
Limacidae, also known by their common name the keelback slugs, are a taxonomic family of medium-sized to very large, air-breathing land slugs, terrestrial pulmonate gastropod molluscs in the superfamily Limacoidea.
Limacinae are a taxonomic subfamily of air-breathing land slugs, terrestrial pulmonate gastropod molluscs in the family Limacidae.

Bielzia coerulans, commonly known as the Carpathian blue slug or simply the blue slug, is a species of very large land slug, a terrestrial pulmonate gastropod in the family Limacidae, the keelback slugs.

Doratifera vulnerans, commonly known as the mottled cup moth, Australian cup moth or Chinese Junk, is a species of cup moth of the family Limacodidae. The species was first described by John Lewin in 1805 and is the type species of the genus Doratifera. It is found in Australia. It is known for its caterpillar having unique stinging spines or hairs that contains toxins, for which the scientific name is given that means "bearer of gifts of wounds". Chemical and genetic analysis in 2021 show that its caterpillar contains 151 toxins, some of which have medicinal properties.
Lehmannia is a genus of air-breathing land slugs in the family Limacidae, the keelback slugs. The genus is distributed in Europe and North Africa.
Lehmannia marginata is a species of air-breathing land slug, a terrestrial pulmonate gastropod mollusk in the family Limacidae. Sometimes classified in the genus Limax, the species is distinct in its ecology, and its nearly transparent body. It is a medium-sized species, rarely exceeding 12 cm in body length. The body is fairly long and narrow, with a marked keel. The keel looks lighter than the remaining body against the darker innards.
Lehmannia melitensis is a species of air-breathing land slug, a shell-less pulmonate gastropod mollusk in the family Limacidae.

Lehmannia nyctelia is a species of air-breathing land slug, a shell-less pulmonate gastropod mollusk in the family Limacidae.
Limacus is a genus of air-breathing land slugs, terrestrial pulmonate gastropod mollusks in the family Limacidae, the short-keeled slugs.

Limacus flavus, known commonly as the cellar slug, the yellow slug, or the tawny garden slug, is a medium to large species of air-breathing land slug, a terrestrial pulmonate gastropod mollusk in the family Limacidae.
Limacus maculatus, the green cellar slug or Irish yellow slug, is a species of slug native to the Caucasus and Black Sea coast. It has also been introduced to a number of northern European countries and Russia.

Limax is a genus of air-breathing land slugs in the terrestrial pulmonate gastropod mollusk family Limacidae.

Limax cinereoniger is a large species of air-breathing land slug in the terrestrial pulmonate gastropod mollusk family Limacidae, the keelback slugs. This is the largest land slug species in the world.
Limax dacampi is a species of air-breathing land slug, a terrestrial pulmonate gastropod mollusk in the family Limacidae, the keelback slugs.
Limacus maculatus, the green cellar slug or Irish yellow slug, is a species of slug native to the Caucasus and Black Sea coast. It has also been introduced to a number of northern European countries and Russia.
Limax luctuosus is a species of air-breathing land slug, a terrestrial pulmonate gastropod mollusk in the family Limacidae, the keelback slugs. So far, it has not been adequately investigated and is therefore an unsafe species.

Limax maximus, known by the common names great grey slug and leopard slug, is a species of slug in the family Limacidae, the keeled slugs. It is among the largest keeled slugs, Limax cinereoniger being the largest.

Malacolimax is a genus of air-breathing land slugs, terrestrial pulmonate gastropod mollusks in the family Limacidae, the keelback slugs.

Malacolimax tenellus is a species of air-breathing land slug, a shell-less terrestrial gastropod mollusk in the family Limacidae.