Glossary
GLOSSARY
The glossary covers terms used in the descriptive part of the text. Additional information on many of the terms used may be found in Stearn (1992), Wagenitz (1996), Malcolm & Galloway (1997), Kirk et al. (2001) and Dugan (2004).
acicular: needle-shaped, having a sharply pointed apex.
acidophilous: growing on or in conditions of low pH.
acrogenous: formed at the apex.
acute: sharply pointed.
adnate: closely attached, appressed – used of the attachment of fruit to thallus, or of thallus to substratum.
aeruginose: blue-green.
aggregate: clustered (also used for closely related species).
alate: winged.
allantoid: sausage-shaped.
ampliate: enlarged.
amyloid: (of asci, hymenium, ascospores etc.), staining dark-blue or blue-purple in iodine or Meltzer's reagent. A positive amyloid reaction is written as "I+".
ampuliform: flask-like.
anamorph: conidial state of lichenised fungi; phase in the life cycle in which the fungus propagates asexually, generally by production of conidia.
anastomosing: joining up, running into each other – used of branched paraphyses that form a network.
angiocarpic: closed (of an ascocarp) at least until ascospores are mature.
angustate: narrowed.
anisotomic: unequal branching, with a distinct main axis and smaller lateral side branches (esp. in Cladonia).
annellide: a conidiogenous cell that produces a series of ring-like scars at its apex.
annular: ringed.
annulation: ring-like, often pigmented cortical zone, esp. of branches of Usnea sect. Neuropogon.
anticlinal: perpendicular to the surface.
apical: situated at tip.
apiculate: ending in a short, slender, ±flexible projection or apiculus.
apomorphy: derived from (and different from) a generalised condition; used of characters, e.g. apomorphic characters.
apothecium: a ±flat, disc-like fruit, either round (cf. Lecanora) or elongate (cf. Opegrapha) – see also discocarp; pl. apothecia.
appressed: closely and flatly pressed against a surface.
arachnoid: cobwebby.
arcuate: bent, curved or arched.
areola: a small area, rounded, ±polygonal or angular, delimited by cracks or chinks on thallus surface; pl. areolae.
areolate: island-like, sharply divided into areolae by separating cracks.
articulate: jointed.
ascending: directed upwards at a rather narrow angle, curving upwards.
ascocarp: ascus-bearing organ of Ascomycota.
ascogenous: ascus-producing or -supporting.
ascogones (ascogonium): cell or group of cells in Ascomycota fertilised by a sexual process.
ascohymenial: Ascomycota having asci and paraphyses arranged as a hymenium, as in Pyrenomycetes and Discomycetes.
ascolocular: Ascomycota having asci in cavities, as in Loculoascomycetes.
Ascomycota (Ascomycotina, Ascomycetes): class of fungi in which spores are developed in asci.
ascospore: a spore produced in an ascus by "free cell formation". The ascospore wall is multi-layered consisting of an outer perispore, an intermediary layer, the proper wall (epispore) and sometimes an internal endospore.
ascus: sac-like cell of the perfect state of Ascomycota, in which ascospores (usually 8) are produced; pl. asci.
ascyphous: without a cup (cf. Cladonia).
aspicilioid: (of lecanorine apothecia) ±immersed in thallus, at least when young.
attenuate: gradually tapering.
auriculate: ear-shaped.
autonomous: independent, separate.
axis: main stem, or central longitudinal support.
bacill -ar, -iform: rod-like in form.
basidiocarp: basidium-bearing organ (fruiting body) of Basidiomycota.
Basidiomycota (Basidiomycotina, Basidiomycetes): class of fungi in which spores develop on basidia.
basidium: organ in Basidiomycota which, after karyogamy and meiosis, bears the basidiospores; pl. basidia.
biatorine: (of lichen apothecia) of lecideine type, pale or coloured, soft or waxy in consistency.
bifusiform: tapering at both ends.
biguttulate: having two oil droplets.
bilocular: two-celled (of a spore).
bipolar: occurring in both Arctic and Antarctic regions, but widely disjunct to varying degrees at high latitudes and often also at high altitudes between the polar regions, and apparently absent from tropical or equatorial regions.
biseriate: (of an ascus) containing two rows of ascospores.
bitunicate: (of asci) having two functional wall layers, that may or may not rupture or extend at discharge. The term is applied to asci of the Loculoascomycetes. See Jack-in-the-box.
blastidia: small, subsidiary locules in thick-walled spores; also a lichen propagule produced by the budding of thalli in a yeast-like manner (cf. Teloschistaceae).
boreal: pertaining to the northern circumpolar bioclimatic zone, also called the northern coniferous zone or taiga.
botryose: clustered as in grapes.
bullate: with surface puckered, or blistered.
byssoid: cottony, composed of delicate threads, floccose.
caespitose: growing in dense low tufts or cushions.
canaliculate: longitudinally channelled or grooved.
capillary: hair-like.
capitate: have a well-formed head, swollen at apex.
capitulum: globose apical apothecium of Caliciales s. lat., cf. mazedium.
carbonaceous: black, opaque.
cartilaginous: firm and tough but readily bent, gristly.
catathecium: a flattened ascoma, having the wall ±radial in structure, and with a basal plate; pl. catathecia.
catenulate: linked together.
cephalodium: a delimited region within, or a warty, squamulose or fruticose structure on the surface of, a lichen thallus containing a photobiont different to that characteristic of the rest of the thallus. Generally cephalodia contain cyanobionts (e.g. Nostoc) while the rest of the thallus has a green algal photobiont (e.g. Trebouxia). Cyanobionts in cephalodia are important in fixing atmospheric nitrogen. Lichen genera with cephalodia include: Argopsis, Coccotrema, Labyrintha, Lobaria, Nephroma, Peltigera, Pannaria, Placopsis, Psoroma, Psoromidium, Pseudocyphellaria, Solorina, Sphaerophorus, Stereocaulon, and Sticta.
cerebriform: brain-like, convoluted.
chemodeme: group of chemically differentiated individuals of a species, of unknown or of no taxonomic significance.
chlorococcoid: referring to green algae that have a coccoid shape: shaped like a small sphere.
chondroid: tough, cartilaginous.
cilium: a short, eyelash-like hair, usually marginal on fruits or thallus; pl. cilia.
circinate: coiled at the tip.
circumpolar: used of a taxon occurring in a broad latitudinal zone in Arctic and subarctic, or Antarctic and subantarctic regions.
citrine: lemon-yellow.
cladogram: a branching diagram specifying the hierarchical relationships among taxa; the terminal nodes (or taxa) and the internal nodes are defined by apomorphic (derived) characters.
clamp connection: buckle-shaped septum that characterises hyphae of many Basidiomycota.
clathrate: like a network, latticed.
clavarioid: having the appearance of Clavaria.
clavate: club-shaped.
clypeus: a shield-like stromatic growth, with or without host tissue, over one or more ascomata or conidiomata; hence clypeate. Cf. Clypeococcum.
cochleate: shell-like.
complicate: folded, bent upon itself.
concave: hollowed out, basin-like.
concentric: arranged around a common centre.
concolorous: of one or the same colour.
confluent: blending or running together.
congested: crowded.
conglomerate: clustered.
conglutinate: glued or stuck together.
conidioma: specialised multi-hyphal, conidia-bearing structure; pl. conidiomata (also known as pycnidia).
conidiophore: a hypha that bears a conidiogenous cell, or the conidiogenous cell itself.
conidium: specialised non-motile, asexual spore produced in conidiomata; pl. conidia.
contextual: of the tissue lying between the hymenial layer and the upper surface in a basidiocarp.
contiguous: touching but not fused.
continuous: without breaks, uninterrupted.
contorted: twisted.
convex: equally rounded, broadly obtuse.
coralloid: coral-like often brittle (usually of isidia).
coriaceous: leathery.
coronate: crowned (used especially of fruits that are surrounded by lobes of thallus).
corrugate: wrinkled or grooved.
cortex: the outermost layer of the thallus (both upper and lower surface) which, if present, consists of compacted hyphae that may appear either cellular or fibrous.
corticate: having a cortex.
corticolous: growing on bark.
corymbose: arranged in clusters.
costate: veined or ribbed.
crenate: scalloped with small, rounded notches or teeth, the sinuses acute.
crenulate: delicately crenate; with small, rounded teeth, finely scalloped.
crisped: of a margin, crumpled or thrown into waves.
crustose: crust-like, used for lichens having a thallus stretching over and firmly fixed to the substratum by the whole of the lower surface; such thalli generally lack rhizines and a lower cortex.
cryptolecanorine: with a reduced or inapparent thalline margin (of an ascoma).
cuneate: thinner at one end than the other, wedge-shaped.
Cyanobacteria: division of microorganisms comprising the blue-green algae.
cyanobiont: cyanobacterial photosynthetic partner in a lichen symbiosis.
cyphella: a break in the lower cortex of a foliose lichen thallus, which is rounded or ovate or effigurate and in section appears as a cup-like structure lined with a layer of loosely connected, frequently globular cells formed from the medulla; characteristic of the genus Sticta; pl. cyphellae.
cystidium: a sterile body, often of distinctive shape, occurring at any surface of a basidioma (q.v.), particularly the hymenium, from which it frequently projects.
dactyl: small finger-like protuberance from upper surface, often eroding and becoming pustulate.
decorticate: without a cortex.
decumbent: resting on substratum, with ends turned up.
decurrent: descending the stem.
deflexed: bent sharply downwards.
delimited: having a distinct restricting edge or margin.
dendroid: irregularly branched, tree-like.
dense: closely interwoven.
dentate: toothed.
denticulate: delicately toothed.
determinate: having a distinct, defined form.
diaspore: any propagule, asexual or sexual.
dichotomous: branching, often successively, into two ±equal arms.
diffract: cracked into small areas, areolate.
diffuse: widely or loosely spreading, with no distinct boundary or margin.
dimidiate: appearing to lack one half or having one half very much smaller than the other (of a compound ascocarp).
dimorphic: having two forms.
disc: round, plate-like or curved, spore-producing part of fruit body, upper surface of discocarp.
discocarp: ascocarp in which hymenium is uncovered when asci and ascospores are mature, an apothecium.
Discomycetes: class of Ascomycota formerly used for taxa with ascomata that are sessile, open, saucer- or cup-shaped apothecia. The class is not accepted in modern classification, but 'discomycetes' still has utility as a colloquial descriptive term.
discoid: flat and circular, disc-like.
doliiform: barrel-shaped.
dorsal: back or upper surface, surface facing away from the axis.
dorsiventral: with distinct upper and lower surfaces.
disjunct: of a population or taxon widely separated geographically from other populations of the same taxon.
divergent: spreading away from one another, usually at a rather wide angle.
e-: without, or lacking.
echinulate: with spines.
ecorticate: without a cortex.
ectal: of the exterior (cf. ectal excipulum).
effigurate: having a definite form or figure.
effuse: stretched out flat especially as a film-like growth.
ellipsoidal: elliptical in optical section (of spores).
endemic: occurring only in a single, usually small, geographic area.
endoascus: the often extensible inner wall layers of a bitunicate ascus.
endokapylic: a thallus of a lichenicolous fungus in which no morphologically distinct lichenised structure is formed.
endolithic: immersed in rock.
endophloeodal: immersed in bark.
endosubstratic: growing within the substratum.
enteroblastic: (of conidiogenesis) when the inner wall or neither wall of the blastic conidiogenous cell contributes to the formation of the conidium.
entire: having a continuous margin.
epicortex: a thin polysaccharide layer over the surface of the cellular upper cortex in thalli of some foliose lichens (especially Parmeliaceae) and which may have regular pores functioning in gas exchange.
epihymenium: uppermost thin layer (often pigmented) of interwoven hyphae on the surface of the hymenium above asci.
epikapylic: a thallus of a lichenicolous fungus in which a morphologically distinct lichenised structure is formed.
epilithic: growing on surface of rocks or stones.
epinecral layer: a layer of horny dead fungal hyphae with indistinct lumina in or near the cortex and above the photobiont layer.
epiphloeodal: growing on bark.
epiphyllous: growing on the surface (usually upper) of leaves, the mycobiont not penetrating the leaf surface.
epiphyte: a plant growing on an another but not organically connected with it.
epipsamma: granular zone (usually pigmented) permeating upper parts of hymenium but ±distinct from epithecium, especially in Rhizocarpon.
epispore: proper wall of ascus, internal to perispore and external to endospore.
epithecium: upper part of hymenium where this differs in apearance from lower part – layer of uppermost parts of paraphyses overtopping asci, often pigmented.
epruinose: without pruina.
erhizinate: without rhizines.
erose: eroding away upper surface or cortex and exposing inner or medullary layer.
erumpent: bursting through surface.
esorediate: without soredia.
euamyloid: staining blue in iodine.
euseptate: (of conidial septation), having cells separated by multi-layered walls of similar structure to lateral walls.
eutrophicated: nutrient-enriched (correctly of water).
evanescent: soon disappearing, lasting a short time.
exciple: (of an apothecium) tissue or tissues characteristic of the margins adjacent to the hymenium and hypothecium. Proper exciple (excipulum proprium) – tissue at the margin of an apothecium adjacent to the hymenium and hypothecium and inside the thalline exciple when present, without photobiont cells (i.e. non-lichenised). Thalline exciple (excipulum thallinum) – tissue at the margin of an apothecium external to proper exciple and having a structure similar to that of the vegetative thallus with photobiont cells included in it.
excluded: shut out – applied to proper or thalline margin of a discocarp when the disc swells, causing the margin to be obliterated.
exfoliating: losing outer cortex through peeling or cracking.
exsiccatum: dried specimens (of lichens) usually in sets for sale or exchange, or for subscribers, frequently with printed labels and a dated, published schedule (scheda) of contents.
fabiform: bean-shaped.
falcate: sickle-shaped.
falciform: curved like the blade of a scythe or sickle
farinaceous: floury, covered with mealy particles.
farinose: like grains of flour (×10 lens) – of soredia.
fascicle: a close bundle or cluster.
fastigiate: having parallel, massed upright branches (of lichen cortex, made up of parallel hyphae at right angles to axis of thallus).
faveolate: honeycombed, with shallow depressions or lacunae separated by interconnecting ridges.
fenestrate: with open areas or slits.
fibrous: of loosely woven distinct hyphae parallel with long axis of thallus – of cortex.
filamentous: thread-like, composed of filaments.
filiform: thread-like.
fimbriate: fringed, edged, delicately toothed.
fissitunicate: (of an ascus), discharge involving the separation of wall layers.
fissured: cracked, split.
flabellate: fan-shaped.
flaccid: limp, flabby.
flexuous: having a wavy or zigzag form.
foliicolous: living on leaves.
foliole: a small, dorsiventral, leaf-like appendage.
foliose: leaf-like.
friable: readily powdered, crumbling.
fruticose: shrubby, having an upright or hanging thallus.
fungicolous: adapted to parasitism, commensalism or mutualism with other fungi.
furcate: forked.
furfuraceous: scurfy.
fuscous: dusky brown or grey-brown.
fusiform: spindle-like, narrowing at ends, wider in the middle.
gelatinous: rubbery, jelly-like.
geniculate: bent, angled, bent like a knee, often with a subtending spur.
gibbose: with hump-like swellings.
glabrous: without hairs, smooth.
glaucous: having a bluish grey bloom.
glebose: ±rounded elevations of upper surface, blisters.
globose: ±spherical.
glomerule: a very dense cluster, hence glomerulate.
goniocyst: discrete, ±globular structures, c. 12–40 μm diam., ecorticate granules consisting of photobiont cells intertwined and surrounded by short-celled hyphae never protected by an amorphous covering layer – in Micarea.
graminicolous: adapted to parasitism, commensalism, or mutualism with grasses (cf. Lecanora epibryon ssp. broccha).
granular: like grains of sugar (×10 lens).
granule: a grain.
gross: coarse.
guttulate: (of spores) having one or more oil droplets inside.
gymnocarpic: (of a sporocarp) having the hymenium exposed.
gyrose: concentrically folded (of apothecial disc).
halonate: having a transparent coat around it (of the outer layer of spores).
hapter: organ of attachment.
hapteron: an aerial organ of attachment of some fruticose lichens (Alectoria, Bryoria, Usnea) formed by a secondary branch that becomes attached to substratum.
haustorium: a special hyphal branch, especially one within a living cell of the host, for absorption of nutrients.
hemiangiocarpic: (of a sporocarp) opening before quite mature.
heteromerous: having a mycobiont and photobiont components in well-marked layers, with the photobiont in a ±distinct zone between upper cortex and medulla.
heterotypic synonyms: synonyms based on different nomenclatural types (taxonomic synonyms).
hirsute: hairy.
holdfast: a process from the base of the thallus for attachment, often disc-like.
holotype: the one single specimen or other single element used by an author or designated by the author as the nomenclatural type of a taxon.
homoiomerous: having mycobiont and photobiont components intermixed throughout the thallus, not in organised layers.
homonym: a validly published name spelt exactly like another validly published name in the same rank but based on a different nomenclatural type.
homotypic synonyms: synonyms based on the same nomenclatural types (nomenclatural synonyms).
hormocystangium: comprising a few cyanobacterial cells and fungal hyphae; pl. hormocystangia.
humicolous: growing on soil.
hyaline: colourless, translucent.
hygrophanous: having a water-soaked appearance when wet.
hymenium: the spore-bearing layer of a fruit body, containing asci, spores and paraphyses.
hypha: a fungal filament.
hyphidium: a little, or strongly, modified terminal hypha in the hymenium of hymenomycetes.
hypophloeodal: immersed in bark.
hypothallus: a layer of hyphae, often dense and woolly at margins or below thallus, often black or dark-brown, in Anzia, Pannoparmelia and the Pannariaceae.
hypothecium: fungal tissue between hymenium and exciple (if present), often pigmented, also known as subhymenium.
imbricate: overlapping.
immarginate: without a margin or well-defined edge.
immersed: embedded in the substratum (or thallus).
imperforate: not perforated (of an apothecial disc).
impressed: pressed in.
incised: with cuts or tears (usually of a margin).
indeterminate: with margins not well-defined.
indigenous: natural to a country or a region, native.
inflexed: turned or bent inwards (inrolled), used of a margin or a fruit.
innate: sunken, immersed.
inspersed: interpenetrated or sprinkled with granules.
involucrellum: tissue forming the upper part of a perithecioid ascoma (often pigmented or carbonised), surrounding the proper exciple, not involving host or substratum and generally dimidiate.
involute: rolled inwards.
isabelline: dirty brownish-grey, yellowish or tawny – reminiscent of soiled undergarments. The derivation from Isabella (1451–1504), Queen of Castile, consort of Ferdinand of Aragon and patroness of Christopher Columbus, who was reputed to have worn her undergarments for 3 years continuously without changing and washing, is unfounded, but suggests the colour (Stearn 1992: 436).
isidiate: with isidia.
isidium: a corticate, photobiont-containing protuberance or outgrowth of the cortex, that may be warty, cylindrical, clavate, scale-like, coralloid, simple or branched; pl. isidia.
isotomic: branching into two or more branches of equal diameter.
isotype: a duplicate of a holotype, i.e. part of the single collection that includes the holotype.
Jack-in-the-box: type of discharge mechanism found in bitunicate (q.v.) asci, in which the inner wall of the ascus is extruded.
labriform: lip-shaped (usually of soralia).
lacerate: cut or torn, ragged.
lacinia: a ±narrow, linear-elongate lobe of a foliose lichen.
laciniate: deeply, usually irregularly divided into narrow, ±pointed segments.
lacrymoid: tear-shaped.
lacuna: hole, depression, gap.
lageniform: swollen at the base, narrowed at the top.
lamina: a thin, flat organ or part, usually main upper surface of thallus.
laminal: on upper surface.
lateral: at or near edge, especially side or secondary branches.
lax: loosely arranged.
lecanorine: (of an apothecium) with a thalline exciple; with photobiont in margin.
lecideine: (of an apothecium) with a proper exciple only; without photobiont in margin.
lectotype: a type selected from the original elements (specimens or names) on which a taxon was based when the holotype was not designated at the time of publication, or for so long as it is missing.
lenticular: of the shape of a ±circular biconvex lens.
leprose: having the surface dissolved into soredia, loose, powdery.
lichenfield: a vegetation structural class having cover of lichens 20–100%, exceeding that of any other growth form or bare ground (Johnson & Gerbeaux 2004).
lichenicolous: growing on lichens.
lignicolous: growing on decorticated wood (lignum).
lignum: wood, usually of old wood without bark.
limiting: surrounding or setting a limit to – often used of surrounding prothallus.
limbiform: bordered.
linear: very narrow, with parallel margins.
lirella: a discocarp with a long, narrow disc often branching or stellate, cf. Graphis, Phaeographis etc.; pl. lirellae.
lirellate: in the shape of a lirella.
lobate: lobed.
lobe: recognisable but not separated division, especially when rounded.
lobulate: having small lobes.
lobule: small lobe.
locule: cell or cavity.
Loculoascomycete: fungus that produces bitunicate (q.v.) asci within a cavity in a stroma.
longitudinal: lengthways.
lumen: interior of a cell.
macrolichen: larger lichens of squamulose, foliose or fruticose habit (rarely needing microscopic examination for accurate identification).
maculate: spotted or blotched, often caused by discontinuities in photobiont zone below upper cortex.
marginate: with a well-defined edge.
matt: with a dull surface.
mazedium: a spore mass formed in fruits of Caliciales in which spores, generally with sterile elements, become free from asci as a dry, loose, often dark, powdery mass on the fruiting surface.
medulla: loosely arranged layer of hyphae below the upper cortex and photobiont zone.
micareoid: referring to minute, chlorococcoid and closely aggregated algae as commonly found in the lichen genus Micarea, usually occurring as distinct pairs, but rarely forming packets of several small cells.
microlichen: crustose lichen, usually small (commonly needing microscopic examination for accurate identification).
microphylline: with minute leaflets or leafy scales.
mischoblastiomorph: specialised thick-walled spore found in Rinodina.
moniliform: bead-like.
monophyllous: consisting of a single lobe, often undulate or folded.
monophyly (monophyletic group): used of a group that includes all the taxa, and only the taxa, descended from a common ancestor; groups are diagnosed as monophyletic by the presence of synapomorphies.
monopodial: of a stem in which growth is continued by the same apical growing point.
monospecific: having only one representative, of a genus with only one species.
monotypic: having only one representative, of a genus with only one species, or a family with only one genus.
morphodeme: a morphologically differentiated group of individuals of a taxon of undetermined or no taxonomic significance.
multispetate: with many septa.
muriform: like a wall, having transverse and longitudinal septa.
muscicolous: adapted to parasitism, commensalism, or mutualism with mosses; or growing on or among mosses.
mycobiont: the fungal component of a lichen.
nitrophobous: having a preference for habitats/substrata poor in nitrogen.
nubilated: cloudy and semi-opaque as viewed by transmitted light.
obclavate: inversely club-shaped (widest at base).
obligate: restricted to a particular host, substratum or mode of nutrition.
oblique: with sides unequal.
oblong: twice as long as wide and with rounded or truncate ends, margins parallel.
obovate: inversely ovate (narrowest at base).
obpyriform: pear-shaped, with the broad end at the apex.
obsolete: rudimentary or absent.
obtuse: rounded or blunt.
ochraceous: of a dull yellow colour.
omphalodisc: apothecial disc with central column of sterile tissue (in Umbilicaria).
opaque: dull, not translucent.
orbicular: rounded in outline, ±flat.
oriented: turned in one direction.
ostiole: a pore-like opening at the apex of a fruit of a pyrenocarpous lichen through which spores are extruded.
oval: broadly elliptic, narrowing somewhat from middle to rounded ends.
ovate: egg-shaped.
ovoid: of a solid body with an ovate outline.
pallid: pale.
palmate: radiately lobed or divided.
papilla: minute, pimple-like process; pl. papillae.
papillate: with papillae.
paraphyly (paraphyletic group): a category or false group based on the common possession of plesiomorphic characters (symplesiomorphy); a group that does not contain all of the descendants of a common ancestor.
paraphysis: sterile, upright, basally attached fungal filament in a hymenium growing between asci; pl. paraphyses.
paraphysoid network: a network of anastomosing fungal hyphae surrounding asci in some bitunicate lichens and ascolocular ascomycetes, and taking the place of paraphyses.
paraplectenchymatous: of a tissue (paraplectenchyma), composed of cells having isodiametric lumina and unthickened walls.
parasymbiont: an organism symbiotic with a pre-existing symbiosis (e.g. a lichenicolous fungus) not damaging its host.
parathecium: (of apothecia) the outside hyphal layer.
pectinate: comb-like, toothed.
pedicellate: stalked.
pellucid: ±transparent.
peltate: shield-like.
pendulous: hanging down from a support.
percurrent: growing through in the direction of the long axis, as of a conidial germ tube emerging through the hilum or of a proliferation growing through the tip of the conidiogenous cell.
periclinal: curved in the direction of, or parallel to, the surface or the circumference.
periphysis: short, thread-like element inside the neck, near the ostiole, of a perithecium (q.v.) or pseudothecium (q.v.); pl. periphyses.
periphysoids: short hyphae originating above the level of developing asci but not reaching the base of the perithecial cavity.
perispore: sheath outside the true spore wall.
perithecium: ±globular or flask-like fruiting body of Pyrenomycetes and angiocarpic lichens, opening by a pore at top; pl. perithecia.
phialides: conidiogenous cells producing conidia in basipetal succession through one or several openings.
phorophyte: plants on which lichens establish; support or host plant.
photobiont: the photosynthetic partner in the lichen symbiosis, either a green alga or a cyanobacterium.
photophilous: light loving.
photophobous: having a preference for shaded habitats/substrata.
photosymbiodeme: either of one or two morphologically different structures formed by the interaction of a single mycobiont with two different photobionts.
phyllidium: small corticate, scale-like, dorsiventral structure developed at margins or on upper surface of thallus; pl. phyllidia.
phyllocladium: small corticate thalline structure, granular, verrucose, coralloid, squamiform, digitate or foliose outgrowth, containing a green photobiont (in Argopsis and Stereocaulon); pl. phyllocladia.
phylogeny: the history of the evolution of a taxon.
pinnate: compound, with the parts arranged on either side of an axis, as in a feather.
placodioid: crustose at the centre but lobed and plicate at the cirumference.
placodiomorph: a 2-celled spore with a thickened septum that may or may not have a pore, cf. polarilocular.
plectenchyma: a thick tissue formed by hyphae becoming twisted and fused together; paraplectenchyma – with hyphae densely coherent but with large lumina and a cellular appearance; prosoplectenchyma – with thick-walled hyphae having very minute lumina.
plesiomorphy: a generalised character condition shared by all members of a group.
pleurogenous: formed on the side.
plicate: folded in pleats.
plurilocular: many celled.
podetium: lichenised, stem-like portion (stipe or discopodium) bearing the hymenial discs and sometimes conidiomata in a fruticose apothecium [see Hammer 1995a, 1998a, 2001b; Wedin & Döring 1999].
polarilocular (polaribilocular): (of lichen ascospores) 2-celled, the two lumina separated by a thick septum through which a narrow canal passes.
polymorphic: of several forms.
polyphyly (polyphyletic group): a category or false group based on the common possesion of independently derived, but superficially similar, convergent characters (homoplasy); a group that contains taxa of different ancestors.
pore: a small opening.
poriform: pore-like.
porrectulate: directed slightly outwards and forwards.
primary species: species reproducing by sexual means.
procumbent: lying ±flat along the ground or substratum, but not attached or rooting.
proliferating: producing offshoots or outgrowths, successive development of new parts.
propagule: a vegetative fragment capable of propagating a complete new thallus (i.e. isidia, soredia, phyllidia, phyllocladia).
proper exciple: see exciple.
prothallus: weft of fungal hyphae (white, reddish or blue-black) at margins of thallus, without photobiont cells, often projecting beyond thallus onto substratum [see Hammer 1996b].
pruina: frost-like or flour-like surface coating or covering, usually crystalline; pruinose: with pruina.
pseudocyphella: a minute opening (round, elongate, effigurate) in the cortex exposing medullary hyphae (sometimes pigmented) but lacking specialised cells surrounding the cavity. They provide valuable taxonomic characters in several genera, e.g. Bryoria, Parmelia, Pseudocyphellaria; pl. pseudocyphellae.
pseudoparaphysis: a sterile thread inside a pseudothecium (q.v.); pl. pseudoparaphyses.
pseudopodetium: a lichenised podetium-like structure of vegetative origin, ascogonia arising on this not on the preformed granular or squamulose thallus initials (e.g. Cladia, Stereocaulon) [see Wedin & Döring 1999].
pseudostromata: a stroma in which fungal hyphae and remnants of host tissue are mixed.
pseudothecium: an ascostromatic ascoma having asci in numerous unwalled locules; pl. pseudothecia. See Clypeococcum.
psilate: bare, smooth.
pubescent: downy.
pulverulent: powdery.
pulvinate: cushion-shaped.
punctate: marked with very small spots.
punctiform: dot-like.
pustule: a pimple or blister-like swelling, often eroding; pustulate: with pustules.
pycnidium: small, globose or flask-like sporocarp in which conidia are developed; pl. pycnidia.
pyrenocarp: perithecium of pyrenomycete lichens (e.g. Verrucaria).
Pyrenomycetes: class of Ascomycota; used in various senses but commonly for fungi with perithecioid ascomata that are also ascohymenial in ontogeny and have unitunicate asci. Not currently accepted as a taxonomic class, but the term "pyrenomycetes" has value as a colloquial term for all ascomycetes with flask-shaped ascomata.
pyriform: pear-shaped.
radiating: spreading from a central point.
reniform: kidney-shaped.
reticulum: in the form of a network, hence, reticulate.
revolute: rolled outwards on the lower side.
rhizine: organ of attachment, of clustered hyphae; pl. rhizines.
rhizomorph: root-like or string-like aggregation of hyphae with a well-defined apical meristem and commonly differentiated into a rind of small, dark-coloured cells surrounding a central core of elongated colourless cells.
rimose: cracked.
rosette: a rounded form, radiating from a centre.
rugose: wrinkled.
rugulose: delicately wrinkled.
sac: a pouch-like structure; hence saccate: like a sac or bag.
saxicolous: growing on rocks or stones.
scabrid: rough.
scheda: printed, numbered sheet or sheets with cover showing title, author, date and place of publication, and detailing contents of a published exsiccatum. Regarded as a valid publication (see Sayre 1969, 1975; Triebel et al. 2004).
sclerotium: a firm, often rounded, mass of hyphae with or without the addition of host tissue, normally having no spores in it or on it.
scrobiculate: coarsely pitted, faveolate.
scyphiferous: bearing scyphi (cups), used especially when apices of podetia are expanded to form cups (cf. Cladonia fimbriata).
scyphus: an expanded, cup-like structure often terminating a podetium; pl. scyphi.
secondary species: taxon reproducing mainly, or only, by vegetative means, derived from extinct or extant species reproducing mainly, or only by sexual mean (primary species).
septate: divided by cross walls.
septum: cross walls in a hyphae.
seriate: arranged in series.
sessile: not stalked, attached directly to thallus surface (usually of apothecia).
seta: hair-like bristle on a fruiting body; hence setose.
setula: a delicate, hair-like appendage arising from a conidium; hence setulose (q.v.)
setulose: covered with fine bristles or hairs.
simple: not divided into several ±similar parts, contrasted with compound.
sine loco: without data on locality (of a specimen).
sine collectoribus: without data on collector (of a specimen).
sine datum: without date of collection (of a specimen).
sinuous: having rounded angles, wavy (of a margin).
sinus: a re-entering angle or recess, often between two lobes or segments.
soleiform: shaped like the sole of a shoe.
soralium: decorticate area on a lichen thallus where soredia are located; pl. soralia.
sorediate: with soredia.
soredium: decorticate structure comprising photobiont cells and fungal hyphae, having the appearance of a powdery granule and capable of reproducing a lichen vegetatively; pl. soredia.
spathulate: with a gradually widened and flattened blunt end, as a spatula.
spine: a stout process terminated with a sharp point.
spinose: with spines.
spinulose: with minute spines.
spongiostratum: used for hypothallus of Anzia and Pannoparmelia [see Henssen & Dobelmann 1987].
spore: a general term for a reproductive structure in fungi, bacteria and cryptogams, often 1-celled; the analogue of seeds in phanerogams.
sporocarp: spore-producing organ; fruit body.
squama: a scale or scale-like thalli (see Catapyrenium); pl. squamae.
squamiform: scale-like.
squamose: having scales.
squamule: a scale or foliole (usually corticate on both sides), commonly of primary thallus of Cladonia.
squamulose: scaly, with squamules.
squarrose: brush-like, of rhizines, esp. their apices.
stellate: star-shaped.
sterigma: of a basidium (q.v.), an extension of the metabasidium composed of a basal filamentous or inflated part, and an apical spore-bearing projection; pl. sterigmata.
sterigmate: having sterigma.
sterile: not producing spores or a sporocarp.
stipe: portion of the sporocarp (q.v.) that supports the spore-producing structures.
stipitate: stalked.
stria: a fine, longitudinal line or minute ridge, hence, striate; pl. striae.
stroma: mass or matrix of vegetative hyphae (usually black) with or without tissue of the host or substratum, sometimes Sclerotium -like in form, in or on which spores are produced, often covering a group of several ascocarps; pl. stromata.
sub: prefix meaning somewhat, slightly or not quite, e.g. subpedicellate.
submuriform: (of an ascospore), having a small number of vertical and horizontal cross walls.
substratum: the underlying layer; the base to which a lichen is attached.
subulate: tapering from a wide base to a sharp apex, ±circular in cross section, awl-shaped.
superficial: on the surface.
symbiont: an organism that is associated with another in a mutually beneficial relationship.
symbiosis: the living together of unlike organisms in a close, long-lasting association.
sympodial: with lateral branching.
synapomorphy: a derived character, or character state, shared by and defining a group of organisms within the context of a large group.
syntype: one or two or more elements cited by an author in the original place of publication of a taxon when no holotype was designated. A lectotype is generally chosen from one of these elements.
taxon: a taxonomic group of any rank, e.g. family, genus, species, etc.
taxonomy: the science of classification, the arrangement of organisms into a classification.
terete: circular in transverse section, either narrowly cylindrical or tapering.
terminal: borne at the end (of fruits, pycnidia etc.).
terrestrial: on or of the land or earth.
terricolous: growing on the ground.
testaceous: brownish yellow, as of unglazed earthenware.
textura: tissue composed of hyphae, several characteristic types are recognised.
thalline exciple: see exciple.
thalline margin: see exciple.
thalloconidium: a mitosporic propagule produced and seceded directly from the lower cortex and or rhizines of species of Umbilicaria; pl. thalloconidia. Thalloconidia are dark-brown, smooth to roughened with 2–3 wall layers and comprise 1–2500 cells [see Hestmark 1990].
thallus: the vegetative body of a fungus; also used to refer to the entire body of a fungus or lichen.
thelotremoid: having the appearance of Thelotrema, especially of fruits.
tholus: (as in apical) the thickened inner part of the ascus wall in the ascus apex.
thyriothecium: an inverted, flattened ascoma, having the wall ±radial in structure, and lacking a basal plate; pl. thyriothecia.
tomentose: downy.
tomentum: down, of fine, soft, silky hairs.
torus: a thickening or swelling around septum in certain thick-walled spores in Rinodina.
trabeculate: (of paraphysoids) interascal or pre-ascal tissue stretching and coming to resemble pseudoparaphyses; often only remotely septate, anastomosing and very narrow.
translucent: ±transparent.
transverse: across the width.
trebouxioid: similar in appearance or belonging to the photobiont genus Trebouxia, a globose unicellular green alga with a single, central, wavy or stellate chloroplast.
trichotomous: with branches in clusters of three.
truncate: ending abruptly as though with the end cut off.
tubercle: a small, wart-like process.
tuberculate: having tubercles.
tumid: swollen.
turbinate: top-shaped.
turgid: swollen, distended through internal pressure.
type: a nomenclatural type or that constituent element of a taxon to which the name of the taxon is permanently attached.
type species: the species on which the genus is based.
type specimen: the single specimen to which the name of a species or of a taxon below the rank of species is permanently attached.
umbilicate: having an umbilicus, attached at a central point.
umbilicus: a protuberance at the centre, often the point of attachment (see Umbilicaria).
umbo: a central swelling, like the boss at the centre of a shield.
umbonate: having a raised swelling or umbo (q.v.).
unciform: hook-shaped.
uniseriate: in one row (of spores in an ascus).
unitunicate: with one layer (of an ascus that has no inner wall).
urceolate: cup-shaped, urn-shaped, concave, hollow, pitcher-like in form.
vacuolate: cell contents rounded up into one or more vacuoles.
vein: strand of conducting or strengthening tissue (see Peltigera).
ventral: front, or lower surface.
vermiform: worm-like.
verruca: wart or wart-like swelling.
verruciform: wart-like.
verrucose: warted.
verruculose: with small warts.
vesicle: a bladder-like sac.
vesicular: with vesicles.
vicariance: the existence of closely related taxa or biota in disjunct areas that have been separated by the formation of a natural barrier (vicariance event).
vinous: wine coloured.
zonate: ringed (especially at thallus margins) in circular lines forming pale and dark zones.
