Brazilian whiteknee tarantula (Acanthoscurria geniculata).

This spider from the suborder Mygalomorphae (with straight chelicerae) is endemic to the rainforests of northern Brazil, especially in Pará. It lives under decaying logs, rocks, or in caves. The white-kneed tarantula owes its common name to its characteristic coloration.

In adulthood, females reach between 18-22 cm in legspan length (distance between opposite legs), while males can measure up to 15 cm. Their coloring contrasts markedly: the body and legs are black, with light stripes on the joints, while long reddish and whitish bristles cover their back, including stinging bristles on the abdomen.

These non-aggressive spiders shoot urticating bristles from their hind legs when they feel threatened. These are effective against mammals, as they can irritate mucous membranes, and cause inflammation and mild skin discomfort. If this fails, they can bite with their fangs, inoculating or not venom, which is painful but not dangerous for humans.

Their diet includes small animals such as insects, frogs, birds and mice, depending on their size. When they capture the prey, the venom paralyzes and the digestive enzymes break it down, allowing the nutrients to be sucked out.

This species is popular as a pet for its size, color, and ease of care. It grows quickly and is kept in temperature-controlled terrariums, feeding on insects and small rodents.

The illustrations of this tarantula were part of the final project of the course “Ilustrando la Ciencia 5” of Illustraciencia. The project included the collection of information and sketches based on a species from the CosmoCaixa museum's cloud forest exhibit, culminating in its inclusion in a course portfolio. A video was also recorded for the course presentation and promotion on line.

Year: 2018
Technique: Pointillism, scratchboard and watercolor.
Illustration type: Scientific.
Type of project/Client: Course project.