Phidippus johnsoni 'Red-backed Jumper'
A striking, hardy species with a vivid red abdomen — one of the easiest jumping spiders to keep.
About Phidippus johnsoni
Phidippus johnsoni is one of the most recognisable jumping spiders in North America. Found across western North America from British Columbia to Mexico, it inhabits a wide range of environments — grasslands, scrub, forests, and suburban gardens. Adults are 8–14 mm in body length, with males displaying a uniformly bright red abdomen. Males have black faces and iridescent green chelicerae; females are slightly larger and more variable in colour, often with a red abdomen bearing a prominent black dorsal stripe, or predominantly dark.
P. johnsoni is exceptionally hardy, tolerating a broader temperature and humidity range than most commonly kept jumping spiders. This resilience, combined with their bold temperament and manageable size, makes them an excellent beginner species. Females live 1–2 years; males typically 6–10 months.
Enclosure
P. johnsoni must be housed alone. They are solitary arachnids and will kill cage-mates. Only introduce individuals for brief, supervised mating attempts.
A standard arboreal jumping spider enclosure of at least 15×15×20 cm suits adults well. They are less strongly arboreal than some Phidippus species but still need vertical space and elevated anchor points for their silk retreat. Cork bark, twigs, and small plants provide good structure. Cross-ventilation is important — mesh on two opposite sides is ideal.
Temperature & humidity
P. johnsoni comes from varied climates across western North America and tolerates a wide temperature range. Aim for 20–26°C. They handle cooler conditions better than tropical species, but avoid prolonged exposure below 18°C.
This species prefers drier conditions than most jumping spiders in the hobby. Maintain 40–60% humidity — mist one side of the enclosure lightly every 3–4 days. Over-misting is a greater risk than under-misting with this species. Never spray the spider directly.
Feeding
P. johnsoni is a confident, active hunter. Feed appropriately sized live prey every 2–3 days:
- Spiderlings: melanogaster fruit flies
- Juveniles: hydei fruit flies, small crickets
- Adults: crickets, bottle flies, mealworms, waxworms
Prey should be no larger than the spider's abdomen. Remove uneaten prey within 24 hours. Pre-moult fasting is normal — they may refuse food for days or weeks before a moult. Do not force-feed.
Handling
P. johnsoni is bold and generally tolerant of handling once settled. Let them walk onto your hand voluntarily — most will explore willingly. Handle indoors over a soft surface and keep sessions brief.
Like all jumping spiders, they have exceptional vision through their large anterior median eyes and will watch and react to your movements. Move slowly and avoid sudden gestures. Never handle during or shortly after a moult.