Schmidt sting pain index
Pain scale for insect stings
From Wikipedia, the free encyclopedia
The Schmidt sting pain index is a pain scale rating the relative pain caused by different hymenopteran stings. It is mainly the work of Justin O. Schmidt, who was an entomologist at the Carl Hayden Bee Research Center in Arizona.
| Schmidt sting pain index | |
|---|---|
Some species representing the Schmidt sting pain index: Synoeca surinama, Paraponera clavata, Pepsis sp., Hemipepsis sp., and Vespa mandarinia | |
| Purpose | Rates the pain of different stings |
Schmidt's original 1983 paper was a way to systematize and compare the hemolytic properties of insect venoms.[1] A table in the paper included a column that rated sting pain, starting from 0 for stings that are completely ineffective against humans, progressing through 2 for familiar pains such as those caused by common bee or wasp stings, and finishing at 4 for the most painful stings. Only the bullet ant, Paraponera clavata, was given a rating of 4, although later versions of the index added two more species.
Schmidt repeatedly refined his scale, including a paper published in 1990, which classifies the stings of 78 species and 41 genera of Hymenoptera,[2] and culminating in a book published in 2016.[3]
Motivation
The Schmidt sting pain index arose from the pursuit of a larger hypothesis: that the evolution of sociality in Hymenoptera was dependent on the evolution of venom that was both painful and toxic.[4] Pain is a signal of damage in the body, but molecules that produce pain are not the same as toxic molecules, which actually cause damage. Although the painful signal acts as a deterrent, intelligent predators learn the dishonesty of this signal with repeated exposure.[3] For the early Hymenoptera that were primarily solitary, the pain alone would allow them the chance to escape. Moreover, solitary insects do not provide a high energy reward for predators, and therefore predators do not expend significant effort to hunt them.[citation needed]
However, colonies of Hymenoptera are a nutritionally rich target.[5] If there were no defenses, predators would devour the defenseless society, leaving few surviving individuals.[3] Therefore it was theorized that the development of toxicity in Hymenoptera facilitated the development of sociality, which brings various benefits, including the shared raising of young, individual task specialization, inter-colony communication, and food storage.[5] Assays for toxicity were already well characterized, so the evolutionary connection between toxicity and sociality could be studied. Schmidt developed his pain index to relate the amount of sociality to the level of pain.[6]
Development
Scale summary
Schmidt's pain scale of Hymenopteran stings is organized into levels, ranging between 1 and 4, with 4 being the most painful. However, insect stings that feel very different can be put into the same level. Thus, later versions of the scale always include a brief description of his experience being stung by each type of insect.[4]
| Level 1 | Some of the insect stings Schmidt considered to be at a pain level of 1 include the Southern fire ant, the graceful twig ant, the Western paper wasp, the urban digger bee, and most small bees. The duration of the pain of insect stings categorized into Pain Level 1 generally is five minutes or less.[2]
Many small bees are categorized into a pain level of 1, with their venom containing polypeptides such as melittin, apamin, and MCD peptide. Melittin is the main toxin of bee venom, and it damages red blood cells and white blood cells. Apamin is a neurotoxin that augments polysynaptic reflexes. MCD peptide destroys mast cells.[7] Feeling only slight pain, Schmidt described the sting of an urban digger bee, categorized into pain level 1, as "almost pleasant, a lover just bit your earlobe a little too hard."[3] Also rated into pain level 1, Schmidt has described the sting of a sweat bee as "light, ephemeral, almost fruity. A tiny spark has singed a single hair on your arm."[3] |
|---|---|
| Level 2 | Schmidt set the sting of the Western honey bee at a pain level of 2 to be the anchoring value, basing his categorization of all other stings on it.[4] He has categorized a variety of wasps, bees, and ants into pain level 2, including yellowjackets, the Asiatic honey bee, the trap-jaw ant, and the bald-faced hornet. The duration of the pain of the stings in this level is generally between five and ten minutes long. Schmidt categorized the majority of Hymenopteran stings as having a pain level of 2.[2]
The sting of a termite-raiding ant, categorized as a pain level of 2, has a similar feeling as "the debilitating pain of a migraine contained in the tip of your finger," according to Schmidt.[3] A yellowjacket's sting was described as being "hot and smoky, almost irreverent. Imagine W. C. Fields extinguishing a cigar on your tongue."[3] He also described the sting of the honeybee as a similar feeling to "The oven mitt had a hole in it when you pulled the cookies out of the oven."[3] |
| Level 3 | Most insects that are characterized as having a pain level of 3 are wasps, including the neotropical red paper wasp, the red-headed paper wasp, and Klug's velvet ant (a wingless wasp and not a true ant). The duration of the sting pain can range anywhere from one minute (such as the sting of the red paper wasp) to half an hour (such as the sting of the velvet ant).[2][3] Wasp venom uniquely contains kinin. One of the kinins found in wasp venom, "polistes kinin 3", is found to lead to similar effects on smooth musculature and circulation as bradykinin.[7]
Some ants are also rated at a pain level 3, including the giant bull ant and the Maricopa harvester ant. Schmidt considered the sting of the Maricopa harvester ant to have a pain level of 3, describing it as such: "After eight unrelenting hours of drilling into that ingrown toenail, you find the drill wedged into the toe."[3] |
| Level 4 | The highest level in the Schmidt sting pain index. Schmidt's original index rated only one such example, the sting of the bullet ant Paraponera clavata, as a 4.[1] He wrote, "Paraponera clavata stings induced immediate, excruciating pain and numbness to pencil-point pressure, as well as trembling in the form of a totally uncontrollable urge to shake the affected part."[1] In a later work, he described the sting as "pure, intense, brilliant pain...like walking over flaming charcoal with a three-inch nail embedded in your heel."[3] The bullet ant's venom primarily contains poneratoxin, a paralyzing neurotoxic peptide.[8]
He later gave the sting of a tarantula hawk species, Pepsis grossa,[a] a rating of a 4,[2] which he described as "blinding, fierce [and] shockingly electric",[3] though the duration of pain from the sting is short-lived, lasting only approximately five minutes.[2] The composition of tarantula hawk venom is unknown.[9] He also later rated the sting of Synoeca septentrionalis as a 4, describing it as "Torture. You are chained in the flow of an active volcano. Why did I start this list?",[3] saying the pain lasts up to two hours.[3] |
Entire scale
Schmidt's entire list of ratings and descriptions[3]:
| Category | Name | Latin name | Range | Description | Pain Level |
|---|---|---|---|---|---|
| ant | Indian jumping ant | Harpegnathos saltator | Asia | Ah, that wonderful wakeup feeling, like coffee but oh so bitter. | 1 |
| ant | Delicate trap-jaw ant | Anochetus inermis | South America | A tiny spark, just enough to rouse you from a dreamy stroll in the woods. A slight jolt as you return to reality. | 1 |
| ant | n/a | Bothroponera striglosa (A type of African black ant) | Africa | Timid but not painless. A pebble kicked up by a passing car ricochets off your ankle. | 1 |
| ant | Asian needle ant | Brachyponera chinensis | Native to Asia | Nightfall following a day at the beach. You forgot the sunscreen. Your burned nose lets you know. | 1 |
| ant | Big-eyed ant | Opthalmopone berthoudi | Africa | A sharp interruption as you absorb the beauty of Africa. An acacia spine just poked through your sandal. | 1 |
| ant | n/a | Ectatomma ruidum (A type of black ant) | Central America & South America | A brief searing, like tuna on a grill. The bottom of your foot is blanched but not cooked through. | 1 |
| ant | n/a | Leptogenes kitteli (A type of Asian army ant) | Asia | Simple and plain. A loose carpet tack pierces the ball of your wool-socked foot. | 1 |
| ant | Elongate twig ant | Pseudomyrmex gracilis | North America, Central America & South America | Reminiscent of a childhood bully. Intimidating, but his punch only glanced your chin, and you live for another day. | 1 |
| ant | Slender twig ant | Tetraponera sp. | Asia | A skinny bully's punch. It's too weak to hurt but you suspect a cheap trick might be coming. | 1 |
| ant | Red fire ant | Solenopsis invicta | Native to South America | Sharp, sudden, mildly alarming. Like walking across a shag carpet and reaching for the light switch. | 1 |
| ant | Tropical fire ant | Solenopsis geminata | Native to Central America & South America | You should have learned, but the carpet is the same, and when you again reach for the light switch, the shock mocks you. | 1 |
| ant | Southern fire ant | Solenopsis xyloni | North America | It happens on the third day, as you reach for the light switch, and you're wondering when you will ever learn. | 1 |
| ant | European fire ant | Myrmica rubra | Native to Europe | The prickle of stinging nettles against your skin on a hot, humid day. | 1 |
| ant | Samsum ant | Euponera sennaarensis | Africa | Pure, sharp, piercing pain. You pressed your thumb on a tack. | 1.5 |
| ant | Suturing army ant | Eciton burchellii | Central America & South America | A cut on your elbow, stitched with a rusty needle. | 1.5 |
| ant | n/a | Ectatomma tuberculatum (A large golden ant) | Central America & South America | A slow stream of hot wax poured over your wrist. You want to twist away but can't. | 1.5 |
| ant | Giant ant | Dinoponera gigantea | South America | A pulsing sting with some flavor. You stepped into a salt bath with an open wound. | 1.5 |
| ant | Giant stink ant | Paltothyreus tarsatus | Africa | You must have upset the nurses. They stuck you with a big needle and then dribbled in garlic oil. | 1.5 |
| ant | Bulldog ant #1 | Myrmecia simillima | Australia | Intense, ripping, and sharp. The dog's tooth found its mark. | 1.5 |
| ant | Red bull ant | Myrmecia gulosa | Australia | A sneaky, unassuming ache. Like a brightly colored LEGO, charming till it's lodged in the arch of your foot in the dark. | 1.5 |
| ant | Bulldog ant #2 | Myrmecia rufinodis | Australia | Shockingly sharp. A scalpel just lanced your palm. | 1.5 |
| ant | Metabele ant | Megaponera analis | Africa | A child's arrow misses its target and finds its home in your calf. | 1.5 |
| ant | n/a | Ectatomma quadridens (A type of big black ant) | South America | A burning itch to catch your attention, followed by regret, like ordering spicy chicken wings when you have a mouth sore. | 1.5 |
| ant | Bullhorn acacia ant | Pseudomyrmex nigrocinctus | Central America | A rare, piercing, elevated sort of pain. Someone has fired a staple into your cheek. | 1.5 |
| ant | Jack jumper ant | Myrmecia pilosula | Australia | The oven mitt had a hole in it when you pulled the cookies out of the oven. | 2 |
| ant | Metallic green ant | Rhytidoponera metallica | Australia | Deceptively painful. Like biting into a green bell pepper to find it is a habanero chili. | 2 |
| ant | n/a | Diacamma sp. (A type of black ant) | Asia | Nothing subtle about this one. Sudden and striking, a shard of glass on a tropical beach pulls you out of the moment as it finds a nerve in your bare foot. | 2 |
| ant | Large tropical black ant | Neoponera villosa | North America, Central America & South America | Exquisitely sharp and expertly clean. Broadway's favorite barber selects his next victim. | 2 |
| ant | n/a | Neoponera crassinoda (A type of big black ant) | South America | This one packs a punch. The dentist should have given that novocaine more time to take effect. | 2 |
| ant | Termite-raiding ant | Neoponera commutate | South America | The debilitating pain of a migraine contained in the tip of your finger. And their queen can sting like her sisters! | 2 |
| ant | African giant ant | Streblognathus aethiopicus | Africa | The white hot burn of a barbecue fork impaling your hand, paired with the grizzle of a serrated knife. | 2 |
| ant | n/a | Platythyrea lamellose (A purplish ant) | Africa | Relentless prickling throughout your body. Like wearing a wool jumpsuit laced with pine needles and poison ivy. | 2 |
| ant | n/a | Platythyrea pilosula (A sleek ant) | Africa | A torturous itch and rash with serious lasting power. Should have spent the extra money and paid for a licensed tattoo artist. | 2.5 |
| ant | Trap-jaw ant | Odontomachus spp. | Tropics worldwide | Instantaneous and excruciating. A rat trap snaps your index fingernail. | 2.5 |
| ant | Florida harvester ant | Pogonomyrmex badius | North America | Bold and unrelenting. Somebody is using a power drill to excavate your ingrown toenail. | 3 |
| ant | Maricopa harvester ant | Pogonomyrmex maricopa | North America | After eight unrelenting hours of drilling into that ingrown toenail, you find the drill is wedged in the toe. | 3 |
| ant | Argentine harvester ant | Ephebomyrmex cunicularis | South America | A ferocious pang lasting 12 hours or more. Flesheating bacteria dissolve your muscles, one by precious one. | 3 |
| ant | Bullet ant | Paraponera clavata | Central America & South America | Pure, intense, brilliant pain. Like walking over flaming charcoal with a 3-inch nail embedded in your heel. | 4 |
| bee | n/a | Triepeolus sp. (A type of parasitic bee) | North America | Did I just imagine that? A little scratch that dances with a tickle. | 0.5 |
| bee | Anthophorid bee | Emphoropsis pallida | North America | Almost pleasant, a lover just bit your earlobe a little too hard. | 1 |
| bee | Sweat bees | Lasioglossum spp. | North America | Light and ephemeral, almost fruity. A tiny spark has singed a single hair on your arm. | 1 |
| bee | Cactus bee | Diadasia rinconis | North America | A skewering message: get lost. Surprising, because you did not touch a cactus spine, until you realize it's from a bee. | 1 |
| bee | Cuckoo bee | Ericrocis lata | North America | Touch of fear unrealized. Oh, and I wanted to show how brave I was! | 1 |
| bee | Giant sweat bee | Dieunomia heteropoda | North America | Size matters but isn't everything. A silver tablespoon drops squarely onto your big toenail, sending you hopping. | 1.5 |
| bee | Western honey bee | Apis mellifera | Native to Africa and Europe | Burning, corrosive, but you can handle it. A flaming match head lands on your arm and is quenched first with lye and then sulfuric acid. | 2 |
| bee | Western honey bee | Apis mellifera (A special case, tongue) | Native to Africa and Europe | It's crawled into your soda can and stings you on the tongue. It's immediate, noisome, visceral, debilitating. For 10 minutes life is not worth living. | 3 |
| bee | Bumble bees | Bombus spp. | North America | Colorful flames. Fireworks land on your arm. | 2 |
| bee | California carpenter bee | Xylocopa californica | North America | Swift, sharp, and decisive. Your fingertip has been slammed by a car door. | 2 |
| bee | Giant Bornean carpenter bee | Xylocopa sp. | Asia | Electrifying, sharp, and piercing. Next time hire an electrician. | 2.5 |
| wasp | Club-horned wasp | Sapyga pumila | North America | Disappointing. A paperclip falls on your bare foot. | 0.5 |
| wasp | Potter wasp | Eumeninae sp. | North America | Looks deceive. Rich and full-bodied in appearance but flavorless. | 0.5 |
| wasp | Little wasp | Polybia occidentalis | Central America & South America | Sharp meets spice. A slender cactus spine brushed a Buffalo wing before it poked your arm. | 1 |
| wasp | Great black wasp | Sphex pensylvanicus | North America | Simple and presumptuous. Your younger sibling just nipped at your pinkie finger. | 1 |
| wasp | Iridescent cockroach hunter | Chlorion cyaneum | North America | Itchy with a hint of sharpness. A single stinging nettle pricked your hand. | 1 |
| wasp | Scarab hunter wasp | Triscolia ardens | North America | Like a sip of tannin, bitterness lingers. | 1 |
| wasp | Water-walking wasp | Euodynerus crypticus | North America | Clever, but trivial? A little like magic in that you cannot quite figure out the difference between pain and illusion. | 1 |
| wasp | Mud dauber | Sceliphron caementarium | Native to North America | Sharp with a flare of heat. Jalapeño cheese when you were expecting Havarti. | 1 |
| wasp | Little white velvet ant | Dasymutilla thetis | North America | Deceptive, like the name. Immediate, rashy, you want to scratch away the kiss of itch. A sand crab pinched your toe while you tanned. | 1 |
| wasp | Pacific cicada killer | Sphecius convallis | North America | Clean. Concentrated dish detergent seeps into a freshly cut finger. | 1 |
| wasp | Western cicada killer | Sphecius grandis | North America | Pain at first sight. Like poison oak, the more you rub, the worse it gets. | 1.5 |
| wasp | n/a | Eumeninae sp. (A yellow potter wasp) | North America | A surprising touch of nasty. Like a thorn hidden on the back of a rose stem as you clutch the bouquet. | 1.5 |
| wasp | n/a | Mutillidae sp. (A nocturnal velvet ant) | North America | Itch, burn, and more itch. A toothpick dipped in both itch powder and hot sauce is stuck in your thigh. | 1.5 |
| wasp | Paper wasp | Polistes versicolor | Central America & South America | Burning, throbbing, and lonely. A single drop of superheated frying oil landed on your arm. | 1.5 |
| wasp | Thread- waisted paper wasp | Belonogaster sp. | Africa | Attention getting. Like the time your classmate stabbed you with a pencil point. | 1.5 |
| wasp | Ferocious polybia wasp | Polybia rejecta | Central America & South America | Like a trick gone wrong. Your posterior is a target for a BB gun. Bull's-eye, over and over. | 1.5 |
| wasp | Baldfaced hornet | Dolichovespula maculata | North America | Rich, hearty, slightly crunchy. Similar to getting your hand mashed in a revolving door. | 2 |
| wasp | n/a | Mischocyttarus sp. (A type of paper wasp) | North America, Central America & South America | Robust, a full-bodied wake-up call. Imagine a pair of pliers latched onto your upper lip. | 2 |
| wasp | Colonial thread-waisted | Belonogaster juncea colonialis | Africa | Tenacious in a stringy way. Tangy. You can't extract yourself from the man-o-war's tentacles. | 2 |
| wasp | Unstable paper wasp | Polistes instabilis | Central America | Like a dinner guest who stays much too long, the pain drones on. A hot Dutch oven lands on your hand and you can't get it off. | 2 |
| wasp | Honey wasp | Brachygastra mellifica | North America & Central America | Spicy, blistering. A cotton swab dipped in habanero sauce has been pushed up your nose. | 2 |
| wasp | Artistic wasp | Parachartergus fraternus | Central America & South America | Pure, then messy, then corrosive. Love and marriage followed by divorce. | 2 |
| wasp | Western yellowjacket | Vespula pensylvanica | North America | Hot and smoky, almost irreverent. Imagine W. C. Fields extinguishing a cigar on your tongue. | 2 |
| wasp | Glorious velvet ant | Dasymutilla gloriosa | North America | Instantaneous, like the surprise of being stabbed. Is this what shrapnel feels like? | 2 |
| wasp | Nocturnal hornet | Provespa sp. | Asia | Rude, insulting. An ember from your campfire is glued to your forearm. | 2.5 |
| wasp | Golden paper wasp | Polistes aurifer | North America & Central America | Sharp, piercing, and immediate. You know what cattle feel when they are branded. | 2.5 |
| wasp | Yellow fire wasp | Agelaia myrmecophila | Central America & South America | An odd, distressing pain. Tiny blowtorches kiss your arms and legs. | 2.5 |
| wasp | Fierce black polybia wasp | Polybia simillima | Central America | A ritual gone wrong, satanic. The gas lamp in the old church explodes in your face when you light it. | 2.5 |
| wasp | Giant paper wasp | Megapolistes sp. | New Guinea | There are gods, and they do throw thunderbolts. Poseidon just rammed his trident into your breast. | 3 |
| wasp | Red paper wasp | Polistes canadensis | Central America | Caustic and burning, with a distinctly bitter aftertaste. Like spilling a beaker of hydrochloric acid on a paper cut. | 3 |
| wasp | Red-headed paper wasp | Polistes erythrocephalis | Central America & South America | Immediate, irrationally intense, and unrelenting. This is the closest you will come to seeing the blue of a flame from within the fire. | 3 |
| wasp | n/a | Dasymutilla klugii (A huge velvet ant) | North America | Explosive and long lasting, you sound insane as you scream. Hot oil from the deep fryer spilling over your entire hand. | 3 |
| wasp | Tarantula hawk | Pepsis spp. | North America, Central America & South America | Blinding, fierce, shockingly electric. A running hair dryer has just been dropped into your bubble bath. | 4 |
| wasp | Warrior (or armadillo) wasp | Synoeca septentrionalis | Central America & South America | Torture. You are chained in the flow of an active volcano. Why did I start this list? | 4 |
Legacy
While Schmidt's published scientific papers use a 1 through 4 number scale, an entry in The Straight Dope reported that "implausibly exact numbers" such as "bullhorn acacia ant at 1.8" were "wheedled out of him" by Outside magazine for an article it published in 1996.[10]
In September 2015, Schmidt and Michael L. Smith were co-awarded the Ig Nobel Physiology and Entomology prize for their Hymenoptera research.[11]
The Starr sting pain scale is based on the Schmidt index.[12]
See also
- Dol scale to measure pain
- Kings of Pain, a TV series with another pain index
Notes
- Reported under its synonym, P. formosa