Acanthoscurria geniculata Care Sheet
Welcome to the world of Eight Legged Beauties, where we turn fuzzy fear into fascination!
Today we’re celebrating a bold, striking ground‑dweller — Acanthoscurria geniculata, better known as the Brazilian White‑Knee Tarantula. With its dramatic leg banding, fast growth, and powerful presence, this species is a favorite for keepers looking for a big, active, and visually stunning New World tarantula.
Meet the Species
Scientific name: Acanthoscurria geniculata
Common name: Brazilian White‑Knee, Giant White Knee, White‑banded Tarantula
Type: Terrestrial / New World
Native to: Northern Brazil rainforest region
Adult size: Up to ~8″+ (diagonal leg span) according to some care sources
Temperament: Confident / bold, defensive at times, uses urticating hairs (Types I & III) when disturbed
Lifespan: Females up to ~20 years; males much shorter
Experience level: Beginner → Intermediate — hardy and well‑documented.
Fun Fact:
Despite its size, A. geniculata grows quickly, making it one of the more dynamic & visually rewarding species for hobbyists — especially when you catch that full feeding response.
Setting Up Their Home
In the wild, A. geniculata inhabits tropical rainforest ground‑cover, digging shallow burrows under roots, logs, and leaf litter.
Enclosure Tips
• For spiderlings: Use a small acrylic box, ~3× leg span wide.
• For juveniles: Medium terrestrial enclosure, width ~3–4× leg span.
• For adults: Larger terrestrial setup, width ~3–4× (or more) leg span; height kept modest to avoid fall risk.
• Orientation: Wider than tall — emphasizes horizontal space over height.
• Security: Ensure a tight-fitting lid, well-drilled ventilation holes; these spiders can be escape artists.
Substrate
Use about ½ to ¾ of the enclosure depth of:
Organic topsoil / Terra Aranea (or similar mix)
Keep it firm but diggable
For slings: maintain one slightly damp corner; for adults: mostly dry with a moist retreat zone
Add a hide like cork bark, a fake plant, or half a flowerpot. A shallow water dish is essential, even if rarely used.
Temperature & Humidity
Setting Ideal Range Tips
Temperature 75-85°F Room temp is usually fine. Avoid heat lamps or direct sunlight.
Humidity 60-70% Keep mainly dry substrate; lightly mist or overflow water dish occasionally.
Ventilation High Proper airflow prevents mold.
Pro Tip:
Mist carefully or refresh the water dish instead of soaking the whole substrate — helps maintain humidity without drowning the enclosure.
Feeding Time
Spiderlings
Feed 2× per week
Pinhead crickets, fruit flies, or tiny roaches
Remove uneaten prey after 24 hours
Juveniles
Feed every 7–10 days
2–3 small crickets or one medium roach
Adults
Feed every 2–3 weeks
4–5 large crickets or one adult Dubia roach
Tip:
A healthy tarantula’s abdomen should be roughly the same width as its carapace.
Too plump = overfed. Too thin = time for a snack.
After a molt, always wait until the fangs are black again before offering food.
(Usually 24–48 hrs for slings, up to a week or more for adults.)
Behavior & Temperament
• Spiderlings: Can be curious but will retreat quickly when disturbed.
• Adults: Bold, fast, and confident—known for a dramatic feeding response.
• Handling: Not recommended for frequent handling — better enjoyed as a display species.
Observation tip:
Look for burrowing activity, substrate displacement, or settled behavior in hides — these often signal that the spider is comfortable.
Common Challenges
Managing high humidity without over-saturating the substrate
Providing deep substrate for burrowing while keeping lid secure
Preventing overfeeding — this species has a strong appetite
Containing its defensive hair-kicking behavior — design for minimal disturbance
Final Thoughts
Acanthoscurria geniculata (Brazilian White‑Knee) is a show-stopping and robust species — powerful, fast-growing, and visually striking. For keepers who want a big, active tarantula that’s still reasonably forgiving, this species is a dream. With the right setup — a spacious terrestrial tank, deep substrate, and balanced humidity — this white‑kneed giant can thrive and give you years of fascinating behavior and growth.