''Herpothallon'' is a genus of crustose lichens in the family

Arthoniaceae The Arthoniaceae are a family of lichenized, lichenicolous and saprobic fungi in the order Arthoniales. The Arthoniaceae is the largest family of Arthoniales, with around 800 species. Most species in Arthoniaceae belong in '' Arthonia'' which is ...

. It has about 50 species.

Taxonomy

The genus was

circumscribed In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius. Not every polyg ...

in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineum'' assigned as the type species. Tobler erroneously believed that the fungus was a member of the

Basidiomycota Basidiomycota () is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya (often referred to as the "higher fungi") within the kingdom Fungi. Members are known as basidiomycetes. More specifically, Basi ...

. After it was recognized as an ascolichen, it was referred to either ''

Chiodecton ''Chiodecton'' is a genus of lichens in the family Roccellaceae. The genus was circumscribed by lichenologist Erik Acharius in 1814, with '' Chiodecton sphaerale'' assigned as the type species. Species , Species Fungorum accepts 22 species in '' ...

'' (family Roccellaceae) or ''

Cryptothecia ''Cryptothecia'' is a genus of white to greenish crustose lichens that grow on bark, wood, or leaves. in tropical or subtropical areas worldwide. It has a conspicuous prothallus that develops around its periphery which can be bright red in some s ...

'' (family

). In 2009, ''Herpothallon'' was resurrected following a publication by

André Aptroot André Aptroot (Heemskerk, 1961) is a Dutch mycologist and lichenologist. In 1993 he did his PhD at the University of Utrecht under the supervision of Robbert Gradstein (nl). His dissertation was titled "Systematic studies on pyrenocarpous li ...

, Göran Thor,

Robert Lücking Robert Lücking (born 1964) is a German lichenologist. He is a leading expert on foliicolous lichens–lichens that live on leaves. Life and career Born in Ulm in 1964, Lücking earned both his master's (1990) and PhD degree (1994) at the Univer ...

, and John Elix, in which they recognized 29 species worldwide. The type species is now known as ''

Herpothallon rubrocinctum ''Herpothallon'' is a genus of crustose lichens in the family Arthoniaceae. It has about 50 species. Taxonomy The genus was circumscription (taxonomy), circumscribed in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineu ...

'', or in the vernacular as the "Christmas lichen".

Description

''Herpothallon'' is characterized by the

byssoid Lichens are composite organisms made up of multiple species: a fungal partner, one or more photosynthetic partners, and sometimes a basidiomycete yeast. They are regularly grouped by their external appearance – a characteristic known as their g ...

(a wispy or cottony texture) prothallus (i.e., the first purely fungal layer upon which an algae-containing thallus develops) and hypothallus (i.e., a growth of undifferentiated purely fungal mycelium present as a distinct layer on the underside of the thallus). The texture of the thallus is somewhat felt-like, and its form is heteromerous, meaning that more or less distinct tissues are present, in particular, the

mycobiont A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.photobiont components occur in well-marked layers, with the photobiont in a more or less distinct zone between the upper cortex and the medulla. Another thallus feature common to all species is the felty pseudoisidia; these are isidia-like outgrowths that, unlike true isidia, lack internal differentiation and have no distinct cortex. The thallus also has pustules (blister-like elevations), and granules ranging in form and size from soredia-like to minute. The photobiont partner of the ''Herpothallon'' lichen is from '' Trentepohlia'', a genus of

green alga 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) have emerged deep in the Charophyte alga as ...

e. In ''Herpothallon'', the

asci ASCI or Asci may refer to: * Advertising Standards Council of India * Asci, the plural of ascus, in fungal anatomy * Accelerated Strategic Computing Initiative * American Society for Clinical Investigation * Argus Sour Crude Index * Association of ...

do not develop in true ascomata. Only two members of the genus, '' H. fertile'' and '' H. inopinatum'', are known to be fertile.

Species

, Species Fungorum accepts 49 species of ''Herpothallon''. *'' Herpothallon adnatum'' *''

Herpothallon alae ''Herpothallon'' is a genus of crustose lichens in the family Arthoniaceae. It has about 50 species. Taxonomy The genus was circumscribed in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineum'' assigned as the type ...

'' – Vanuatu *'' Herpothallon aurantiacoflavum'' *'' Herpothallon australasicum'' *'' Herpothallon biacidum'' – Australia *'' Herpothallon brialmonticum'' *''

Herpothallon capilliferum ''Herpothallon capilliferum'' is a species of corticolous (bark-dwelling), crustose lichen in the family Arthoniaceae. Found in China, it was formally described as a new species in 2022 by Pengfei Chen and Lulu Zhang. The type was collected fr ...

'' – China *'' Herpothallon cinereum'' *'' Herpothallon confluenticum'' *'' Herpothallon confusum'' *''

Herpothallon corallinum ''Herpothallon corallinum'' is a little-known species of corticolous lichen, corticolous (bark-dwelling), crustose lichen in the family Arthoniaceae. Found in the Democratic Republic of the Congo, it was species description, formally described a ...

'' *''

Herpothallon coralloides ''Herpothallon'' is a genus of crustose lichens in the family Arthoniaceae. It has about 50 species. Taxonomy The genus was circumscribed in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineum'' assigned as the type ...

'' –

Andaman Islands The Andaman Islands () are an archipelago in the northeastern Indian Ocean about southwest off the coasts of Myanmar's Ayeyarwady Region. Together with the Nicobar Islands to their south, the Andamans serve as a maritime boundary between th ...

*'' Herpothallon echinatum'' *''

Herpothallon elegans ''Herpothallon elegans'' is a rare species of corticolous (bark-dwelling), crustose lichen in the family Arthoniaceae. Found in Peru, it was formally described as new to science in 2009 by the lichenologist Göran Thor. It contains confluenti ...

'' *''

Herpothallon fertile ''Herpothallon fertile'' is a species of corticolous (bark-dwelling), crustose lichen in the family Arthoniaceae. Originally described from specimens collected in Costa Rica, it was formally described as new to science in 2009 by the lichenol ...

'' *''

Herpothallon flavominutum ''Herpothallon'' is a genus of crustose lichens in the family Arthoniaceae. It has about 50 species. Taxonomy The genus was circumscribed in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineum'' assigned as the type ...

'' – India *'' Herpothallon furfuraceum'' *'' Herpothallon glaucescens'' – China *''

Herpothallon globosum ''Herpothallon globosum'' is a little-known species of corticolous (bark-dwelling), crustose lichen in the family Arthoniaceae. Found in São Tomé and Príncipe, it was formally described as new to science in 2009 by the lichenologist Göran ...

'' *'' Herpothallon globuliferum'' – Andaman Islands *'' Herpothallon granulare'' *'' Herpothallon granulosum'' – India *'' Herpothallon himalayanum'' – India *'' Herpothallon hypoprotocetraricum'' *''

Herpothallon hyposticticum ''Herpothallon'' is a genus of crustose lichens in the family Arthoniaceae. It has about 50 species. Taxonomy The genus was circumscribed in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineum'' assigned as the type ...

'' – Galápagos Islands *'' Herpothallon inopinatum'' – Mexico *''

Herpothallon isidiatum ''Herpothallon'' is a genus of crustose lichens in the family Arthoniaceae. It has about 50 species. Taxonomy The genus was circumscription (taxonomy), circumscribed in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineu ...

'' – India *''

Herpothallon japonicum ''Herpothallon'' is a genus of crustose lichens in the family Arthoniaceae. It has about 50 species. Taxonomy The genus was circumscribed in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineum'' assigned as the type ...

'' *'' Herpothallon kigeziense'' – Uganda *'' Herpothallon lilacinum'' – China *'' Herpothallon lutescens'' – Andaman Islands *'' Herpothallon minimum'' *'' Herpothallon minutum'' – Andaman Islands *'' Herpothallon nigroisidiatum'' *'' Herpothallon philippinum'' *'' Herpothallon polyisidiatum'' – China *'' Herpothallon psorpseudisidiatum'' – Brazil *'' Herpothallon purpureum'' – Brazil *'' Herpothallon pustulatum'' *''

Herpothallon queenslandicum ''Herpothallon'' is a genus of crustose lichens in the family Arthoniaceae. It has about 50 species. Taxonomy The genus was circumscribed in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineum'' assigned as the type ...

'' *'' Herpothallon roseocinctum'' *'' Herpothallon rubrocinctoides'' *''

'' *'' Herpothallon rubroechinatum'' *'' Herpothallon rubromaculatum'' *'' Herpothallon saxorum'' – Galápagos Islands *'' Herpothallon subglobosum'' – China *'' Herpothallon tomentosum'' – China *'' Herpothallon tricolor'' *'' Herpothallon viridi-isidiatum'' – China *'' Herpothallon weii'' – China

References

Cited literature

* {{Taxonbar, from=Q10522484 Lichen genera Arthoniomycetes genera Taxa described in 1937