Minnesota Seasons - Lobster Mushroom

Conservation • Description • Habitat • Ecology • Distribution • Taxonomy

Conservation Status

IUCN Red List

not listed

NatureServe

not listed

Minnesota

not listed

Description

Lobster Mushroom is a parasitic, mold-like sac fungus. In North America it grows on Peppery Milkcap (Lactarius piperatus), Short-stemmed Russula (Russula brevipes), and possibly other white Lactarius and Russula species. It appears as a bright orange coating on a deformed gill mushroom. When view under a hand lens, the surface appears pimply due to minute, flask-shaped, fruiting bodies. Eventually, it completely covers the stalk (stipe), gills, and cap.

The underground, vegetative part (mycelium) of this fungus grows on the mycelium of the host fungus and fruits at the same time. The bright orange to orangish-red tissue covers the fruiting body of the host before it emerges from the duff. The host mushroom is deformed and often is pitted with debris slightly embedded in the cap. The gills are reduced to blunt, chanterelle-like ridges.

Edible when growing on an edible host. However, the deformed host may be impossible to positively identify.

Similar Species

Habitat and Hosts

Wherever its host species are found

Ecology

Season

July to September

Distribution
		Sources 7, 24, 26, 29, 30, 77. Biodiversity occurrence data published by: Minnesota Biodiversity Atlas (accessed through the Minnesota Biodiversity Atlas Portal, bellatlas.umn.edu, 10/24/2025).
10/24/2025

Occurrence
Common

Taxonomy

Kingdom

Fungi (fungi)

Subkingdom

Dikarya

Phylum

Ascomycota (sac fungi)

Subphylum

Pezizomycotina (sac fungi amd lichens)

Class

Sordariomycetes

Subclass

Hypocreomycetidae

Order

Hypocreales

Family

Hypocreaceae

Genus

Hypomyces

Subordinate Taxa

Synonyms

Hypolyssus lactifluorum

Sphaeria lactifluorum

Common Names

Lobster Mushroom

Glossary

Mycelium

The vegetative part of a fungus; consisting of a mass of branching, thread-like hyphae, through which a fungus absorbs nutrients from its environment; and excluding the fruiting, reproductive structure.

Stipe

A supporting stalk-like structure lacking vascular tissue: in fungi, the stalk supporting the mushroom cap; in ferns, the stalk connecting the blade to the rhizome; in flowering plants, the stalk connecting the flower’s ovary to the receptacle; in orchids; the band connecting the pollina with the viscidium.