Lichens Lecanora conizaeoides

The use of terrestrial invertebrates as sentinel organisms has been suggested for monitoring lead. The spider Araneus umbricatus, for example, contained lead body burdens that correlated with that in a lichen (Lecanora conizaeoides) that is used to monitor atmospheric lead (Clausen 1984). Similarly, the woodlouse (Porcellio scaber) seems to reflect lead concentrations in adjacent soil or leaf litter (Hopkin et al. 1986). 

Figure 16.15 Superhydrophobic surfaces in biology the lichen Lecanora conizaeoides showing high roughness with inset showing water drop 155 4°. (Reprinted with permission from Journal of Plant Physiology, A lichen protected by a super-hydrophobic and breathable structure by N.J. Shirtcliffe, F. B. Pyatt, M.l. Newton and C. McHale, 163, 1193-1197. Copyright (2006) Elsevier Ltd)...

Brightman, F. H. (1964). The distribution of the lichen Lecanora conizaeoides Cromb. in North Ireland. Ir. Natur. J. 14, 258-262. 

Paul, A., Hauck, M. Fritz, E. (2003). Effects of manganese on element distribution and structure in thalli of the epiphytic lichens Hypogymnia physodes and Lecanora conizaeoides. Environmental and Experimental Botany, 50, 113—24. 

France. In 1980 the Pb pollution produced by car exhausts on the adjacent motorway (A6) was assessed by means of several lichen species Cladonia portentosa, Cladonia chlorophaea, Lasallia pustulata, Umbilicaria grisea, H. physodes, P. caperata, Ever-nia prunastri, Lecanora conizaeoides and U. hirta. In 1992 these lichens were found to contain less Pb than twelve years previously. The average figure for all measured species in all sites displayed a similar decrease 3.2-3.S times less. The decrease of Pb fallout along the motorway was ascribed to the consumption of unleaded gasoline. 

Fig. 2. Some changes in the lichen cover of ash trees moving away from Newcastle to the West. E(W), biomass (oven dry weight) of Evernia prunastri E(c), cover of Evernia prunastri L. con.(c), cover of Lecanora conizaeoides, (From Gilbert, 1969.)...

Centers of old industrial towns support very few species and in the areas of highest pollution acid stone and trees remain completely uncolonized. In Britain the only common town lichens are Lecanora dispersa, Candelariella aurella, Lecania erysibe, and a few others, all on asbestos or similar calcareous substrata Lecanora conizaeoides (L. pityrea) on acid stone and tree bases and occasional Cladonia spp. in sheltered localities. These species which show an enhanced resistance to air pollution are of great interest to lichenol-ogists but remain little studied. Figure 2 shows how increases... 

The biggest disparity in temperate latitudes is between cities with and without Lecanora conizaeoides. Where it is well established this lichen is... 

Many problems center around resistant species of which Lecanora conizaeoides is the outstanding example. Its remarkable resistance to SO2 under acid conditions is still unexplained, though it seems likely that a fast growth rate—as this feature is common to all resistant lichens and bryo-phytes—confers a certain advantage. At present there is insufficient evidence to decide whether L. conizaeoides is a recently evolved acidophytic toxitolerant lichen in the process of extending its distribution along well-defined urban invasion paths—hence an apparent connection with pollution —or if it has some nutritional requirement which is satisfied by urban pollution. 

Ahti, T. (1965). Notes on the distribution of Lecanora conizaeoides. Lichenologist 3, 91-92. Almborn, O. (1943). Lavfloran i Botaniska Tradgarden i Lund. Bot. Notis. pp. 167-177. Baddeley, S. M., Ferry, B. W., and Finegan, E. J. (1971). A new method of measuring lichen respiration Response of selected species to temperature, pH and sulfur dioxide. Lichen-ologist 5, 18-25. 

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