Asterophora parasitica

Asterophora parasitica is a wide-ranging parasitic fungus found on decaying fruiting bodies of Lactarius and Russula species in woodlands and forests. It occurs primarily in temperate zones of Europe and North America, with scattered distribution to Costa Rica in Central America. In North America, it is widespread but locally rare, occurring primarily with a bi-coastal distribution. There are over 1500 occurrences, which potentially face threats from logging. Little is known about trends, but with a large range extent and large number of occurrences, abundant habitat, and broad habitat preferences, this species is considered secure.

Asterophora parasitica occurs primarily in temperate zones of Europe and North America, with scattered distribution to Costa Rica in Central America (Castellano 2003, ORBIC 2017). In Europe, it occurs in the United Kingdom, commonly through mainland Europe (including France, Switzerland, and Germany) east to Russia, and in Scandinavia. In North America, it is widespread but locally rare, occurring primarily with a bi-coastal distribution, on the west coast from northern California, United States, north to British Columbia, Canada, and on the east coast from Labrador and Quebec, Canada, south to New England, potentially with scattered distribution in the eastern United States. Range extent was estimated to be almost 80 million square kilometers using specimens and photo-based observations documented between 1994 and 2026 (RARECAT 2025, GBIF 2026, iNaturalist 2026, MycoPortal 2026).

By applying a 1 km separation distance to specimens and photo-based observations documented between 1994 and 2026, it is estimated that there are over 1,500 occurrences rangewide (RARECAT 2025, GBIF 2026, iNaturalist 2026, SEINet 2026).

This species is potentially threatened by logging of forests or woodlands where its hosts live, though there is insufficient data, including anecdotal accounts, to understand scope and severity of threats for this species rangewide.