The Shaggy Ink Cap is a Nematophage

Shaggy Ink Cap, Coprinus comatus

The Shaggy Ink Cap (or Lawyer's Wig, Coprinus comatus) is a large, gregarious basidiomycote fungus that is often collected from the wild and eaten. The fruiting body first appears as an oval structure with no visible stem. The cap is covered with shaggy pale white to brown scales. It pulls away from the stem, turning pink, then black. The cap then dissolves into a black ink-like fluid (Harding et al., 1996 How to Identify Edible Mushrooms p. 54).

Shaggy Ink Cap, Coprinus comatus with cap dissolving

C. comatus was assumed to be an excusively saphrophitic fungus. However, Luo et al. (2004 Mycologia 96 pp. 1218-1224) report on trapping, killing and feeding on two nematode species, the free living Panagrellus redivivus and the root-knot nematode, Meloidogyne arenaria by the fungus. It produces burr-like structures on sporophore-like branches called spiny balls that damage the nematode cuticle leading to leakage of the inner materials of nematodes (Luo et al., 2007 Applied and Environmental Microbiology 73 p. 3916-3923). In addition, C. comatus produces toxins that immobilise the nematodes. Once a nematode has been infected, it is digested and consumed within days. Hyphae then grow out of the nematode.