Invertebrates

Scorpions, spiders, and the stings worth knowing.

Key

Medically serious — can need care

Venomous — bite hurts, rarely dangerous

Painful, not dangerous

Harmless

Comes indoors — shake out boots & bedding

Disease risk (not venom)

Common — you'll see these

Occasional — now and then

Seldom — keep an eye out

Elusive — you may never see one

subtitle = binomial (scientific name)

Scorpions

Arizona bark scorpion

Centruroides sculpturatus

You find it by killing the lights: a UV torch burns it electric blue-green out of the dark. The only US scorpion whose sting is a real emergency, and the one that climbs walls indoors.

Desert hairy scorpion

Hadrurus arizonensis

The biggest scorpion on the continent, and close to the mildest: its sting runs about bee-level, the heavy pincers paid for with weak venom. The small, slender bark scorpion is the serious one.

Spiders

Western black widow

Latrodectus hesperus

Real venom, small dose: her toxin floods your own nerves, but no one in the US has died of a widow bite since 1983. The bite finds a bare hand put into a dark box without looking.

Desert recluse

Loxosceles deserta

The wound gets blamed far more often than the spider gets found. A native desert recluse, and properly named: hundreds can share a house unbitten. The tell is six eyes, not the faint violin.

Desert blonde tarantula

Aphonopelma chalcodes

A big desert tarantula whose bite is no worse than a bee sting; its real defense is flicking barbed belly hairs. The ones wandering in fall are males, out to find a mate before the cold.

Stinging Insects

Tarantula hawk wasp

Pepsis spp.

The most painful sting in the desert does almost no harm. The venom is built for spiders; on a person it is a five-minute bluff. Docile otherwise, and only the females sting.

Velvet ant ("cow killer")

Dasymutilla spp.

Not an ant but a wingless female wasp, walking the open dirt unbothered. A stacked armor-and-sting defense means almost nothing eats her; "cow killer" is about pain, not danger.

Africanized honeybee

Apis mellifera scutellata (hybrid)

You can't tell it from a regular honeybee, and the venom is no stronger. The danger is arithmetic: one disturbed colony throws 100 to 1,000 stings where a European hive throws 10 to 20.

Centipedes & Others

Desert centipede

Scolopendra polymorpha

Its name means 'many forms': one species turns up tan, brick red, olive, even blue with turquoise legs. Painful, though the bullet-ant reputation belongs to its giant cousins, not this one.

Conenose (kissing) bug

Triatoma rubida

Over 40% of Tucson's kissing bugs carry the Chagas parasite, yet almost nobody here catches it: the bugs tend to leave before they defecate. The real risk is the allergic bite.