Observation 153550: Inonotus hispidus (Bull.) P. Karst.

Found growing on dead Oak that fell one year ago, solitary. Cap surface thick hairy like fuzzy very rough Reddish rust. about 15 cm Pore surface smooth orange staining dark brown to black when bruised. Spore priny rust.

Species Lists


  1. 1 is in KOH
  2. 2 is in sterile water
    1. 1 is in KOH
    2. 2 is in sterile water
    3. Proposed Names

      28% (1)
      Based on chemical features: Flash of red then dark to blackin KOH
      71% (5)
      Recognized by sight
      Used references: Roody
      Based on chemical features: Other species of Inonotus are reported as having black or red-to-black KOH reaction.
      -50% (3)
      Recognized by sight: color, occurrence on oak. those hairs are unusual though… not to mention the reported spore color.
      Based on chemical features: KOH reaction

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      = Observer’s choice
      = Current consensus


      Add Comment
      Spore print rust brown
      By: Eddee (eddeeee)
      2013-11-25 18:34:47 PST (-0800)

      I was able to obtain some spores from the brown stain this left. So I have to say that the spore printis Brown. The spores are roundish as well. I think it is Inonotus hispidus

      Accounts I have read for I. hispidus…
      By: Dave W (Dave W)
      2013-11-25 11:37:19 PST (-0800)

      describe the hairiness as quite variable. Also, the color of the underside is described as variable. However, the rather vivid tones on the underside of this specimen do seem to push the color envelope for this species.

      By: Danny Newman (myxomop)
      2013-11-25 09:12:58 PST (-0800)

      looking unlikely. all but one other observation of I. hispidus on the site (Observation 171355) and most every google image looks completely different from this — especially in terms of color and hairiness — hence my initial doubts.

      micro still welcome.

      By: walt sturgeon (Mycowalt)
      2013-11-25 09:00:29 PST (-0800)

      on the cuticle should be cherry red for H. croceus.

      By: Danny Newman (myxomop)
      2013-11-25 08:49:03 PST (-0800)

      if the deposit on the white cardboard was wet, I suspect it may have been transferred from the bruising reaction. if truly a spore print, it should be dry, powdery, and have the same pattern as the mushroom’s pores. the black cardboard may have been too dark to clearly show the brown color, whatever it came from.

      micro could be quite helpful, if for no other purpose than to determine wither the spores are pigmented or hyaline. these are H. croceus’ micro features:

      Hyphal system monomitic; generative hyphae hyaline. thin-walled. with clamps. throughout the basidiocarp often covered with grains, crystals. and granules of a golden substance. and hyphae often densely agglutinated in this substance, moderately branched. in the context forming some agglutinated cordons of hyphae imbedded in a looser matrix of more branched hyphae, up to 4 µm in diam; in the trama more irregularly organized and up to 6 µm in diam.
      Cystidia or other sterile hymenial elements absent.
      Basidia clayate. 4-sterigmate, 18-30 × 7-10 µm. with a basal clamp.
      Basidiospores broadly ellipsoid. hyaline. thin-walled, smooth. negative in Melzer’s reagent. 4-7 × 3-4.5 µm.

      Rhis is what I did
      By: Eddee (eddeeee)
      2013-11-25 04:58:03 PST (-0800)

      I layed down the speciemen on a white peice of cardbord and a black peice of cardbord. On the white piece there were spots of rust staining spores I assumed. On the black nothing. My scope has been down so I have not been able to us it but good news as of today it is fixed and I still have the speciemen although a bit dried out now. Would Micro pics be helpful?

      are you positive about the spore color?
      By: Danny Newman (myxomop)
      2013-11-24 22:09:48 PST (-0800)

      Created: 2013-11-23 19:10:22 PST (-0800)
      Last modified: 2013-11-25 20:38:51 PST (-0800)
      Viewed: 78 times, last viewed: 2018-09-19 08:31:46 PDT (-0700)
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