lecanorales

Lecanorales

Introduction:

The lecanorales is a very diverse order containing about 6000 species. Majority of its

species are lichenized species.

Scientific classification shows;

Kingdom fungi

Division ascomycota

Class Lecanoromycetes

Order Lecanorales

Family Lecanoraceae

The sister group relation of Parmeliaceae (Lecanorales, Ascomycota)

The Parmeliaceae family is possibly the diverse, well-known and most systematically studied

family in the Lecanorales (Ascomycota), comprise 2000 primarily foliose and fruticose lichens

in 89 genera (Eriksson 2006).

LECANORA SPP.:

Life habit:

Lecanora is lichen forming member of order lecanorales. They predominantly form a

symbiotic relationship with algal partner. Occasionally they grow on lichens as a host specific

parasitic fungi so they are termed as lichenicolous.

Thallus:

Thallus is of crustose type. They are usually adnate, having granular structures ,

areolate, placodioid or peltate, and rarely gripped in the substrate.

Apparently the prothallus of Lecanora spp. looks like blackish brown or it may b white to

whitish grey and sometimes it has invisible surface.

Soredia:

Soredia are powdery propagules composed of fungal hyphae wrapped around cyanobacteria or

green algae. Soredia are absent or they may be present.

Isidia and cephalodia:

The vegetative reproductive outgrowth Isidia are absent in the structure of thallus. Cephalodia

are absent on the both upper and lower surfaces.

cortex:

Cortex is present which is rarely composed partly of dead algal cells, or absent.

photobiont:

The primary photobiont is a trebouxioid green alga and the secondary one is absent

Medulla:

Meduula od Lecanora is usually white in color.

Apothecia:

Apothecia are usually immersed, and they are sessile in nature. They are constricted and having

no disc like structure at the base. They are of different colors, epruinose or pruinose margin:

usually containing algal cells, generally conspicuous and concolorous with the thallus, in some

species inconspicuous, reduced or becoming excluded; amphithecial cortex: present or absent

parathecium: hypothecium and subhymenium: hyaline or pigmented; hymenium: hyaline,

strongly amyloid; upper part (epihymenium): usually pigmented, with or without crystals;

paraphyses: simple, septate, usually branched apically, thickened or not thickened apically asci:

clavate, Lecanora-type, 8-spored (or in some non-Sonoran species multispored) ascospores:

simple, narrowly to broadly ellipsoid, smooth-walled, hyaline Conidiomata: pycnidial, immersed

with hyaline to pale brown walls conidia: simple, hyaline, bacilliform, filiform or falcate

Secondary metabolites: atranorin or usnic acids or xanthones, and a wide range of depsides,

depsidones, terpenoids and aliphatic acids Geography: cosmopolitan. Notes: The name Lecanora

comes from the Greek lekanon (a small bowl) and ora (form, beauty), in reference to the

appearance of the apothecia. Lecanora is characterized by asci of the Lecanora-type, simple

hyaline ascospores, and crustose thalli. The apothecial margin usually contains algal cells. It is a

heterogeneous assemblage of different groups, several of which deserve generic rank. Lecanora

s. str. is characterized by the presence of atranorin and oxalate crystals in the amphithecium. In

taxa of Lecanora s. str., presence and size of crystals in the epihymenium and amphithecium and

pigments in the epihymenium are important diagnostic features. The amphithecia present in

Sonoran species include those with small crystals in the algal-containing and cortical part of the

amphithecium or small crystals only in the algal-containing part of the amphithecium (Color

plate 30), and large crystals (Color plate 31). The epihymenia in Sonoran species include: (1)

those with coarse crystals (soluble in concentrated HNO3 [N]), pigmented or not (if pigmented,

pigmentation soluble in K); (2) those lacking crystals, olive green pigmented, (pigmentation

altering to green in K); (3) those lacking crystals, red-brown pigmented, (pigmentation insoluble

in K); and (4) those with small crystals in the epihmenium (insoluble in N), brownish pigmented,

(pigmentation soluble in K). Crystals are best seen in polarized light. Crystals appearing bright in

polarized light are denoted as pol+, while those remaining dark are described as pol-. Also

included in Lecanora is the subgenus Placodium, a heterogeneous group characterized by

rosulate to lobate, squamulose, peltate, or dwarf fruticose thalli, that lack atranorin but have

usnic acids and/or xanthones in the upper cortex, and usually lack oxalate crystals in the

amphithecium. Important diagnostic features include the growth form and thallus anatomy of this

group. In many, but not all Lecanora species the thallus and its associated algae grow around the

fungal apothecial structures forming what is designated the amphithecium (e.g., Brodo 1984). In

the Zahlbruckner school, which has so extensively influenced lichenology, this amphithecium is

often called the thalline exciple. In contrast, 'proper exciple' or 'true exciple' are used to refer to

apothecia lacking a thalline part. Mycologists, dealing with non-lichenized fungi, generally use

exciple to refer to the outermost hyphae of any apothecium. This designation causes confusion

because is not correct for a lecanorine apothecium, where the outermost part is formed by the

thallus. An alternative for "lecanorine" apothecia is to designate the fungal part of an apothecium

as the parathecium. This avoids the confusion about the correct use of exciple. The terms

amphithecium and parathecium have consistently been adopted here, although an alternative

would be to simply use "exciple" for the parathecium.

Lecanora achroa Nyl.

Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2001. Lichen Flora of the Greater Sonoran

Desert Region. Vol 2. Tempe, AZ

Thallus: crustose, continuous or rimose-areolate; prothallus: blackish to bluish brown areoles:

flat, thin, opaque, ecorticate surface: yellowish white to yellowish gray or yellowish green or

pale green to greenish white, smooth, epruinose, with an indistinct margin, esorediate Apothecia:

sessile, 0.3-0.9 mm in diam., lecanorine disc: orange-brown or yellowish brown, plane or

convex, epruinose or slightly whitish gray pruinose margin: concolorous with thallus, thin or

thick, persistent or becoming excluded, even, not flexuose, smooth, entire or verruculose,

without a parathecial ring amphithecium: present, with numerous algal cells, with large crystals

insoluble in K, corticate; cortex: distinct, basally not thickened, interspersed with numerous

small crystals, hyaline, (15-)25-35(-40) µm thick laterally, (15-)25-35(-40) µm thick basally

parathecium: hyaline, containing small crystals insoluble in K epihymenium: yellowish brown to

orange-brown, with pigment dissolving in K, with crystals dissolving in K hymenium: hyaline,

clear; paraphyses: sparingly branched and slightly thickened (up to 2.5 µm wide) apically, not

pigmented; subhymenium: hyaline, 15-20 µm thick; hypothecium: hyaline, without oil droplets

asci: clavate, 8-spored ascospores: hyaline, simple, ellipsoid or broadly ellipsoid, 10.5-16.5 x

6.5-8.5 µm; wall: less than 1 µm thick Pycnidia: not observed Spot tests: K+ yellow, C- or C+

orange, P+ pale yellow Secondary metabolites: arthothelin (minor or absent), atranorin

(submajor), chloroatranorin (minor), 2'-O-methylperlatolic acid (major), usnic acid (major) and

traces of unidentified terpenes. Substrate and ecology: on the bark of deciduous trees World

distribution: pantropical occurring in North, Central and South America, Indian Ocean islands,

Australia, north island of New Zealand, Papua New Guinea and the South Pacific Sonoran

distribution: Baja California Sur and Sinaloa. Notes: Lecanora achroa is characterized by the

comparatively small apothecia with orange-brown disc, the small ascospores, and the presence of

usnic acid. It is similar to L. helva and L. leprosa, but readily distinguished by the different

chemistry.

Lecanora albella (Pers.) Ach.



Thallus: crustose, continuous or rimose-areolate; prothallus: white areoles: flat, thin, opaque,

ecorticate surface: yellowish white to yellowish gray or whitish gray to gray or pale green to

greenish white, smooth, epruinose, with an indistinct margin, esorediate Apothecia: sessile, 0.3-

1.5 mm in diam., lecanorine disc: yellowish brown or pale pink to carneous, plane or convex,

heavily whitish gray pruinose margin: concolorous with thallus, thin or thick, persistent, even or

prominent, entire or flexuose, smooth, entire, without a parathecial ring amphithecium: present,

hyaline to pale yellow, with numerous algal cells, with numerous small crystals that dissolve in

K, corticate or not; cortex: absent or indistinct, basally not thickened, interspersed, hyaline to

pale yellow, (65-)70-100(-120) µm thick laterally, (80-)100-110(-130) µm thick basally

parathecium: hyaline, lacking crystals epihymenium: brown to dark brown, with pigment

dissolving in K, with crystals dissolving in K hymenium: hyaline, clear; paraphyses: slightly

thickened (up to 2.5 µm wide) apically, not pigmented; subhymenium: hyaline, 15-20 µm thick;

hypothecium: hyaline, without oil droplets asci: clavate, 8-spored ascospores: hyaline, simple,

ellipsoid or broadly ellipsoid, (8.5-)11.5-13.5(-14) x (5-)7-8.5(-9) µm; wall: less than 1 µm thick

Pycnidia: not observed Spot tests: K+ yellow or + yellow turning red, C-, KC-, P+ orange to red

Secondary metabolites: atranorin (major), chloroatranorin (minor), connorstictic acid (minor or

absent), conprotocetraric acid (minor), consalazinic acid (minor or absent), constictic acid (minor

or absent), norstictic acid (major or absent), protocetraric acid (major), salazinic acid (major or

absent), stictic acid (major), virensic acid (major, minor or absent). Substrate and ecology: on the

bark of deciduous trees and conifers World distribution: widespread in temperate to boreal

regions of the Holarctic, including Africa, Asia, Europe, and North America Sonoran

distribution: Arizona, Chihuahua, and southern California, rare at elevations above 1500 m.

Notes: Lecanora albella is readily distinguished by its heavily pruinose apothecial disc, relatively

small apothecia with thin margins, and the presence of protocetraric acid. Other corticolous

species with heavily pruinose disc in the area are L. caesiorubella and L. casuarinophila. The

latter species differs in having a leprose thallus and lacking depsidones. L. caesiorubella is very

similar to L. albella and the separation of the two species may become difficult in some cases.

Chemically, the two species are indistinguishable, but L. caesiorubella generally has larger

apothecia and a thicker pseudocortex.

Lecanora arenisaxicola B.D. Ryan & T.H. Nash Go to Parent



Thallus: placodioid, forming +flattened rosettes 0.5-1(1.5) mm across, 1.5 mm thick centrally,

tightly adnate throughout, areolate, rosulate; prothallus: absent areoles: contiguous, 0.2-0.5 mm

across lobes: contiguous but discrete, +distinctly elongated, up to 1 mm long, 0.2-0.5(-1) mm

wide, crenate to incised, +convex; edges not differentiated; tips dropping off abruptly to the

substrate upper surface: pale greenish yellow, appearing yellowish white (to blue or gray tinged

when parasitized), densely pruinose throughout, less so near lobe tips, which become rimose,

esorediate upper cortex: +with dead algal cells, 100 µm thick, the upper 65 µm inspersed with

grayish granules (insoluble in K) in addition to yellow-brown granules (insoluble in K) medulla:

filled with gray granules (pol+, partly soluble in K) throughout; algal layer: +continuous, 65-75

µm thick lower surface: white near lobe tips, otherwise not visible lower cortex: absent

Apothecia: common in thallus center, 0.5-1 mm in diam., sessile, soon constricted at base disc:

yellowish to orangish brown, dull, uniform in color, +plane, epruinose margin: concolorous with

thallus, 0.1-0.2(-0.3) mm wide, raised then level, soon strongly crenate towards the inside,

persistent, with a +gray-green parathecial ring amphithecium: present, with an interrupted algal

layer marginally and extending below the hypothecium, with loosely arranged medulla

composed of branched and anastomosing hyphae c. 2.5 µm wide and with elongated lumina 0.5-

1 µm wide (boundaries of both very distinct), and with fine hyaline granules (insoluble in K) in

places, corticate; cortex: composed of radiating hyphae with roundish cells 4-5 µm in diam. and

inspersed with yellow-brown granules (partly soluble in K) along the walls, and with grayish

granules (pol+, insoluble in K), c. 60 µm thick parathecium: +hyaline, with strongly

conglutinate, periclinal hyphae c. 3 µm wide and with narrow (1-1.5 µm), elongated lumina

epihymenium: inspersed with yellow-brown granules (partly soluble in K), with c. 7.5 µm

superficial uninspersed layer, c. 20 µm thick hymenium: hyaline, c. 65 µm tall; paraphyses:

strongly conglutinate, indistinct even in K; tips (in K) 3-4 µm, hyaline; subhymenium: indistinct;

hypothecium: with randomly oriented to vertically oriented hyphae and fine, hyaline granules

insoluble in K asci: clavate, 40 x 15 µm, 8-spored ascospores: hyaline, simple, ellipsoid to

broadly ellipsoid, (5-)7.5-10 x 4-6 µm Pycnidia: immersed, the ostioles flush with the thallus,

concolorous with the apothecial discs; conidiophores: type III of Vobis (1980), branched once or

twice near apex, the basal cells 10-15 x 3-5 µm conidia: filiform, 10-17 µm long Spot tests:

thallus K-, C-, KC, P- Secondary metabolites: cortex with usnic acid; medulla with roccellic

acid. Substrate and ecology: on gentle to vertical N-faces towards tops of large sandstone

outcrops, in grassland, 1975 m; associated lichens include Lecanora valesiaca (var. valesiaca and

var. sibirica) and Acarospora heufleriana, which are both very abundant in the area World and

Sonoran distribution: Arizona, Coconino Co., known only from the the region around Meteor

Crater. Notes: Lecanora arenisaxicola belongs to section Pruiniferae s. lato of the subg.

Placodium and differs from L. valesiaca, with which it grows side by side at the type locality, by

the following features: thallus thickerareoles distinctly convex; lobes +convex, with level edges

and tips sharply set off from the substrate (dropping off abruptly); upper surface becoming

rimose and more weakly pruinose towards the lobe tips; apothecia rather sparse, soon constricted

sessile, with thicker margins soon strongly crenate towards the inside; cortex of thallus and

apothecia thicker, +with dead algal cells. It differs from L. kofae and L. neodegelii in having

shorter and narrower lobes, thicker cortex and algal layer, and from L. phaedrophthalma in

having smaller apothecia with plane, uniformly colored discs, and it differs from all of these

species in having a densely pruinose upper surface with grayish granules (insoluble in K) within

the cortex. It comes closest to the central Asian species Lecanora usbekica Poelt, but differs

especially in that the thallus center is verrucose-areolate (rather than rimose-areolate), the

apothecial margins are soon strongly crenate towards the inside, and the cortex of the thallus and

apothecia is thicker.

Lecanora bipruinosa Fink Go to Parent



Thallus: placodioid, up to 3 cm wide, 1-2 mm thick, thinning towards margins, rosetted, closely

to somewhat loosely attached, rimose-areolate to verrucose-areolate or subsquamulose;

prothallus: absent areoles: 0.7-1.5(-2) mm, roundish to somewhat crenate or partly angular, plane

to +convex lobes: distinct, contiguous to discrete, usually elongated, (1.5-)2-3(-4) mm long, 0.5-

1.5 mm wide, 0.3-0.5 mm thick, thinner towards tips, plane to convex, transversely +broken-

furrowed, weakly incised to branched, the ultimate segments c. 0.5 mm wide; edges: appressed,

entire to irregularly and coarsely undulate-crenate and +raised or thickened (as in L. muralis)

upper surface: mainly smooth and continuous, to shallowly rimulose, often slightly bumpy or

foveolate near tips of lobes, dull to (especially towards lobe tips and on darkened edges)

+distinctly glossy, usually spotted with fine white pruina, usually pale yellowish green to

moderate or grayish greenish yellow, slowly turning pale yellow or finally pale brown, areas near

tips and edges often blue-green; edges: concolorous with the rest or often paler, but usually not

pruinose; extreme lobe tips: sometimes narrowly blackened, without thallospores, esorediate

upper cortex: without dead algal cells, 50-70 µm thick; hyphae: +anticlinal, thin-walled, 3-4 µm

wide, the lumina 3-5 x 2-3 µm; epinecral layer: 10-30 µm thick medulla: dense, to rather loose in

lower part; hyphae: randomly oriented; algal layer: +continuous lower surface: pale brownish,

often mottled greenish or bluish black lower cortex: absent Apothecia: borne submarginally, 1-

3(-5) per areole, 0.5-2 mm in diam., scattered to crowded, soon sessile and constricted disc:

yellowish brown (to pale orange or green) under +dense yellow pruina, otherwise appearing pale

greenish yellow to pale green, gray, or brown, unchanged when wet. plane or slightly convex

margin: 0.1-0.2(-0.3) mm wide, entire to flexuous, or cracked-crenate from outside, raised then

level, partly almost disappearing, flat-topped to rather convex; concolorous with thallus, spottily

pruinose in outer part, without a parathecial ring amphithecium: present, with a continuous to

somewhat interrupted algal layer densely filling apothecial margin and extending below the

hypothecium, with a rather loose medulla containing fine granules soluble in K, corticate; cortex:

similar to that of thallus, 30-50 µm thick parathecium: up to 30 µm thick laterally and up to 70

µm thick below hypothecium, with hyphae partly or completely oriented periclinally to the

hymenium, the lumina +round to short and irregular and c. 5 x 2-3 µm epihymenium: with layer

of superficial yellow-brown granules (soluble in K) hymenium: 50-65 µm tall; paraphyses:

coherent; tips: 2.5-3 µm wide, scarcely colored; subhymenium: hyaline, 30-50 µm thick;

hypothecium: 75-100 µm; hyphae: randomly oriented to partly vertically oriented, strongly

conglutinate, the lumina often unstained, +elongated, 3-5 x 0.1-0.2 µm asci: broadly clavate, 8-

spored ascospores: hyaline, simple, ellipsoid to narrowly ellipsoid, ovoid or fusiform, 10-12(-14)

x (4-)5-6(-7.5) µm Pycnidia: usually common, immersed; ostioles pale; conidiophores: type III

of Vobis (1980) conidia: mostly 25-35 µm long Spot tests: thallus K-, C-; cortex KC+ yellow,

P-; medulla KC-, P+ yellow or P- Secondary metabolites: cortex with usnic acid; medulla with

psoromic acid or fatty acids (murolic acid complex, with neodihydromurolic acid major).

Substrate and ecology: on volcanic tuff, basalt, rhyolite, or sedimentary rocks, often with a thin

coating of calcareous dust, frequently on shaded, north-facing surfaces, from desert scrub to

woodlands World distribution: SW U.S.A. and NW Mexico, south through the Sierra Madre

Occidental to central Mexico Sonoran distribution: Arizona, California, Baja California,

Chihuahua and Sonora, (200-)610-1040 m. Notes: Lecanora bipruinosa differs from L.

novomexicana by having: 1) shorter, straighter and flatter (not sinuous or plicate) lobes, often

with partly thickened edges, + pruinose upper surface; 2) upper cortex with few or no dead algal

cells, hyphae densely packed, partly forming anticlinal bundles, with larger, shorter and rounded

lumina; 3) apothecial margins often 0.3 mm or more wide and rather flat-topped; and 4)

occurrence in desert areas, mostly below 100 m and 30'N. Material from Arizona often has rather

short and broad lobes with thickened margins (resembling those of L. nashii; see under that

species for further comparisons). Occasional psoromic acid-deficient specimens from Sonora

have very narrow lobes with a +epruinose, dark bluish-green upper surface. Thalli and discs are

often parasitized by with small black ascocarps, 0.05-0.1 mm in diam., of Stigmidium sp. and

Cercidospora spp. (determined by J. Hafellner).

lecanorales

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