Meruliopsis taxicola (Pers.) Bondartsev

in Parmasto, Izv. Akad. Nauk Estonsk. S.S.R., Ser. Biol. 8:274 (1959)

wine-red netcrust [suggestion by Leacock]. Many European names.
Epithet = yew-tree dweller. Genus = resembling Merulius.
Annual effused poroid crust, spreading over wide area; up to 4 mm thick. Reddish to dark purple. Margin white, broad, contrasting with pores. Texture tough and waxy when fresh, hard and brittle when dry, somewhat separable. Pores angular, 2 - 4 per mm, tubes with continuous hymenium over the dissepiments. Context white and fibrous, up to 2 mm thick. Microscopic characters: spores allantoid (curved), 4.5–6 × 1–2 µm. Hyphal system monomitic, clamps absent. Cystidia present as subulate smooth cystidioles that are the same size as the basidia.
Similar species:
Gloeoporus dichrous has clamped generative hyphae, cystidioles absent, smaller spores, and occurs on hardwoods. Ceriporia purpurea [group] has a lighter more reddish color, a distinct poroid hymenophore, and longer spores (5-7.5 µm). (Gilbertson and Ryvarden 1986). Ceriporia spissa has bright orange pores when fresh and the pores are very small.
White rot saprobe on conifers, such as pine and spruce, also Douglas fir, hemlock; rarely on aspen (a hardwood). Reported also on birch and gorse in Europe.
Spring, summer, fall, may over-winter.
Circumglobal in boreal coniferous zone and southward with confers. Also in Australia, New Zealand. Collections in southern Illinois were on pine.
Chicago Region status:
No known collections. The only Illinois collection at the Field Museum is Harper's 1908 specimen from River Forest, Illinois, identified as Poria rufa. This Harper collection of 1908 is Ceriporia spissa, which looks very similar but has tiny uniform pores. Duplicates of Harper specimens from 1908 are found at Mich, NY, TENN, UC (and filed under taxicola). Collections of Poria rufa at the Field Museum herbarium were annotated in 1962 to Poria taxicola, then in 1978 to Meruliporia taxicola, then in 2000 to Gloeoporus taxicola. Some of these specimens from other states appear to be M. taxicola (and are on conifer) but some are on hardwood, one on oak, and may not have correct identification.
France. Collected by Chaillet on trunk of Taxus baccata (English yew or common yew).
The species has also been placed in Merulius, Poria, Merulioporia, Ceriporia, and Caloporus.
Regarding Poria rufa: Jung et al. (2018) does not list it as a synonym. Index Fungorum treats it as a synonym while Mycobank does not. J.L. Lowe (1966) lists it as a synonym. Both names are sanctioned by Fries and "rufa" is the older epithet. I don't know why it does not then take priority. Several authors say the type is lost or that there are no specimens at Kew. Donk (1974) lists the taxon as a nomen dubium.
Specimens examined:
Harper collections from 1903 and 1908 at F.
Description links:
Les champignons du Québec (French version of Gilbertson and Ryvarden (1986)).
See descriptions at Mycobank (below).
Related links:
Gilbertson, R.L., L. Ryvarden. 1986. North American Polypores. Volume 1: Abortiporus - Lindtneria. Fungiflora, Oslo, Norway. pp. 1 - 433.
Jung, P. E., H. Lee, S.-H. Wu, T. Hattori, M. Tomšovský, M. Rajchenberg, M. Zhou, Y. W. Lim. 2018. Revision of the taxonomic status of the genus Gloeoporus (Polyporales, Basidiomycota) reveals two new species. Mycological Progress (2018) 9 pp.
Records online:
Mushroom Observer ; MycoPortal
Taxon links:
300911 MycoBank ; Index Fungorum ; Species Fungorum