Menegazzia | |
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Menegazzia pertransita growing on a tree near Arthur's Pass, New Zealand. Scale bar = 1 cm. | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Fungi |
Division: | Ascomycota |
Class: | Lecanoromycetes |
Order: | Lecanorales |
Family: | Parmeliaceae |
Genus: | Menegazzia A.Massal. (1854) |
Type species | |
Menegazzia terebrata A.Massal. (1854) | |
Subgenera | |
Dispora R.Sant. (1942) Contents |
Menegazzia is a genus of lichenized fungi containing roughly 70 accepted species. [1] The group is sometimes referred to as the tree flutes, honeycombed lichens, or hole-punch lichens. The most obvious morphological feature of the genus is the distinctive perforations spread across the upper side of the thallus. This makes the group easy to recognise, even for those not particularly familiar with lichen identification.
The genus has a sub-cosmopolitan distribution (excluding Antarctica), but is concentrated in Australasia, Melanesia, and southern South America. Most species grow exclusively on trees, but some grow on rocks, moss, and/or soil. [1]
Menegazzia was described by the Veronese lichenologist Abramo Massalongo in 1854. [2] He named it after his friend Luigi Menegazzi (1795-1854), who was a naturalist. [3]
Placement of Menegazzia within the Parmeliaceae has now been confirmed by several molecular studies. [4] [5] [6] However, the exact position of the genus within the Parmeliaceae remains uncertain. It is unplaced within the Parmeliaceae. Previously, the morphologically similar genus Hypogymnia was thought to be the sister genus to Menegazzia, with some authors even separating these two genera into a family of their own, the Hypogymniaceae. [7] However, no molecular phylogenies to date have supported this grouping. [4] [5] [6]
There are three accepted subgenera within Menegazzia: Dispora, Octospora, and Megamenegazzia. [8] However, the monophyletic nature of these three groups remains unknown.
The thallus of Menegazzia is its most distinctive feature. It is foliose, dorsiventral, lobate, and often rosette-forming, though many species can also be irregularly spreading. It is heteromerous, that is, it contains an upper cortex, medulla, green algal layer (occupied by Trebouxia spp.), and lower cortex. The thallus can be loosely or closely attached to the substrate, depending on the species. Lobes are generally hollow and inflated, with perforations throughout the corticate upper surface. Only two species of Menegazzia are known which do not contain perforations ( M. eperforata , and an as yet undescribed taxon from Papua New Guinea). Many species can be sorediate, but only a few isidiate. Maculae are often present, especially at the lobe tips. The lower surface is also corticate, naked, and often uniformly attached to the substrate (except in M. inflata ). This surface is always blackened, and without rhizines. Internal cavities have walls which are most often white, but in some species they can be pigmented or blackened. [9]
Rounded apothecia are produced along the lamina of most of the known Menegazzia species, while the others are thought to be entirely asexual (like M. nothofagi and M. globulifera ). In the taxa that do produce apothecia, they are always lecanorine, and often cupuliform. They can be sessile, but more frequently are subpedicellate to pedicellate. The apothecial disc is concave to plane, matt to shining, or even pruinose in some taxa (like with M. dielsii ), with a well-developed thalline exciple. Epithecium is pigmented, and occasionally has granular inclusions. The hymenium is always colourless. Hypothecium is chondroid, and made-up of thick-walled, conglutinated cells. Paraphyses are netted, with apical cells that are sometimes capitate, and often pigmented to some extent. Asci are 2 or 8-spored. [9]
The ascospores are simple, colourless, ellipsoid, thick walled, with a broad range of dimensions: 20-120 × 10-50 µm. Pycnidia, if present, are produced along the lamina, and minute, immersed, and punctiform with a dark apex. Conidia, if present, are short and bacilliform. [9]
Members of the genus have a diverse chemistry, including fatty acids, depsides, depsidones, and pigments. [9]
Menegazzia species are most often corticolous, but several species are saxicolous, muscicolous, and/or terricolous. This group tends to be most abundant and diverse in Australasia and South America, commonly found in forests where southern beech ( Nothofagus ) dominates. They favour higher-elevation, moist, cool habitats. [10] Most species appear to be very slow growing, especially in dryer habitats, but more study is needed here.
Ascus evolution in Menegazzia is of particular interest, because many species have 2-spores per ascus, while nearly all other genera in the Parmeliaceae have 8-spores (making the character likely plesiomorphic for the family).
Menegazzia does not produce any economically important products, nor is it known to have had any uses by indigenous peoples. However, the genus is important for some small insects, which use the hollow lobes for shelter and the upper cortex for food.
Parmelia is a genus of medium to large foliose (leafy) lichens. It has a global distribution, extending from the Arctic to the Antarctic continent but concentrated in temperate regions. There are about 40 species in Parmelia. In recent decades, the once large genus Parmelia has been divided into a number of smaller genera according to thallus morphology and phylogenetic relatedness.
The Parmeliaceae is a large and diverse family of Lecanoromycetes. With over 2700 species in 71 genera, it is the largest family of lichen-forming fungi. The most speciose genera in the family are the well-known groups: Xanthoparmelia, Usnea, Parmotrema, and Hypotrachyna.
Collema is a genus of lichens in the family Collemataceae. The photobiont is the cyanobacterium genus Nostoc. Species in this genus typically grow on nutrient-rich bark or somewhat siliceous or calcareous rocks in humid environments.
Lecanora is a genus of lichen commonly called rim lichens. Lichens in the genus Squamarina are also called rim lichens. Members of the genus have roughly circular fruiting discs (apothecia) with rims that have photosynthetic tissue similar to that of the nonfruiting part of the lichen body (thallus). Other lichens with apothecia having margins made of thallus-like tissue are called lecanorine.
Buellia is a genus of mostly lichen-forming fungi in the family Caliciaceae. The fungi are usually part of a crustose lichen. In this case, the lichen species is given the same name as the fungus. But members may also grow as parasites on lichens (lichenicolous). The algae in the lichen is always a member of the genus Trebouxia.
Hypogymnia is a genus of foliose lichens in the family Parmeliaceae. They are commonly known as tube lichens, bone lichens, or pillow lichens. Most species lack rhizines that are otherwise common in members of the Parmeliaceae, and have swollen lobes that are usually hollow. Other common characteristics are relatively small spores and the presence of physodic acid and related lichen products. The lichens usually grow on the bark and wood of coniferous trees.
Vulpicida is a genus of lichenized fungi in the family Parmeliaceae. Circumscribed in 1993 to contain species formerly placed in Cetraria, the genus is widespread in Arctic to northern temperate regions, and contains six species. The genus is characterized by the presence of the secondary metabolites pulvinic acid and vulpinic acid, compounds that when combined with usnic acid, give the species their characteristic yellow and green colors.
Parmotrema is a genus of lichen belonging to the family Parmeliaceae. It is a large genus, containing an estimated 300 species, with a centre of diversity in subtropical regions of South America and the Pacific Islands.
Menegazzia terebrata is a species of foliose lichen found scattered across many continents, including North America, South America, Europe, Africa, and Asia.
Anzia is a genus of foliose lichens known as black-foam lichens in the large family Parmeliaceae. It was formerly included in the monogeneric family Anziaceae, but this has since been subsumed into the Parmeliaceae.
Phacopsis is a genus of lichenicolous (lichen-dwelling) fungi. They are parasites of members of the large lichen family Parmeliaceae, of which they are also a member. Originally proposed by Edmond Tulasne in 1852 to contain 3 species, Phacopsis now contains 10 species, although historically, 33 taxa have been described in the genus. Many of the species are poorly known, some of them having been documented only from the type specimen.
Lichens are symbiotic organisms made up of multiple species: a fungus, one or more photobionts and sometimes a yeast. They are regularly grouped by their external appearance – a characteristic known as their growth form. This form, which is based on the appearance of vegetative part of the lichen, varies depending on the species and the environmental conditions it faces. Those who study lichens (lichenologists) have described a dozen of these forms: areolate, byssoid, calicioid, cladoniform, crustose, filamentous, foliose, fruticose, gelatinous, leprose, placoidioid and squamulose. Traditionally, crustose (flat), foliose (leafy) and fruticose (shrubby) are considered to be the three main forms. In addition to these more formalised, traditional growth types, there are a handful of informal types named for their resemblance to the lichens of specific genera. These include alectorioid, catapyrenioid, cetrarioid, hypogymnioid, parmelioid and usneoid.
Punctelia perreticulata is a widely distributed species of foliose lichen in the family Parmeliaceae. It occurs in Mediterranean Europe and Russia, North America, South America, Australia, and New Zealand, where it grows on rocks, bark, or wood. Its main distinguishing features are its thallus surface, marked with many shallow depressions, grooves, or pits, and sorediate pseudocyphellae. The lower side of the thallus is ivory to tan towards the centre and the major secondary metabolite in the medulla is lecanoric acid. A lookalike species with which it has been historically confused is Punctelia subrudecta; this lichen can be distinguished from Punctelia perreticulata by the texture of the thallus surface, or, more reliably, by the length of its conidia.
Lathagrium is a genus of lichen-forming fungi in the family Collemataceae. It has 10 species of gelatinous lichens. Species in this genus typically grow on calcareous rocks, often amidst mosses, but can also be found on siliceous or serpentine rocks, mortar, or soil.
Punctelia graminicola is a species of foliose (leafy) lichen in the family Parmeliaceae. It grows on rocks, and, less frequently, on bark in North America, South America, and East Africa. It has a blue-grey thallus measuring up to about 15 cm (6 in), covered with tiny pores called pseudocyphellae. Sometimes the lichen forms small lobes that project out from the surface. Fruiting bodies are uncommon in this species; if present, they resemble small cups with a brown internal disc measuring 3–10 mm (0.1–0.4 in) in diameter. A lookalike species, Punctelia hypoleucites, is not readily distinguishable from Punctelia graminicola by appearance or habitat alone; these species can only be reliably differentiated by examining the length of their conidia.
Hypogymnia nitida is a species of foliose lichen in the family Parmeliaceae. It has a glossy dark brown upper surface and a strongly wrinkled, convoluted lower surface. Found in China, it was described as a new species in 2014.
Placomaronea kaernefeltii is a rare species of saxicolous (rock-dwelling) lichen in the family Candelariaceae. Found in South America, it was formally described as a new species in 2009 by lichenologists Martin Westberg, Patrik Frödén, and Mats Wedin. The type specimen was collected by the second author from Arica (Chile), between Socoroma and Putre, at an altitude of 3,750 m (12,300 ft), where it was found growing along cracks and pits on a siliceous boulder in a dry mountain slope. The lichen is only known to occur at its type locality, although the authors suggest a wider distribution is likely. The species epithet honours Swedish lichenologist Ingvar Kärnefelt.
Menegazzia endocrocea is a species of foliose lichen in the family Parmeliaceae. It is found in Australia. The lichen forms irregular rosettes up to 10 cm wide with hollow, cylindrical lobes that branch dichotomously, featuring a pale grey to cream-grey upper surface with roundish holes and a wrinkled, black lower surface. It has scattered apothecia with a reddish-brown disc, two-spored asci, and abundant pycnidia, identified chemically by compounds like atranorin and stictic acid.
Byssoloma xanthonicum is a species of corticolous (bark-dwelling), crustose lichen in the family Pilocarpaceae. It is found in New Caledonia.