''Peltigera'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of approximately 100 species of foliose

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Peltigeraceae. Commonly known as the dog or pelt lichens, species of ''Peltigera'' are often

terricolous A terricolous lichen is a lichen that grows on the soil as a substrate. An example is some members of the genus ''Peltigera ''Peltigera'' is a genus of approximately 100 species of foliose lichens in the family Peltigeraceae. Commonly known as ...

(growing on soil), but can also occur on moss, trees, rocks, and many other substrates in many parts of the world. Most species of ''Peltigera'' have the cyanobacterium ''

Nostoc ''Nostoc'', also known as star jelly, troll’s butter, spit of moon, fallen star, witch's butter (not to be confused with the fungi commonly known as witches' butter), and witch’s jelly, is the most common genus of cyanobacteria found in vari ...

'' as the dominant

photobiont A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Coccomyxa ''Coccomyxa'' is a genus of green algae The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) h ...

.'' The presence of both a green alga and a cyanobacterium makes some tripartite; in this case they show cephalodium growths containing the third partner, ''Nostoc''. Because of their ability to fix nitrogen from the atmosphere, such lichens are influential in

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

composition and generation.

Description

Species of ''Peltigera'' are foliose, with broad lobed

thalli Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms were ...

. Although the size of the thalli is variable and species-dependent, in some species the thalli can grow quite large, up to 30 cm in diameter.Vitikainen O. (1994). (1998). Taxonomic notes on neotropical species of ''Pelitgera''. In: Lichenology in Latin America: history, current knowledge and applications. Edited by M. P. Marcelli, and M.R.D. Seaward. CETESB, Companhia de Tecnologia de Saneamento Ambiental, Estado de Sao Paulo. pp. 135-139. The color of the upper surface may range from drab gray, brown or greenish. Lower surfaces are typically ''without'' a cortex (unlike other

foliose lichen Foliose lichen is one of the morphological classes of lichens, which are complex organisms that arise from the symbiotic relationship between fungi and a photosynthetic partner, typically algae. This partnership allows lichen to live in diverse ...

s),Fioliose lichens, Lichen Thallus Types, Allan Silverside
/ref> and cottony, often with fungal

hyphae A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or ...

fused to form a network of veins. The reproductive structures

isidia An isidium is a vegetative reproductive structure present in some lichens. Isidia are outgrowths of the thallus surface, and are corticated (i.e., containing the outermost layer of the thallus), usually with a columnar structure, and consisting o ...

, soredia or lobules may be present in some species. All species of ''Peltigera'' associate with the nitrogen-fixing cyanobacteria ''

''. ''Peltigera'' can be distinguished from the equally large and leaf-like lichen, ''

Nephroma ''Nephroma'' is a genus of medium to large foliose lichens. The genus has a widespread distribution. They are sometimes called kidney lichens, named after the characteristic kidney-shaped apothecia that they produce on the lower surface of their ...

'', by its veined lower cortex; ''Nephroma'', by contrast, has a smooth, unveiled lower cortex.

Habitat

''Peltigera'' are mainly ground-dwelling, but can also be found on mosses or dead wood. Some species are used as forest succession indicators.

Taxonomy

In 1753, Linnaeus first described the species ''Lichen apthosus'' and ''L. caninus'' back when all known lichens were grouped into the genus ''Lichen''. Later, in 1787,

Willdenow Carl Ludwig Willdenow (22 August 1765 – 10 July 1812) was a German botanist, pharmacist, and plant taxonomist. He is considered one of the founders of phytogeography, the study of the geographic distribution of plants. Willdenow was al ...

circumscribed the genus ''Peltigera'', and redescribed '' P. aphthosa'' and '' P. canina''. The generic name is derived from the

Latin language Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through ...

''pelta'' (small shield), and refers to the shield-shaped

thallus Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms wer ...

in these species. The common name, the dog lichen, refers to the perceived resemblance of ''P. caninus'' to a dog.

Phylogeny

In a comparative analysis of both morphological and chemical characteristics as well as sequences of large subunit nuclear

ribosomal DNA Ribosomal DNA (rDNA) is a DNA sequence that codes for ribosomal RNA. These sequences regulate transcription initiation and amplification, and contain both transcribed and non-transcribed spacer segments. In the human genome there are 5 chromos ...

, it was shown that the genus ''Peltigera'' is

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

. Several species, such as '' P. canina'', have been changed to a group as there appears to be several species clustered under a single name.

Distribution

The ''Peltigera'' have a widespread distribution, and are found on all continents. There are 34

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

n species, 30

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

an species, 25 species from

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

, and 16 species from

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

Species

Apfelflechte Peltigera aphtosa OhWeh-005

*'' Peltigera aphthosa'' *'' Peltigera aquatica'' *''

Peltigera britannica ''Peltigera britannica'' is a species of foliose lichen belonging to the family Peltigeraceae The Peltigeraceae are a family of lichens in the order Peltigerales. The Peltigeraceae, which contains 15 genera and about 600 species, has recently ...

'' *'' Peltigera canina'' *'' Peltigera castanea'' *'' Peltigera chionophila'' *''

Peltigera collina ''Peltigera'' is a genus of approximately 100 species of foliose lichens in the family Peltigeraceae. Commonly known as the dog or pelt lichens, species of ''Peltigera'' are often terricolous (growing on soil), but can also occur on moss, trees, ...

'' *''

Peltigera degenii ''Peltigera degenii'' is a species of foliose lichen in the family Peltigeraceae. It was first formally described in 1927 by Hungarian lichenologist Vilmos Kőfaragó-Gyelnik Vilmos Kőfaragó-Gyelnik (March 30, 1906 – March 15, 1945) was a H ...

'' *'' Peltigera didactyla'' *'' Peltigera dilacerata'' *''

Peltigera dolichorhiza ''Peltigera'' is a genus of approximately 100 species of foliose lichen, foliose lichens in the family (biology), family Peltigeraceae. Commonly known as the dog or pelt lichens, species of ''Peltigera'' are often terricolous lichen, terricolous ...

'' *'' Peltigera elisabethae'' *''

Peltigera extenuata ''Peltigera'' is a genus of approximately 100 species of foliose lichen, foliose lichens in the family (biology), family Peltigeraceae. Commonly known as the dog or pelt lichens, species of ''Peltigera'' are often terricolous lichen, terricolous ...

'' *'' Peltigera fimbriata'' *'' Peltigera gowardii'' *'' Peltigera granulosa'' *''

Peltigera horizontalis ''Peltigera horizontalis'' is a species of lichen in the family Peltigeraceae. It was first species description, described by British botanist William Hudson (botanist), William Hudson in 1762 as ''Lichen horizontalis''. German botanist Johann Ch ...

'' *''

Peltigera hydrophila ''Peltigera hydrophila'' is a species of foliose lichen in the family Peltigeraceae. First species description, described in 2020, it distinguishes itself through a distinct, hairless thallus that turns deep blue-violet when it becomes wet. Foun ...

'' *'' Peltigera hydrothyria'' *''

Peltigera hymenina ''Peltigera'' is a genus of approximately 100 species of foliose lichens in the family Peltigeraceae. Commonly known as the dog or pelt lichens, species of ''Peltigera'' are often terricolous (growing on soil), but can also occur on moss, trees ...

'' *'' Peltigera isidiophora'' *'' Peltigera islandica'' *'' Peltigera koponenii'' *'' Peltigera lactucifolia'' *'' Peltigera lairdii'' *'' Peltigera latiloba'' *'' Peltigera lepidophora'' *'' Peltigera leptoderma'' *''

Peltigera leucophlebia ''Peltigera leucophlebia'' is a lichenized fungus in the family Peltigeraceae. It is commonly called ruffled freckled pelt. This and other species in the genus contain a green algae in the genus '' Coccomyxa'' and also cyanobacteria in the genu ...

'' *'' Peltigera malacea'' *'' Peltigera membranacea'' *'' Peltigera montis-wilhelmii'' *''

Peltigera neckeri ''Peltigera neckeri'' is a foliose lichen in the family Peltigeraceae. It is commonly called black saddle pelt. It is distinguished by its unique tubular apothecia, which resemble black saddles or painted finger nails. Ecology ''Peltigera necker ...

'' *''

Peltigera neodegenii ''Peltigera'' is a genus of approximately 100 species of foliose lichens in the family Peltigeraceae. Commonly known as the dog or pelt lichens, species of ''Peltigera'' are often terricolous (growing on soil), but can also occur on moss, trees, ...

'' *'' Peltigera neorufescens '' *''

Peltigera papuana ''Peltigera papuana'' is a lichen-forming fungus in the family Peltigeraceae. It was species description, described in 2009 from Madang Province of Papua New Guinea, which inspired its botanical name, specific epithet. Genetic analysis of both t ...

'' *'' Peltigera polydactylon'' *'' Peltigera ponojensis'' *'' Peltigera praetextata'' *'' Peltigera pulverulenta'' *'' Peltigera pusilla'' *'' Peltigera rufescens'' *'' Peltigera scabrosa'' *'' Peltigera scabrosella'' *'' Peltigera seneca'' *'' Peltigera serusiauxii'' *'' Peltigera shennongjiana'' – China *''

Peltigera sorediifera ''Peltigera'' is a genus of approximately 100 species of foliose lichens in the family Peltigeraceae. Commonly known as the dog or pelt lichens, species of ''Peltigera'' are often terricolous (growing on soil), but can also occur on moss, trees ...

'' *''

Peltigera subhorizontalis ''Peltigera'' is a genus of approximately 100 species of foliose lichen, foliose lichens in the family (biology), family Peltigeraceae. Commonly known as the dog or pelt lichens, species of ''Peltigera'' are often terricolous lichen, terricolous ...

'' *'' Peltigera tartarea'' *''

Peltigera tereziana ''Peltigera'' is a genus of approximately 100 species of foliose lichens in the family Peltigeraceae. Commonly known as the dog or pelt lichens, species of ''Peltigera'' are often terricolous (growing on soil), but can also occur on moss, trees ...

'' *''

Peltigera vainioi ''Peltigera vainioi'' is a species of lichen in the family Peltigeraceae. It is found in high-elevation locations in South America. It is a somewhat unusual species in its genus, characterized by a single holdfast that attaches to its substrate ...

'' *''

Peltigera venosa ''Peltigera venosa'', commonly known as the fan lichen, is a species of foliose lichen in the family Peltigeraceae. It was first species description, described by Carl Linnaeus in his 1753 work ''Species Plantarum'' as ''Lichen venosus''. German ...

'' *''

Peltigera weberi ''Peltigera weberi'' is a rare species of foliose lichen in the family Peltigeraceae. It is found in Papua New Guinea, where it grows on road banks and on earth and rock debris. Taxonomy The lichen was species description, formally described a ...

'' *'' Peltigera wulingensis''

Uses

''Peltigera'' species has been used historically to treat wounds, urinary disorders,

thrush ''The Man from U.N.C.L.E.'' is an American spy fiction television series produced by Metro-Goldwyn-Mayer Television and first broadcast on NBC. The series follows secret agents, played by Robert Vaughn and David McCallum, who work for a secret ...

tuberculosis Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in ...

, and

rabies Rabies is a viral disease that causes encephalitis in humans and other mammals. Early symptoms can include fever and tingling at the site of exposure. These symptoms are followed by one or more of the following symptoms: nausea, vomiting, vi ...

. '' P. apthosa'' was used as a remedy for cough and infantile

aphthae Aphthous stomatitis, or recurrent aphthous stomatitis (RAS), is a common condition characterized by the repeated formation of benign and non-contagious mouth ulcers (aphthae) in otherwise healthy individuals. The informal term ''canker sore'' ...

. ''P. furfuracea'' has shown potent antioxidant activity and reducing power. Similarly, ''Peltigera'' specimens from Hawaii and Iceland have also been reported to show pronounced antioxidant activity.

Food source

Although a few reports have described

caribou Reindeer (in North American English, known as caribou if wild and ''reindeer'' if domesticated) are deer in the genus ''Rangifer''. For the last few decades, reindeer were assigned to one species, ''Rangifer tarandus'', with about 10 subspe ...

and

reindeer Reindeer (in North American English, known as caribou if wild and ''reindeer'' if domesticated) are deer in the genus ''Rangifer''. For the last few decades, reindeer were assigned to one species, ''Rangifer tarandus'', with about 10 subspe ...

feeding on the

of ''Peltigera'', in general, species of ''Peltigera'' are not commonly used as a food source by mammals. A study of the grazing habits of the land snails ''

Cantareus aspersa ''Cornu aspersum'' (syn. ''Cryptomphalus aspersus''), known by the common name garden snail, is a species of land snail in the family Helicidae, which includes some of the most familiar land snails. Of all terrestrial molluscs, this species may w ...

'' and ''

Limax ''Limax'' is a genus of air-breathing land slugs in the terrestrial pulmonate gastropod mollusk family Limacidae. The generic name ''Limax'' literally means "slug". Some species, such as the leopard slug (''L. maximus'') and the tawny garden ...

'' species revealed that these snails prefer to eat ''Peltigera'' species (such as '' P. praetextata'') that are lacking in secondary metabolites.

Bioactive compounds

'' contains the compounds tenuiorin and methyl orsellinate, which are inhibitory to the enzyme 15-lipoxygenase. Tenuiorin is also known to occur in '' P. apthosa'', '' P. malacea'' and '' P. neckeri''. A mixture of methyl and ethyl orsellinates have been identified from ''P. aphthosa'' that had

antibacterial An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...

activity against Gram-positive and -negative bacteria. The novel non-protein

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...

s solorinine and peltigerine have been detected in various species of ''Peltigera''.

Description

Habitat

Taxonomy

Phylogeny

Distribution

Species

Uses

Food source

Bioactive compounds

References

Further reading