Black Slug – Arion ater – Helix aspersa

Black Slug   Scientific Name:  Arion ater Common Name:  Black slug, black arion, European black slug, large black slug Appearance:  Black slug is a unique mollusc without any external shell. It is generally dark black in colour and ranges in size from 4 to 6 inches. Depending upon the latitude, their colour may also be white or grey. It also has long tubercles and produces toxic mucous. Host Plants or Food: Black slugs are omnivores and often act as decomposers through their toxic mucous. It feeds on worms, fungi, leaves, stems, dead plants, and animal dung. Territory: Throughout North America, Europe, Australia, Western USA, Eastern USA Mode of Damage:  It uses its radula to cut the food material into smaller pieces and then coats it in the toxic mucous to digest and decompose. It may be a stem and twig damager as well as damage to other parts of the plant. Habits and Life History: Black slug is widely found in vegetative areas, such as fields and crops. The slugs come out at night, usually in the spring season. Although it prefers mating with a male, it is a hermaphrodite capable of fertilizing itself. After mating, they lay eggs in a moist, dark environment such as grass fields or mosses. A single slug can lay up to 150 eggs; every one to three weeks, which hatch in about 27 days. It is highly resistant to cold; therefore, most hatching and maturation occur during the winter season.