The Brazilian whiteknee tarantula (Acanthoscurria geniculata) is a species of tarantula from Brazil that is commonly kept as a pet.
The body and legs of the Brazilian whiteknee tarantula are a deep black color, though occasionally the legs may be slightly lighter in coloration. This contrasts the bright white bands on its legs, which are generally considered to be the main reason for its subjective beauty. The males are smaller and less intensely colored. This is a larger species of tarantula than the norm, with the length of the body reaching up to 9 centimetres (3.5 in). These tarantulas are fast growing, usually taking around 3–4 years to reach a mature leg-span of 8.5 inches for females.