Lichen identification

• Spot test | Wikipedia
• General identification tips | British Lichen Society
• Morphology
  • Wikipedia: Foliose,   fruticose,   and crustose, though there are a dozen in total.
  • Foliose, fruticose, and crustose | US Forest Service
  • ▶Crustose, leprose, foliose, fruticose, squamulose, gelatinous, filamentous

Unpolished?:

• https://wgbis.ces.iisc.ac.in/biodiversity/sahyadri_enews/newsletter/issue16/identify.htm
• https://lichenportal.org/portal/index.php
• https://www.waysofenlichenment.net/
• https://www.sharnoffphotos.com/lichen_info/index.html