Aphonopelma johnnycashi

Physical description and identification

Aphonopelma johnnycashi has the build shared by all North American Aphonopelma tarantulas: a low, broad carapace, thick legs, a plump abdomen and a dense coat of setae that gives the whole animal a velvety look. What sets it apart in the field is less the shape than the colour of the mature males, and above all the place it is found.

Adults

• Size: a large female can reach a leg span of about 150 mm (roughly 6 inches), although many adults are smaller. Body length is far less impressive than the span suggests — most of the apparent size is leg. Females are heavier and shorter-legged; mature males are slender with long, spidery legs.
• Colour: this is the species' signature. Mature males are uniformly black, with a slight sheen on the freshly moulted carapace — the feature that earned the tarantula its name. Females and immatures are dark brown to medium brown, sometimes with a slightly paler carapace, and are far less eye-catching.
• Eyes: eight small eyes clustered on a single raised tubercle at the front of the carapace, typical of mygalomorphs. The spider relies on vibration rather than sight, which is why a tarantula will often ignore a hand until it touches a leg.
• Distinctive features: like other New World theraphosids, both sexes carry barbed urticating hairs on the upper abdomen and kick them off with the hind legs when harassed. Mature males have tibial hooks on the front legs and enlarged pedipalp tips. Because several Californian Aphonopelma look broadly alike, reliable identification usually depends on the shape of the mature male's palpal bulb together with the locality of the record.

Eggs and egg sac

The female mates in her burrow and later spins a silk sac around the clutch, holding it deep in the tunnel. Theraphosid egg sacs of this size normally contain a few hundred eggs. The female guards and periodically turns the sac, and may carry it toward the entrance to warm it, abandoning it only once the spiderlings emerge.

Spiderlings

The young stay in the burrow through their first moult, then scatter to dig their own small tunnels. Growth is slow and measured in years rather than months, with each increase in size requiring a full moult. Our guide to the spider life cycle explains the process, which in tarantulas is repeated for decades in females.

The web and hunting

This is not a web-building spider. A. johnnycashi is an ambush predator that digs a burrow under a rock, a log or a bank of soil, lines the walls with silk and waits at the entrance after dark. Silk laid around the mouth of the burrow carries vibration and tells the spider when a beetle or cricket is within reach. Prey is grabbed, bitten and dragged below; the tarantula does not chase anything far.

Where Aphonopelma johnnycashi lives

The species is endemic to California and, as far as current records show, confined to the western foothills of the Sierra Nevada. The type specimens come from the country around Folsom in the American River drainage — hence the name — and the known range runs along the foothill belt from there to the south, from low elevations up into the hills.

Calling this habitat desert, as some accounts do, is misleading. The Sierra foothills have a Mediterranean climate: hot, dry summers and cool, wet winters. The tarantula lives in blue oak woodland, chaparral, grassland and the broken granite slopes between them, digging into banks, road cuts and the soil beneath rock slabs. Those burrows are the key to surviving the dry season, holding humidity through months when the surface soil bakes. Like other members of the genus it is strictly terrestrial and nocturnal, and it does not live in houses.

Is Aphonopelma johnnycashi venomous?

Yes, in the same sense every tarantula is venomous: it has venom glands and uses them on insects. The venom of North American tarantulas is weak in human terms and no bite from the genus has been shown to cause serious systemic illness. There is no antivenom because none is needed.

The defence that actually matters to a person or a dog is the patch of urticating hairs on the abdomen. Kicked into the air, these barbed bristles cause itching, redness and small welts on skin, sneezing if inhaled, and genuine, sometimes lasting inflammation if they reach the eye.

Can Aphonopelma johnnycashi bite?

It can, but a bite is a last resort. A cornered tarantula will first try to retreat, then rear up with the front legs raised and fangs exposed, then flick hairs. Bites occur mainly when the animal is picked up, trapped in clothing or pressed against skin. The usual result is local pain from fangs that are several millimetres long, some bleeding, and redness and swelling that fade within a day or two — the pain is often compared to a bee sting.

Wash the puncture with soap and water, use a cold pack for the swelling, and keep the area clean while it heals. See a doctor if swelling spreads well beyond the bite, if you feel faint or short of breath or develop hives (that is an allergic reaction, not venom toxicity), or if the wound looks infected later. If urticating hairs are involved, lift them off the skin with adhesive tape rather than scratching, and never rub your eyes — ocular exposure needs an ophthalmologist.

Ecological importance and behavior of Aphonopelma johnnycashi

In the foothill ecosystems it occupies, this tarantula is one of the larger invertebrate predators at ground level. It hunts at night from the mouth of its burrow, taking crickets, cockroaches, beetles, grasshoppers, other spiders and occasionally small vertebrates such as lizards. Because it can survive long fasts and retreats underground in bad conditions, a population persists through droughts that flatten shorter-lived insect predators.

Natural predators: coyotes, foxes, skunks, raccoons, owls, hawks, snakes and lizards all take tarantulas, and spider wasps of the tarantula hawk group are specialist enemies — the wasp paralyses the spider, buries it and lays an egg on it so the larva feeds on living tissue.

Prey-predator dynamics: steadily removing insects while feeding vertebrate predators puts the species in the middle of the foothill food web rather than at the top of it.

Seasonal behavior: females are sedentary and may hold the same burrow for many years. Mature males do the opposite — after a final moult they leave for good and walk in search of females during the warm months, which is when most sightings and most road casualties happen. A male drums at a female's burrow entrance, mates if accepted, and survives only months afterward, while females can live for decades.

Relationship with humans: encounters are harmless and the spider is not aggressive. Its slow life history is its weak point: a female that takes close to a decade to mature cannot be replaced quickly, so collecting adults from the wild and habitat loss in the rapidly developing foothills matter far more to the species than any risk it poses. In the pet-keeping hobby, animals of this kind are kept in a deep, dry substrate that lets them burrow, and responsible keepers work only from captive-bred stock.

Similar spiders and how to tell them apart

Quick facts

Did you know?

• The name is a double reference: the type locality lies near Folsom, the prison of Folsom Prison Blues, and the mature males are black, like the singer's stage wardrobe.
• The species was one of fourteen new tarantulas described in a single 2016 paper that reviewed every Aphonopelma in the United States and reduced a chaotic list of names to 29 recognised species.
• Black males are not a separate kind of tarantula: the colour appears at the final moult, so a brown juvenile male becomes a black adult overnight.
• Tarantula species in this genus are often separated less by colour than by where they live and by the fine structure of the male palp, which is why locality data matter so much to arachnologists.
• Not every tarantula has urticating hairs. Old World species, including the African baboon spiders, rely on speed and a far more painful bite instead.

In summary, Aphonopelma johnnycashi is a slow, retiring, harmless burrower with an unforgettable name — a reminder that new large animals are still being described in well-studied places like California.