Mycoacia-fuscoatra-Lionel-Ferry-France

Genus Mycoacia Donk

Mededelingen van de Nederlandse Mycologische Vereeniging 18-20: 150 (1931)

Type: Hydnum fuscoatrum Fr., Novit. Fl. suec.: 39 (1814)

Mycoacia in the broad sense were phlebioid fungi with teeth, and they were separated from other resupinate, toothed fungi by the waxy consistency. The microscopic characters and other traits are close to Phlebia, leading Nakasone (1997) to move four species, including the type Mycoacia fuscoatra, under synonymy with Phlebia, but that broad Phlebia concept was polyphyletic. One clade separate from Phlebia contains Mycoacia fuscoatra and M. nothofagi. The placement of M. aurea is near Lilaceophlebia, while P. uda has moved to the Sarcodontia-Crustodontia clade. The four species below are recorded in the states of Illinois, Indiana, or Wisconsin. All the species are best separated on microscopic characters (see Nakasone 1997). Note that the coloration is variable for the different species. [Colors below in brackets are from Chicago specimens.] Quotes are taken from Nakasone (1997).

  1. Mycoacia aurea, includes M. stenodon (generally orange to brown; does not react to KOH). characterized by slender teeth and abundant, small, allantoid [sausage-shaped] or cylindrical basidiospores with slightly thickened walls. Characters are variable; the spores are typically curved. Cystidia are absent or rare.
  2. Mycoacia fuscoatra [Ours cf.: yellowish-white teeth; dark vinaceous with KOH.] characterized by slender, subulate cystidia [tapering to a point; not encrusted], cylindrical spores, encrusted hyphae in the tooth trama, and reddish brown basidiomata. Spores, (4.5-)5-6 × 2-2.2(-2.5) µm, are narrower than M. uda and M. nothofagi.
  3. Mycoacia nothofagi (variable, brown to orange; light colored specimens turning pinkish red to dark brown in KOH). distinguished by soft, brittle teeth [and] abundant, thick-walled, encrusted cystidia. Fresh specimens have a sharp, sweet odor.
  4. Sarcodontia uda [Ours: bright yellow teeth; dark purple with KOH.] distinguished by basidiomata that turn purple, red or brown in KOH, resinous covered hyphal-end cells in the teeth, short, fusiform cystidia [spindle-shaped; not encrusted], and ellipsoid basidiospores.
Taxonomy:
The genus name Mycoacia Donk replaced the illegitimate name of Acia P. Karsten, which was a later homonym of Acia Schreb. 1791 (Rosaceae). See Nakasone (1997) for discussion of the extensive synonymy of the various species.
Related links:
Floudas D., D.S. Hibbett. 2015. Revisiting the taxonomy of Phanerochaete (Polyporales, Basidiomycota) using a four gene dataset and extensive ITS sampling. Fungal Biology 119(8): 679-719.
Justo, A., O. Miettinen, D. Floudas, B. Ortiz-Santana, E. Sjökvist, D. Lindner, K. Nakasone, T. Niemelä, K.-H. Larsson, L. Ryvarden, D.S. Hibbett, A revised family-level classification of the Polyporales (Basidiomycota), Fungal Biology (2017), doi: 10.1016/j.funbio.2017.05.010.
Karen K. Nakasone. 1997. Studies in Phlebia. Six species with teeth. Sydowia 49(1): 49-79. (PDF)
Taxon links:
18091 MycoBank ; Index Fungorum ; Species Fungorum

Note. Work in the Chicago area is preliminary. We have additional unexamined toothed corticioid specimens.