Slime molds have almost no fossil record, which is not surprising. Not only do slime molds produce few resistant structures (except for spores,) but they live in moist terrestrial (land as opposed to water) habitats, such as on decaying wood or fresh cow dung, where they are not likely to be preserved. A few slime mold fossils where found in 1992 in amber.
There are two types of slime molds: cellular and acellular or plasmodial. These are found in forests and sometimes lawns throughout the world. Some acellular species may cover an area of several square feet.
People complain sometimes that the yellow blob of slime mold looks like dog vomit and that the brown powder stains sidewalks. Here�s one example, "Ewwww! There's an orange-yellow slimy blob that seems to be growing in the bark mulch around our shrubs. Almost overnight, it seems to grow from a small patch to a giant thing the size of a bath towel! It's creepy, like some alien creature."
Despite being so ugly and creepy to some people, slime molds are not harmful.
Although Slime molds are the cause of clubroot (also called finger-and-toe,)
a disease of cabbage and other plants in the mustard family.