Some Leopard slugs looks as the dark one on the photo, while other have long spots, so they look as a leopard on the skin. A Spanish slug has a plain colour without any spots, and often their head is darker then the body.

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some leopard slugs looks as the dark one on the photo, while other have long spots, so they look as a leopard on the skin. a spanish slug has a plain colour without any spots, and often their head is darker then the body.