom, but the Tropical Centipedes in the order Scolopendromorpha are generally considered the ones with the most virulent venom.  There are several subspecies of Scolopendra heros, and there are also numerous color variations.  Not all individuals have a red head.

Red Headed Centipede

#4: Black Widow
With her glossy black body and red hourglass marking, the Black Widow Spider is an icon of warning coloration.  The venom of the Black Widow is a powerful neurotoxin, and according to Emedicine Health, it is described as:  “Local pain may be followed by localized or generalized severe muscle cramps, abdominal pain, weakness, and tremor. Large muscle groups (such as shoulder or back) are often affected, resulting in considerable pain. In severe cases, nausea, vomiting, fainting, dizziness, chest pain, and respiratory difficulties may follow.  The severity of the reaction depends on the age and physical condition of the person bitten. Children and the elderly are more seriously affected than young adults.   In some cases, abdominal pain may mimic such conditions as appendicitis or gallbladder problems. Chest pain may be mistaken for a heart attack.   Blood pressure and heart rate may be elevated. The elevation of blood pressure can lead to one of the most severe complications.   People rarely die from a black widow’s bite. Life-threatening reactions are generally seen only in small children and the elderly.”


Black Widow

#5:  Cowkiller
The Cowkiller is a female Velvet Ant, a flightless wasp that is alleged to have a sting painful enough to kill a cow.


Runner-Up:  Creechie
Unlike the Big 5, the runner-up, the Paederus Rove Beetle, does not bite or sting, but it can cause an horrific skin reaction by merely touching it.  Most of our reports of Creechie (African name) where it is also called the Acid Bug, AKA Cari-Cari in Malaysia, Potó in Brazil  and potentially Bicho de Fuego in Panama, come from tropical countries.  Though most of our reports of Paederus Rove Beetles have come from Africa, Asia and South America, we did receive a report from Arizona two years ago and one from West Virginia in 2008 in December which we imagine means Creechies can survive the cold.  Paederus Rove Beetles also sport aposematic coloration.

Creechie in Camaroon or Cari-Cari in Malaysia

 Runner-Up:  Muskmares
Walkingsticks in the genus Anisomorpha are commonly called Two Striped Walkingsticks or Muskmares. The second common name is due to the frequency that these Walkingsticks are found in the act of mating.  These Muskmares are capable of spraying a noxious substance with great accuracy over some distance, and they are good at hitting the eyes of a potential threat.  The effects wear off shortly, but will cause the eyes to water and blur as well as sting.  The latest information posted to BugGuide has the potential for harm as more serious:  “Members of this genus can deliver a chemical spray to the eyes that can cause corneal damage.” 

Mating Muskmares

Update:  August 10, 2014
Runner-Up:  Asp
A comment today has prompted us to add the Asp, or Southern Flannel Moth Caterpillar, to The Big 5 tag.  This stinging caterpillar is reported to have a very painful sting.

Asp or Southern Flannel Moth Caterpillar

Asp or Southern Flannel Moth Caterpillar


Frightened and curious
Location: Victoria, B.C.
June 23, 2011 10:56 pm
Hey this spider has been living in the corner of our crawlspace for I don’t know how long. I found tons of dead ants and flies around its nest so it had plenty to eat. Also has two egg sacs. When I initially saw it I thought it was a Black Widow, but it has no hour glass on the bottom and its reddish-brown on the top side. What is this thing? I’m scared to kill it (we are moving and i’m sure the new owners won’t want a huge spider nest in their crawlspace), maybe its a new species, idk.
Signature: Not sure what this means but sign it well!

False Widow

Dear Not sure …,
This appears to be a False Widow,
Steatoda grossa.  Though they are not considered to be dangerous, BugGuide does note:  “The bite of this spider can produce symptoms that are similar, but much less severe than those of a black widow bite. In some cases blistering may form at the site of the bite along with physical discomfort that lasts for several days.”  We have also read reports that False Widows prey upon Black Widows, so that may be added incentive to allow them to cohabitate with you.

black widow with bess beetle
Location: Garner/Raleigh NC
April 28, 2011 6:49 am
Greetings! I don’t often have anything to post, but here’s some shots I took this morning of a black widow spider that lives in a crack in the brick mortar outside the front door of where I work in Garner, NC. I noticed the web some time ago, but couldn’t tell what was in there until it came out to ’web up’ this rather large meal of what I believe to be a Bess beetle. Sure do hope it doesn’t decide to come inside!
I apologize that the one pic of the front came out so blurry, but I had to put the camera down on the ground to take it & couldn’t see the screen. I included it anyway to possibly help identify age, as I know the spots on the back mean it is younger.
Really enjoy checking out your site, and have had many chuckles over some of your replies to those ’challenged’ posters who don’t quite get the spirit of your site. Rock on!
Signature: thank God for macro lens

Black Widow Eats Bess Beetle

Dear tGfml,
We are really impressed with this incredible Food Chain documentation.  We agree that the prey is a Bess Beetle, one of the few insects that actually has family values where adults care for and feed larvae.  Both adults and larvae are capable of making sounds by stridulation and it is believe that the sounds are a form of communication.  BugGuide has a very informative page devoted to this family of interesting beetles.  When the Black Widow matures, she will lose all of her red spots and only the red hourglass marking under her abdomen will remain on her otherwise glossy black surface, making her a strikingly distinctive creature.  Black Widows are shy, hiding by day, though they can often be found in the open in their webs once darkness falls.  Though they are not aggressive spiders, readers should treat Black Widows with respect as their neurotoxic venom is quite potent.  Again, BugGuide has a marvelous information page on Widow spiders.

Black Widow eats Bess Beetle

Spider and Young
Location: Perth, Western Australia
January 22, 2011 5:09 am
I found this spider and her young in a messy web in the branches of a small gum tree in my garden. I am curious to know what type they are. Photo taken 20/01/11.
Many thanks
Signature: Tanya Bennett

Cobweb Spider

Hi Tanya,
We really love your photograph, which we believe shows a Cobweb Spider or Comb Footed Spider in the family Theridiidae
with her brood.  The family includes the notoriously venomous Red Back Spider in Australia and Black Widow in North America, but most of the members in the family are quite benign.  It appears that the Spiderlings in your photo are taking advantage of feeding off of a Fly that has become ensnared in their mother’s web.  We were unable to conclusively match your Spider to any of the Comb Footed Spiders on the Brisbane Spider website.

Hi Daniel,
Many thanks for your quick response, very interesting to find out what the spider is, she is still in her curled up leaf with her babies today.
Kind regards

Brown Widow catches a solifuge
Location: Masai Mara, Kenya
January 11, 2011 11:44 pm
Hi Daniel,
A while ago, I sent you a picture of a tiny little solifuge that we weren’t able to identify. The other day, I watched the same solifuge (or at least one of the same species) running across the floor of my tent to the corner behind my toilet. It was the wrong corner to run to, as there’s a resident Brown Widow (Latrodectus geometricus) that lives behind my toilet. This was the result. I got a few more pics, but they were all out of focus as I was to excited to hold the camera steady.
Signature: Zarek

Brown Widow eats Solifugid

Hi again Zarek,
Thank you for sending us documentation of this awesome Food Chain encounter, a Brown Widow ensnaring a Solifugid.

Weird Spider
Location: Sacramento, Ca
January 10, 2011 11:31 pm
We found this spider in a towel in our backyard and weren’t sure what it was. Can you help??
Signature: Alysha

Juvenile Western Black Widow

Dear Alysha,
This is a juvenile Western Black Widow.  This female will eventually lose the intricate markings and mature into a glossy black spider with a red hourglass marking on the underside of the abdomen.  If you flipped this juvenile over, you would see the hourglass.  You may compare your spider to this image on BugGuide.