Leopard Slug

The internal shells of the different species of Limacidae are not recognizable to the species level. Therefore, the fossil distribution of Limax maximus (and other Limacidae species) is unknown. Unidentified calcitic shells of Limacidae are known from European Tertiary and Quaternary deposits.

Limax maximus is nocturnal, feeding at night. It is not very active or prolific. When alarmed, or at rest, this slug merely draws its head within the shield, but does not otherwise contract its body. When irritated, it is said to expand its shield. The homing instinct is strongly developed in this species, which, after its nocturnal rambles or foraging expeditions, usually returns to the particular crevice or chink in which it has established itself. Limax maximus is capable of associative learning, specifically classical conditioning, because it is capable of aversion learning and other types of learning. It can also detect deficiencies in a nutritionally incomplete diet if the essential amino acid methionine is experimentally removed from its food.