Physarum polycephalum

slime mold

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

June 17, 2026

Quick Summary

Physarum polycephalum is a notable species within the genus Physarum, which comprises about 20 percent of the species in the phylum Mycetozoa, commonly known as true slime molds. Slime molds are primitive organisms with true nuclei, exhibiting characteristics of both protozoan protists and fungi.12

The vegetative phase of Physarum involves a plasmodium, a mobile, multinucleate mass of cytoplasm without a cell wall. This plasmodium moves across substrates, feeding on bacteria and organic matter. Physarum polycephalum is widely used in physiological experiments, particularly concerning protoplasmic streaming and nuclear behavior. While Physarum cinereum can appear unsightly on lawns, it is harmless.341

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

6 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

Physarum
Physarum polycephalum, a fast-growing species, is the most notable; it has been used widely in physiological experiments in protoplasmic streaming and nuclear behaviour. Physarum cinereum, which forms an ashy-gray coating on lawn grasses under special conditions of moisture and humidity, is unsightly but harmless and…
Read More
Physarum polycephalum, a fast-growing species, is the most notable; it has been used widely in physiological experiments in protoplasmic streaming and nuclear behaviour. Physarum cinereum, which forms an ashy-gray coating on lawn grasses under special conditions of moisture and humidity, is unsightly but harmless and…
Read More