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
lichenized fungi
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Ramalinaceae
The Ramalinaceae are a family of lichenized fungi in the order Lecanorales. The family name is synonymous with the name ''Bacidiaceae''. Species of this family have a widespread distribution.
Genera
*''Aciculopsora''
*''Adelolecia''
*'' Arthro ...
, is a yellow-green
fruticose
A fruticose lichen is a form of lichen fungi that is characterized by a coral-like shrubby or bushy growth structure. It is formed from a symbiotic relationship of a photobiont such as green algae or less commonly cyanobacteria and one, two or mor ...
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 ...
being divided into narrow worm-like (vermis) branches (lacinia);the latter part of the name (lacinia) generally applied in descriptions and taxonomic keys such as exemplified in a key to
Sonoran Desert
The Sonoran Desert ( es, Desierto de Sonora) is a desert in North America and ecoregion that covers the northwestern Mexican states of Sonora, Baja California, and Baja California Sur, as well as part of the southwestern United States (in Arizona ...
species of ''
Ramalina
''Ramalina'' is a genus of greenish fruticose lichens that grow in the form of flattened, strap-like branches. Members of the genus are commonly called strap lichensField Guide to California Lichens, Stephen Sharnoff, Yale University Press, 201 ...
''.
The species of ''Vermilacinia'' are classified in two subgenera: subgenus ''Cylindricaria'' and subgenus ''Vermilacinia''. Subgenus ''Cylindricaria'', which includes 10+ species (type: ''Vermilacinia corrugata'' Spjut) that grow mostly on shrubs, is distinguished by a thin membranous pliable cortex (an outer skin-like layer composed of gelatinized hyphal cells) that expands as the thallus imbibes moisture, usually from fog, and shrinks upon drying (as fog dissipates). Subgenus ''Vermilacinia'', which includes 20 species (type: same as for the genus: ''Vermilacinia combeoides'' (Nyl.) Spjut & Hale) that grow on rocks (
saxicolous
A saxicolous lichen is a lichen that grows on rock. The prefix "sax" from the Latin means "rock" or "stone".
Characteristics
Saxicolous lichens exhibit very slow growth rates. They may develop on rock substrates for long periods of time, give ...
) and soil (
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 ...
), is distinguished by a relatively thick crusty cortex (like a dry pie crust) overlying a
medulla
Medulla or Medullary may refer to:
Science
* Medulla oblongata, a part of the brain stem
* Renal medulla, a part of the kidney
* Adrenal medulla, a part of the adrenal gland
* Medulla of ovary, a stroma in the center of the ovary
* Medulla of th ...
with rigid lattice of
hypha
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 ...
e.Spjut, R. W. 1995. ''Vermilacinia'' (Ramalinaceae, Lecanorales), a new genus of lichens. In: Flechten Follmann; Contr. Lichen in honor of Gerhard Follmann; F. J. A. Daniels, M. Schulz & J. Peine, eds., Koeltz Scientific Books: Koenigstein, pp. 337–351. The firmer cortex of subgenus ''Vermilacinia'' undoubtedly adds support to the thallus that allows its branches to grow upright from the substrate.
'' Niebla'' and ''Ramalina'' are related genera distinguished by the hyphae forming multiple longitudinal gelatinized cords (chondroid stands), within the medulla. In many species of ''Ramalina'' they form a network interconnected with the lower cortex and medulla, in contrast to a uniform lattice or a single central cord in the ''Vermilacinia'' medulla. Also, both ''Niebla'' and ''Vermilacinia'' have been included in ''Ramalina'', which is distinguished by the pale
pycnidia
A pycnidium (plural pycnidia) is an asexual fruiting body produced by mitosporic fungi, for instance in the order Sphaeropsidales ( Deuteromycota, Coelomycetes) or order Pleosporales (Ascomycota, Dothideomycetes). It is often spherical or inve ...
diterpene
Diterpenes are a class of chemical compounds composed of four isoprene units, often with the molecular formula C20H32. They are biosynthesized by plants, animals and fungi via the HMG-CoA reductase pathway, with geranylgeranyl pyrophosphate being ...
(−)-16 α-hydroxykaurane, and by the absence of the triterpene zeorin, in most species.
''Vermilacinia'' is also unique in the Ramalinaceae for producing the diterpene (−)-16 α-hydroxykaurane (common in nonlichen fungi)Enzien, M. and L. Margulis. 1988. ''Niebla ceruchis'' from Laguna Figueroa: dimorphic spore morphology and secondary compounds localized in pycnidia and apothecia. Microbios 55:75–83. among other lichen substances, notably zeorin and bourgeanic acid; depsidones are frequently present as accessory substances. The diterpene is found in all species of subgenus ''Vermilacinia'' and in most species of subgenus ''Cylindricaria''. Exceptions are two North American species
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...
to
Baja California
Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...
that only contain zeorin, or appearing deficient in lichen substances, although
usnic acid
Usnic acid is a naturally occurring dibenzofuran derivative found in several lichen species with the formula C18H16O7. It was first isolated by German scientist W. Knop in 1844 and first synthesized between 1933-1937 by Curd and Robertson. Usnic a ...
may be present in the cortex (''V. corrugata'', ''V. howei'').
This diterpene, known also as ceruchdiol, G., J. Santesson & C. W. Wachtmeister. 1965. Studies on the chemistry of lichens. 20. The chemistry of the ''Ramalina ceruchis'' group. Acta Chem. Scand. 19:1185–1187. or ceruchinol,, Follmann, G. 1966. Eine neue ''Ramalina''-Art uas der Ceruches-Gruppe. Willdenowia 4: 225–233. has been attributed to cause a
mildew
Mildew is a form of fungus. It is distinguished from its closely related counterpart, mould, largely by its colour: moulds appear in shades of black, blue, red, and green, whereas mildew is white. It appears as a thin, superficial growth consi ...
-like appearance that develops gradually on
herbarium
A herbarium (plural: herbaria) is a collection of preserved plant specimens and associated data used for scientific study.
The specimens may be whole plants or plant parts; these will usually be in dried form mounted on a sheet of paper (called ...
specimens. The thallus structure in some specimens collected more than 100 years ago is not discernible, making it difficult to determine whether or not
soredia
Soredia are common reproductive structures of lichens. Lichens reproduce asexually by employing simple fragmentation and production of soredia and isidia. Soredia are powdery propagules composed of fungal hyphae wrapped around cyanobacteria or gr ...
are present, which is necessary for species identification. The mold-like appearance is the result of
efflorescence
In chemistry, efflorescence (which means "to flower out" in French) is the migration of a salt to the surface of a porous material, where it forms a coating. The essential process involves the dissolving of an internally held salt in water, or ...
—a chemical change associated with the breakdown of the cortex from which the internal (medulla) hyphae erupt. Efflorescence can be slowed or prevented by storing specimens in a frost-free refrigerator below 40 °F, although there may be a trade-off in that long-term storage causes the cortex to become brittle over time (nine yrs).
Not all species of ''Vermilacinia'' that produce the diterpene exhibit efflorescence. The presence or absence of this condition has also been referred to in the literature as "deposit" and "no deposit". For example, Gerd Bendz, Johan Santesson and Carl Wachtmeister reported on two specimens of ''Ramalina homalea'' (=''Niebla homalea'') with the diterpene that were collected in 1874, one with "deposit", the other without "deposit"; however, it was not clear as to how their specimens were identified to species. In this case the taxonomy was probably based on R. Heber Howe. The presence of divaricatic acid noted in the one specimen to have the deposit included reference to Mason E Hale Jr., ''Lichen Handbook''. Although one of the two specimens was probably ''Vermilacinia laevigata'', the
chemotype A chemotype (sometimes chemovar) is a chemically distinct entity in a plant or microorganism, with differences in the composition of the secondary metabolites. Minor genetic and epigenetic changes with little or no effect on morphology or anatomy m ...
s appear incorrectly reported as generally recognized for the species now known as ''Niebla homalea'', which does not produce the diterpene. The same chemical data for ''Ramalina homalea'' were also reported by Gerhard Follmann, which again appear to include misidentifications for other lichen substances, without accounting for type specimens. Additionally, no reference was made to zeorin being present; the reported presence of
stictic acid
Stictic acid is an aromatic organic compound, a product of secondary metabolism in some species of lichens.
Stictic acid is the subject of preliminary biomedical research. Stictic acid has cytotoxic and apoptotic effects ''in vitro''. Computation ...
was likely a misidentification for
salazinic acid
Salazinic acid is a depsidone with a lactone ring. It is found in some lichens, and is especially prevalent in ''Parmotrema'' and ''Bulbothrix'', where its presence or absence is often used to help classify species in those genera.
History
I ...
and that of
atranorin
Atranorin is a chemical substance produced by some species of lichen. It is a secondary metabolite belonging to a group of compounds known as depsides. Atranorin has analgesic, anti-inflammatory, antibacterial, antifungal, cytotoxic, antioxidant, ...
a misidentification of
usnic acid
Usnic acid is a naturally occurring dibenzofuran derivative found in several lichen species with the formula C18H16O7. It was first isolated by German scientist W. Knop in 1844 and first synthesized between 1933-1937 by Curd and Robertson. Usnic a ...
. The mold-like condition (“deposit”) has been associated with the occurrence of an unknown terpene ("T3"), which may be related to bourgeanic acid.
The "Ceruchis-Group", which was defined by Gerhard Follmann by the presence (−)-16 α-hydroxykaurane, included species subsequently classified by Peter Bowler in three groups within the genus ''Niebla'' (1) ''N. homalea'', (2) ''N. combeoides'', and (3) ''N. ceruchis''.Bowler, P.A. 1981. Cortical diversity in the Ramalinaceae. Can. J. Bot. 59: 437–453. The first two groups are generally recognized to grow on rocks, the third group (''N. ceruchis'') on trees and shrubs; however, the type for the species in the “''Niebla ceruchis'' group” is one that grows on sand and rock; the type compares closely to specimens that lack a holdfast, as might be expected for thalli growing on soil. A specimen collected by Charles Darwin was noted by him to have been found at "
Iquique
Iquique () is a port city and commune in northern Chile, capital of both the Iquique Province and Tarapacá Region. It lies on the Pacific coast, west of the Pampa del Tamarugal, which is part of the Atacama Desert. It has a population of 191,468 ...
, 2,000 to 3,000 ft high, where clouds often hang, lying without adhesion on bare sand ... through the coast mountains, no other plant on the coast for 16
league
League or The League may refer to:
Arts and entertainment
* ''Leagues'' (band), an American rock band
* ''The League'', an American sitcom broadcast on FX and FXX about fantasy football
Sports
* Sports league
* Rugby league, full contact footba ...
s inward" (Taylor Herbarium within the Farlow Herbarium, Harvard University. ''Vermilacinia ceruchis'' was described to have a cortex 75–125
microns
The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...
thick, to lack apothecia, and to contain three characteristic terpenes of the ''N. combeoides'' group, described by Peter Bowler to have a thick cortex up to 200+ microns, in contrast to the
corticolous lichen A corticolous lichen is a lichen that grows on bark.Alan Silverside's Lichen Glossary (a-f), Alan Silverside/ref> This is contrasted with lignicolous lichen, which grows on wood that has had the bark stripped from it,Alan Silverside's Lichen Glos ...
species, not more than 60 microns thick. There seems to be no disagreement on the morphological differences between the corticolous and saxicolous groups, only a lack of applying the appropriate types to the names, according to the
International Code of Botanical Nomenclature
The ''International Code of Nomenclature for algae, fungi, and plants'' (ICN) is the set of rules and recommendations dealing with the formal botanical names that are given to plants, fungi and a few other groups of organisms, all those "trad ...
. Despite the continued reports indicating that ''Niebla ceruchis'', which is a synonym of ''Vermilacinia ceruchis,'' to occur on shrubs and trees in North America, it does not occur in North America. ''Vermilacinia ceruchis'' is endemic to South America, and may be extinct.
The South America species of
subgenus
In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus.
In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...
''Cylindricaria'' often differ from the North American species by containing methyl 3,5-dichlorolecanorate, also known as tumidulin. This was made in reference to the compound having allegedly been discovered in ''Ramalina ceruchis'' var. ''tumidula'' (
basionym
In the scientific name of organisms, basionym or basyonym means the original name on which a new name is based; the author citation of the new name should include the authors of the basionym in parentheses. The term "basionym" is used in both botan ...
''Usnea tumidula'');Huneck, S. and G. Follmann. 1965. Zur Chemie chilenischer Flechtern XVI. Über die Inhaltasstoffe von ''Ramalina ceruchis'' (ACH.) DE NOT. var. ''tumidula'' (TAYL.) NYL Zeitschrift für Naturforschung 20b(6): 611–612. However, the type specimen does not contain this compound. The references to the material from which the compound was isolated include a figure showing thalli growing on a cactus, ''Eulychnia acida'', not on sand or rock. The report of lichen substances being present in species—without reference to type specimens—has led to considerable confusion. Many specimens of ''Vermilacinia'' in the United States National Herbarium (Smithsonian Institution, Department of Botany)—annotated by species names in the genus ''Niebla'' collected in North America—were erroneously reported to contain methyl 3,5-dichlorolecanorate, which may have been deduced from the previous erroneous reports mentioned above; the compound in question appears to be unknown, T3.
Vermilacinia paleoderma
''Vermilacinia paleoderma'' is a pale yellow-green fruticose lichen that occurs commonly along the fog zone of the Pacific Coast of Northern Vizcaíno Desert region of Baja Californica and occasionally in the Chaparral Islands of California.Spju ...
''
*''
Vermilacinia polymorpha
''Vermilacinia polymorpha'' is a fruticose lichen infrequently found on Santa Catalina Island (California), Santa Catalina Island in the Channel Islands of California and along the mainland coast in Ventura County, California, Ventura and Orange, ...
Vermilacinia robusta
''Vermilacinia robusta'' is an olive green fruticose lichen that occurs on rocks near ocean mist along the foggy Pacific Coast of southern California to northern Baja California and offshore islands.Spjut, R. W. 1996. ''Niebla'' and ''Vermilacini ...
Vermilacinia leonis
''Vermilacinia leonis'' is a fruticose lichen usually found on branches of shrubs in the fog regions along the Pacific Coast of North America and South America; in North America it is found on the southern half of the main peninsula of Baja Calif ...