Menegazzia A.Massal.

Lichens (1985) - Flora of New Zealand Lichens

MENEGAZZIA Massal., 1854

* Account prepared by P.W. James (BM).

Thallus foliose, dorsiventral, heteromerous, lobate, ± radiate, corticolous, saxicolous or terricolous, rosette-forming to irregularly spreading, loosely to closely attached. Lobes ± inflated, hollow, upper surface corticate, perforate (two species lack perforations), with or without soredia, isidia or maculae, lower surface corticate, naked, ± uniformly attached to substrate, uneven, blackened, without rhizines, walls of internal cavity white, or pigmented or blackened. Apothecia laminal, rounded, lecanorine, often cupuliform, sessile or ± subpedicellate to distinctly pedicellate, disc concave to plane, matt, shining or pruinose, eperforate, thalline exciple well-developed. Epithecium pigmented, occasionally with granular inclusions. Hymenium colourless. Hypothecium chondroid, of thick-walled, conglutinated cells. Paraphyses anastomosing, apical cells capitate or not, ± pigmented. Asci 2- or 8-spored. Ascospores colourless, simple, ellipsoid, 20-120 × 10-50 µm, thick-walled. Pycnidia immersed, minute, punctiform, laminal, with a dark apex. Conidia short, bacilliform. Taxa in the genus show a diverse chemistry, including depsides, depsidones, fatty acids and pigments.

Key

Isidiate or sorediate, apothecia rare or absent

Without isidia or soredia, apothecia often present

Thallus without laminal perforations, isidiate, isidia elongate and ± spathulate, often decumbent

eperforata

Laminal perforations sparse to numerous, sorediate

Thallus yellow-green (usnic acid), soralia vesicular, medulla C+ red

globulifera

Thallus grey, green or brown, without usnic acid, soralia not vesicular, medulla C-

Thallus dark olive-brown, soralia irregular, coarse, pustular, soredia granular

castanea

Thallus pale grey or green, soralia regular, soredia fine, powdery

Lobes narrow (0.5-0.8 mm wide), lobe ends ± white-maculate, soralia granular, developed along edges of laminal, ruptured, blister-like vesicles

nothofagi

Lobes wider than 1 mm, lobe ends not, or indistinctly white-maculate, soralia superficial, not developing from edges of blister-like vesicles

Medulla UV+ vivid ice-blue, Pd-, KC+ pink

ultralucens

Medulla UV- or + orange, Pd+ orange, KC+ orange

Upper side of medulla pigmented ± ochre-yellow, UV+ orange, ends of lobes faintly white-maculate

caliginosa

Upper side of medulla white, UV-, ends of lobes emaculate

Soralia strictly arising from edges of perforations

circumsorediata

Soralia not associated with perforations

subpertusa

Saxicolous or terricolous-muscicolous

Corticolous

Saxicolous, closely appressed, lobes regularly rosette-forming, thallus dark brown-black or olive-greenish

aeneofusca

Terricolous or muscicolous, entangled in basal branches of subalpine shrubs or tussocks, loosely attached, straggling, irregularly branched and entangled, tubular, terete, inflated, thallus white or ± spotted or banded black

inflata

Margins of apothecia bright orange-red (K+ purple-black), medulla K+ red (crystals)

pulchra

Margins of apothecia brown or concolorous with thallus, never orange-red, medulla K+ orange (no crystals) or K-

Upper side of medullary cavity yellow or ochre-yellow, UV+ yellow or orange, spores 8 per ascus

Upper side of medullary cavity not pigmented, UV-, spores 2 or 8 per ascus

Upper side of medullary cavity ochre-yellow, UV+ orange, lobe ends ± faintly white-maculate

foraminulosa

Upper side of medullary cavity yellow, UV+ yellow, lobe ends uniformly grey

pertransita

Medulla UV+ ice-blue, KC+ pink, spores 2

lucens

Medulla UV-, KC+ yellow-orange or -, spores 2 or 8

Apothecia, at least when young, with white-pruinose discs, medulla K+ yellow, Pd+ yellow

dielsii

Apothecia epruinose, medulla K+ yellow → orange or -, Pd+ yellow → orange or -

Apothecia ± pedicellate, exciple scabrid, perforations often large (to 1.5 mm diam.), gaping, margins involute, medulla K-, Pd-

pertransita

Apothecia sessile to subpedicellate, exciple smooth, perforations < 1 mm diam., medulla K+ yellow → orange, Pd+ orange

Thallus congested-convolute, dark red-brown, perforations depressed

testacea

Thallus swollen, often almost terete, not congested, lobes often zig-zag radiating, greenish or green-grey, perforations conical

aucklandica

Menegazzia is primarily a Southern Hemisphere genus (only one species, M. terebrata, is widely distributed in the Northern Hemisphere) of c. 45 species, possibly to be included in the family Hypogymniaceae [Elix Brunonia 2: 176 (1980)]. New Zealand is a predominant centre of speciation in the genus with at least 22 species, 17 of which are discussed here. South-eastern Australia, Tasmania and southern Chile are other areas rich in species of Menegazzia. In New Zealand, species are best developed in Nothofagus forest, and range from North Auckland to the Subantarctic Is, and from s.l. to subalpine rocks at 2000 m. Species are mainly corticolous but one species grows in subalpine grasslands and several on lowland to subalpine rocks. South American species are discussed by Santesson [ Ark. Bot. 30A (3): 1-35 (1942)] who also gives much useful information on the genus. New Zealand species are described by Krempelhuber [ Verhandl. zool.-bot. Ges. Wien 26: 451 (1876)]; Stirton [ Proc. phil. Soc. Glasg. 10: 294 (1877); Scott. Nat. 4: 253 (1878); T.N.Z.I. 32: 78 (1900)]; Hillmann [ Feddes Repert. 49: 38 (1940)]; Zahlbruckner [ Denkschr. Akad. Wiss. Wien math.-naturwiss. Kl. 104: 359-361 (1941)] and James and Galloway (in prep.).

Menegazzia A.Massal.

Key

Volume contents

Share