|Background Info: Lichens rank among the least well known forms of life. Common names, when available, typically apply to the entire genus rather than to individual species. Lichens are generally divided into three basic forms: crustose, or crust-like; foliose or leaf-like; and fruticoseor stalked. Crustose lichens, such as those shown here, are flaky or crust-like. They can be found covering rocks, soil, bark, etc. -- often forming brilliantly colored streaks. Lichens can be divided into three basic forms: crustose, or crust-like; foliose or leaf-like; and fruticoseor stalked. A lichen can literally eat stones, survive severe cold, and remain dormant for long periods without harm.|
Classification of lichens is undergoing change as well. In fact, Mycologists now suggest eliminating the Lichens as a Phylum and, instead, reclassifying each invidual lichen according to its fungal component -- mostly Sac Fungi (Ascomycota). Never-the-less, lichens look so different from other fungi that they deserve separate treatment here.