Fascinating Lichens of Sri Lanka

Glossary
Entire Without teeth; more or less smooth on the margin
Epruinose Lacking pruina
Exciple The margin around the apothecial disk
176 Fascinating Lichens of Sri Lanka
Acuminate Gradually narrowing to a point, like a spade on a playing card
Adnate Attached tightly to the surface
Alga (Algae) A simple plant composed of a single cell or a string of cells
Apothecium (Apothecia) A disk- or cup-shaped spore-producing organ
Appressed Lying flat or pressed, closely against the substrate
Areolate A lichen thallus that is broken into patches (areoles), often like tiny tiles
Ascus (Asci) Asac-like structure in which spores are formed
Byssoid made up of delicate threads, cotton-like
Cephalodium (Cephalodia) A small growth like gall, containing cyanobacteria, that
occurs in some lichens with green algae as the main photobiont and cyanobacteria as
secondary photobiont
Chemotype A form of a particular species that has distinctive chemistry but is otherwise
the same
Cilia Small hair like appendages on the margins of the thallus or apothecia of many lichens
Concolourous Of the same colour throughout
Cortex The outermost layer of the thallus, which, if present, consists of hyphae which may
appear either cellular or fibrous
Corticolous Growing on bark
Crenate With a scalloped or round-toothed edge
Crenulate having the edge finely toothed with rounded teeth
Crustose Crust-like lichens that are closely attached to their substrate and lack a lower
cortex
Cyanobacterium (Cyanobacteria) Prokaryoticphotosynthesizing organisms that can fix
atmospheric nitrogen and serve as a photobiont in lichen associations (also called bluegreen
algae)
Cyphella (Cyphellae) A round pore in the lower surface of some lichens where medullary
hyphae protrude
Disc The upper surface of a lichen apothecium enclosed by, but not including, the margin
Dorsiventral Flattened, with upper and lower surfaces
Ecorticate Without a cortex and never having had one, cf. decorticate
Endemic Found only in a certain area
Foliose Having leaf-like lobes with distinct upper and lower surfaces
Fruticose A shrubby or hair-like growth form attached only at the base or free growing and
normally with no clearly distinguishable upper and lower surfaces
Globose Globe-shaped
Hypha (Hyphae) Fungal filaments, often modified and resembling round or angular cells
Hypothallus The first and purely fungal (without photobiont) layer upon which an algaecontaining
thallus may develop, sometimes appearing as radiating, branched hyphae or
hyphal bundles, often projecting beyond the thallus onto substrateoften with a distinctive
colour or texture but sometimes merging with the exciple
Imbricate With overlapping layers
Immersed Embedded in the substratum
Isidium (Isidia) Small, asexual reproductive structures on lichens that are minute and
finger-like, covered with a cortex and contain the photobiont
Isidioid Resembling isidia
Isidiate Having isidia
Laminal In the middle, or main part, of the thallus surface, rather than on the margins
Lecanorine An apothecial margin which usually contains a photobiont and often
re¬sembles the thallus, but not the disk, in colour and texture
Lecideine An apothecial margin with no photobiont cells that often resembles the disk,
but not the thallus, in colour and texture
Lichen Composite organism made up of a fungus and an alga, a cyanobacterium, or all
three
Lirella (Lirellae) A type of apothecium that is elongated, sometimes branched
Lobate Bearing lobes
Lobe A flattened branch or projection
Lobulate Having lobules
Lobule Tiny, lobe-like, dorsiventral asexual reproductive outgrowths
Maculate Spotted or blotched
Margin Referring either to the outer edge of foliose or crustose lichen thalli or the outer
boundary of apothecia
Medulla Whitish (rarely orange or yellow) internal layer of most lichens, generally
composed of loosely packed fungal hyphae
Mycobiont The fungal component of a lichen
Fascinating Lichens of Sri Lanka 177