Paras is a coconut crab-shaped insectoid creature, with the unique feature of having mushrooms known as tochukaso growing from its back. They grow from spores that are doused on this Pokémon's back at birth by the mushroom on its parent's back. The tochukaso can be removed at any time, although researchers suggest that Paras only do so under extreme measures.

Though tochukaso are parasitic in nature, Paras manages to make use of the mushrooms by creating a semi-symbiotic relationship; the mushrooms draw their nutrients from the host Paras's body in order to grow, and Paras is able to use the mushrooms spores along with its own pincers for self-defense.

Paras may have long life spans, because the tochukaso is known for having properties that are beneficial for longevity.

The mushrooms on Paras's back are often prized by collectors.