• Bactrospora corticola (Fr.) Almq.
Bactrospora corticola
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This rare and inconspicuous crustose epiphyte has a mostly grey-white scurfy thallus and small, dense, brown-black discs (to 0.6mm diam.). Making a squash of the disc is beset with problems due to the presence of insoluble granules, so doing this often cracks the slide. The long, narrow spores (50-100 x 2ųm) soon fragment into numerous pieces. Look for it growing in bark fissures on old trees (especially oaks) in sheltered areas of old estate parklands and old woodlands. Scarce: north-eastern Ireland, but also County Mayo.

Key characteristics

  • Scurfy thallus with small black discs; spores break with pressure into rounded or cuboid fragments; mounting the disc in K can crack microscope slide
  • A rare bark fissure lichen of ancient woodland or parkland trees.

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Bactrospora corticola (Fr.) Almq.. [In] LichenIreland. Accessed on 2018-07-23.