Cinematic 4K 60 fps. Slug, or land slug, is a common name for any apparently shell-less terrestrial gastropod mollusc. The word slug is also often used as part of the common name of any gastropod mollusc that has no shell, a very reduced shell, or only a small internal shell. A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. Wildlife wild forest ecosystem macro close up plant vegetation swamp, marsh, quicksand, bog, quagmire, habitat morass. UHD 4K 3840X2160.