Brazilian White Knee Tarantula Care Guide

Acanthoscurria geniculata

The Brazilian White Knee Tarantula (Acanthoscurria geniculata) is one of the most recognizable and popular large tarantulas for sale in the United States hobby. Famous for its bold black coloration contrasted by bright white banding across the legs, this massive New World species is prized for its aggressive feeding response, hardy nature, and impressive adult size.

Native to the tropical regions of Brazil, the Brazilian White Knee is a fast-growing terrestrial tarantula that adapts well to captivity and is often recommended for keepers wanting a large, active display species. While generally manageable, this species can be defensive and possesses potent urticating hairs that should be respected.

Brazilian White Knee Tarantula Overview

Appearance & Coloration

The Brazilian White Knee is instantly recognizable due to its dramatic black-and-white patterning. Thick white bands sharply contrast against deep black legs and body, giving this species a bold, armored appearance.

Adults become extremely robust and heavy-bodied, making them one of the most visually impressive terrestrial tarantulas available.

Key features include:

• Bright white leg banding

• Velvety black body coloration

• Thick, powerful build

• Large fang size

• Dense body hair coverage

This species is often considered one of the best “display tarantulas” because of its visibility and strong feeding behavior.

Natural Habitat

Acanthoscurria geniculata originates from humid tropical regions of Brazil where it inhabits forest floors and burrow systems beneath logs, roots, and leaf litter.

The environment is typically:

• Warm year-round

• Moderately humid

• Dense with organic debris

• Rich in hiding opportunities

Unlike arboreal species, the Brazilian White Knee spends nearly all of its time on or near the ground.

Brazilian White Knee Temperament

This species is known more for feeding aggression than outright aggression toward keepers.

Typical behaviors include:

• Powerful feeding responses

• Defensive hair kicking

• Occasional threat postures

• Bulldozing enclosure decor

Many specimens become highly food-motivated and may rush movement inside the enclosure.

While some individuals remain calm, others can become defensive during maintenance.

Enclosure Setup

The Brazilian White Knee thrives in simple terrestrial enclosures with adequate floor space and moderate humidity.

Recommended Enclosure

Spiderlings

• Small deli cup or sling enclosure

• Slightly moist substrate

• Small hide

Juveniles

• 5–10 gallon enclosure

• Cork bark hide

• Water dish

Adults

• 10–15 gallon terrestrial enclosure

• Deep substrate layer

• Secure hide structure

• Good ventilation

Avoid excessive climbing height, as large terrestrial tarantulas can injure themselves from falls.

Best Substrate

This species appreciates moisture-retaining substrate that allows occasional digging.

Good substrate options include:

• Coconut fiber

• Organic topsoil

• Bioactive tropical substrate

• Reptisoil blends

Maintain:

• Slight moisture in lower substrate layers

• Dry upper surface

• Good airflow to prevent stagnant conditions

Temperature & Humidity

Ideal Conditions

• Temperature: 75–82°F

• Humidity: 65–75%

Provide:

• Overflowed water dish occasionally

• Light moisture in one enclosure corner

• Proper ventilation

The Brazilian White Knee tolerates slight humidity fluctuations well but should not be kept excessively dry long term.

Feeding Guide

The Brazilian White Knee is legendary for its feeding response.

Feeding Options

Spiderlings:

• Flightless fruit flies

• Small roaches

• Pinhead crickets

Juveniles & Adults:

• Dubia roaches

• Crickets

• Red runner roaches

• Superworms

• Hornworms occasionally

Feed:

• Spiderlings: 2–3 times weekly

• Juveniles: Every 5–7 days

• Adults: Every 7–14 days

This species typically attacks prey with extreme speed and enthusiasm.

Molting & Growth

Acanthoscurria geniculata grows quickly under proper feeding conditions.

Premolt signs include:

• Bald abdomen darkening

• Refusal to eat

• Reduced movement

• Increased hiding

Freshly molted specimens display especially vivid white coloration.

Never feed immediately after a molt. Allow:

• Spiderlings: several days

• Adults: 1–2 weeks

for the exoskeleton and fangs to harden fully.

Handling & Safety

Handling is not recommended.

Although not considered dangerously venomous, the Brazilian White Knee possesses irritating urticating hairs that can cause:

• Skin irritation

• Eye irritation

• Respiratory discomfort

Large adults also possess substantial fang size capable of painful bites.

This species is best appreciated inside the enclosure.

Is the Brazilian White Knee a Good Beginner Tarantula?

For many keepers, yes.

The Brazilian White Knee is often recommended for beginners wanting:

• A large species

• Strong feeding behavior

• Fast growth

• Bold coloration

• Visible activity

However, beginners should still understand:

• Proper humidity management

• Hair irritation risks

• Defensive feeding behavior

Compared to slower, calmer beginner species, this tarantula is more intense but still manageable for prepared keepers.

Why Keep a Brazilian White Knee Tarantula?

The Brazilian White Knee remains one of the most iconic tarantulas in the hobby because it offers:

• Massive adult size

• Incredible black-and-white coloration

• Explosive feeding responses

• Hardy captive care

• Fast growth

• Excellent display behavior

For keepers wanting a bold, active, and visually striking terrestrial tarantula, Acanthoscurria geniculata is one of the best tarantulas for sale in the hobby.