wasp nest slime mold

(Metatrichia vesparium)

Conservation Status
wasp nest slime mold
Photo by Luciearl
  IUCN Red List

not listed


not listed


not listed


Wasp nest slime mold is a common and widespread plasmodial slime mold. It is found in Europe, Asia, Africa, Australia, and North and South America. In the United States it is common east of the Great Plains, including Minnesota, less common in the west. It grows in open forests on dead and rotting wood, especially hardwood.

The fruiting body (sporocarp) may be attached directly to the substrate (sessile) or rise in a densely crowded group of up to twelve on a common stalk (stipitate).

The spore-producing structures (sporothecae) are less than (2.5 mm) in height, and about 1 32 (0.4 to 0.7 mm) in diameter. They are almost cylinder-shaped or cone-shaped to almost egg-shaped, and have a distinct convex lid (operculum) on top. The outer skin consists of two or three layers: an outer, tough, cartilaginous, dark red or reddish-purple to nearly black layer; and an inner membranous layer. The operculum is shiny, iridescent, and dark red or reddish-purple to nearly black. When mature, it swings open like a jack-in-the-box, and the interior expands outward. The expanded interior consists of a few fibers (capillitia) interspersed with the spores. The capillitia are very long, coiled, and red. The spore mass is bright red or rust-red. When it dries out, the spores are disbursed by wind. Eventually, the expanded portion disintegrates. What is left looks like the nest of a paper wasp, giving this slime mild its common name.


Similar Species

Habitat and Hosts

Open forests. Dead wood.






Distribution Map



4, 24, 26, 29, 30, 77.




Widespread and common

  Kingdom Protozoa (protozoans)  
  Phylum Mycetozoa (slime molds)  
  Class Myxomycetes (true slime molds)  
  Order Trichiales  
  Family Trichiaceae  





Metatrichia vesparia


Common Names


wasp nest slime mold








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Other Videos
  Wasp Nest Slime Mold, Metatrichia vesparium

Published on Aug 16, 2017

Hey everyone! In today's video I talk a little bit about one of my favorite slime molds, the wasp nest slime mold. Like most myxomycetes, there has been a disappointing lack of research done on this organism, but I tried to provide what I could find both online and in the literature. All photos and illustrations are mine.

Blog: Microcosmia.com
Redbubble: https://www.redbubble.com/people/microcosmicshop
Music: Bensound




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Location: Cass County

wasp nest slime mold  
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Created: 11/12/2018

Last Updated:

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