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Leopard slug

Limax Maximus


Limax maximus (literally, "great slug"), also known by common names such as the great grey slug, or the leopard slug, is one of the largest kinds of keeled air-breathing land slug in the world, (Limax cinereoniger being the largest). It is in the family Limacidae, the keeled slugs. Limax maximus is the type species of the genus Limax. The adult slug measures 10-20 cm (4-8 in) in length and is generally a light greyish or grey-brown with darker spots and blotches, although the coloration and exact patterning of the body of this slug species is quite variable. This species has a very unusual and distinctive mating method, where the pair of slugs use a thick thread of mucus to hang suspended in the air from a tree branch or other structure The body length of adults of this slug species is 10-20 cm (4-8 in).[3] The greater part of the body is rounded, but there is a short keel on its tail, with about 48 longitudinal rows of elongate, detached tubercles.[4] The animal's body color is pale-grey, ash-colored, brownish or sometimes yellowish-white. The body is longitudinally streaked or spotted with black. The shield is always black-spotted. The sole of the foot is ash or yellowish-ash colored, and the color is always uniform. The foot-fringe is pale, with a row of minute submarginal blackish tubercles


Although native to Europe, this species has been accidentally introduced to many other parts of the world


spotted in my backyard ,a month ago,it seems like a parasite or a injury infected,i dont realy know,it's very unusual,first time we saw this

No species ID suggestions


AntónioGinjaGinja 5 years ago

thanks Emma ,Ricardo and Maria.
great info Emma,i dont know what it means"Keel" but i remarked several times that they have some diferent body texture,like a shell some times, in a zone near the tail,one time we spotted one with( if you remember )a thing like a cyst,that we thougth was a parasite in that zone ,maybee is natural and can have several formes and textures ,i'll research to.
to us sluggs are awesome as you can notice by the enoumerous sluggs spotting that we maked :)so to honour our lovely sluggs i'am going to post one making a meal with a old bread piece she found in my backyard :)

Hema Shah
Hema Shah 5 years ago

The greater part of the body is rounded, but there is a short keel on its tail, with about 48 longitudinal rows of elongate, detached tubercles.
What does "keel" mean?

Maria dB
Maria dB 5 years ago

Nice spotting; I think I just photographed a similar one. This has been an educational posting; thanks, Antonio and Emma!

Ricardo Salgueiro
Ricardo Salgueiro 5 years ago

Nice point Emma. I'll start to see the slugs in a more friendly way :)

Hema Shah
Hema Shah 5 years ago

"Slugs may seem slimy and horrible to us, but we need them just as much as we need cows for milk or chickens for eggs." While many people think that the removal of the land slug species form the earth would be beneficial, the disappearance of slugs would have a negative impact on humans. In addition to making up the biodiversity of this world, slugs play important roles in the ecosystem that directly impact humans. For example, if the slug did not perform its important role as a decomposer, there would be a domino effect which would reach humans. As Karl Studenroth explains "nutrients would be locked up in dead organisms longer and unavailable to living organisms [without the slug's presence]." This "locking up of nutrients" would effect the fertileness of soil. Fertile soil is very important to human existence, as Tina Teearu states, "at the end of the end, absolutely everything we humans eat can be tracked back to soil." While gardeners and farmers may think that the disappearance of slugs would improve their gardens and crops from being destroyed by the pesky slug, they are wrong. If slugs were to become extinct, soils would be less fertile and, as William H. Amos states, "other species would be obliged to compensate for their absence." Meaning, other organisms deemed as "pests" would fill in for the slugs

Hema Shah
Hema Shah 5 years ago

"In ecosystems they [slugs] are important in breaking down decomposing materials faster and helping to release nutrients back into the overall system quicker" . Without slugs recycling decaying and fecal matter, soils would lose important nutrients, thus plants and crops would not grow as well. This, of course, would create a domino effect, affecting the entire ecosystem and food web of organisms.

Hema Shah
Hema Shah 5 years ago

I will do some research and let yo know soon.
Could be a cyst caused by parasites or a tumor?

Braga, Portugal

Lat: 41.55, Long: -8.42

Spotted on Jun 5, 2012
Submitted on Jul 14, 2012

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