Serpula himantioides

Names

No English name yet

Serpula himantioides

Description

This fungus is the lesser-known, wild relative of the dreaded dry-rot fungus Serpula lacrymans, which is infamous for destroying poorly ventilated buildings – including houses. Although both species grow on woody material as a source of energy, S. himantioides is primarily found in the wild growing on moist timber of conifers, whereas S. lacrymans is only known from inside buildings. Both species form soft, flat, membranous fan-like fruit bodies (see images). In the case of S. himantioides, this structure is very thin, almost paper-like up to maximum of a few mm thick. The whole structure is rather lightly attached to the woody substrate and readily loses its form when removed. The outer edge of the fruit body is white to cream and smooth but pore-like ridges progressively appear away from the edge and these darken to orange-brown. Microscopically, the fruit body is made up of two types of hyphae: pale thin-walled hyphae and thick-walled brown hyphae (called skeletal hyphae) (see image). The brown coloured spores are produced on the convoluted maze of ridges (see images).

This species was first described in 1818 by one of the godfathers of fungi, Elias Fries, from Sweden under the name of Merulius himantioides. The species was subsequently transferred to Serpula by the Finnish mycologist Karsten in 1884.

Somewhat surprisingly, the genus Serpula belongs to the group of fungi known as the Boletes. This group is much more familiar as the Penny Buns or Ceps, which are highly prized edible fungi.

Fruiting

The fruit bodies are apparently produced all year round with the previous records for Scotland from February and August.

Habitat

Moist conifer timber.

Distribution

The National Biodiversity Network list 255 records for S. himantioides with the great majority being in England (see map below). The fungus appears to be very rare in Scotland with only two records: one from mid-Perthshire in 1985, and the other from Edinburgh in 2003. The substrate for the first find was not given but the other one was growing on a conifer log. NBN Atlas map.

Please remember to submit your records to yourlocal recording group or via the Scottish Fungi online recording form.