Slime mold vs. fungi — is slime mold a fungus?
Short answer: no. Slime mold looks moldy and has "mold" in its name, but it isn't a fungus at all. Here's the real difference between slime mold (Physarum) and fungi like Mucor — and why it matters.
Different kingdoms of life
Slime mold and fungi aren't just different species — they're in entirely different kingdoms. Physarum polycephalum is a protist (Amoebozoa): a brainless, single-celled organism that crawls, pulses, and engulfs its food like an amoeba. A fungus like Mucor is in the kingdom Fungi: it grows as a fixed web of thread-like hyphae that absorb nutrients and reproduce with spores.
At a glance
| Slime mold (Physarum) | Fungi (e.g. Mucor) | |
|---|---|---|
| Kingdom | Protist (Amoebozoa) | Fungi |
| Cells | One giant cell, many nuclei | Networks of hyphae |
| Moves? | Yes — actively crawls & explores | No — grows in place |
| Feeds by | Engulfing bacteria & food | Absorbing nutrients |
| Famous for | Solving mazes without a brain | Mycelium, spores, fermentation |
| Speed | Visible movement in hours | Fills a shape over 1–2 days |
Why the confusion?
Both can look like a soft, spreading "mold," both like damp environments, and slime molds were historically classified as fungi long ago. Modern biology moved them into the protists once we understood their amoeba-like behavior. The name stuck; the classification changed.
Why it matters for your kit
Because they behave so differently, they make different kinds of living art:
- Slime mold is dramatic and fast — it moves, reacts, and can be dyed into color. Great for a living, ever-changing pattern. See the Slime Dyeing Kit.
- Fungi (Mucor) grow to fill a shape — which is what FunguyLab's Mycelian Micro uses, guiding growth with light to "print" a designed pattern in living tissue.
Try the living medium yourself.
Grow and dye living slime mold with the FunguyLab Slime Mold Kit — live Physarum culture + food-safe dyes, $39.
Get the Slime Mold Kit →More guides: How to grow slime mold · How to dye slime mold into color