''Ramalina menziesii'', the lace lichen or fishnet, is a pale yellowish-green to grayish-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 ...

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship. It becomes a deeper green when wet.

Apothecia An ascocarp, or ascoma (), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are mo ...

are lecanorine. Lace lichen is an important food source for

deer Deer or true deer are hoofed ruminant mammals forming the family Cervidae. The two main groups of deer are the Cervinae, including the muntjac, the elk (wapiti), the red deer, and the fallow deer; and the Capreolinae, including the reindeer ...

in the Coast Range of

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, and a source of nest material for birds. It is highly variable in its growth form, with branches sometimes so slender as to appear like strands, sometimes tiny, and sometimes large with broadly flattened branches. After years of effort, the California Lichen Society was able to convince the state legislature to recognize the lichen as the state lichen of

, the first lichen so honored.

Taxonomy

In 1775, the species was given its first Linnean binomial name of ''Lichen retiformis'' by

Archibald Menzies Archibald Menzies ( ; 15 March 1754 – 15 February 1842) was a Scottish surgeon, botanist and naturalist. He spent many years at sea, serving with the Royal Navy, private merchants, and the Vancouver Expedition. He was the first recorded Euro ...

. It was also referred to as ''Lichen reticulatis'' by Nohden in 1801. Thomas Taylor then incorporated the taxon into the genus ''Ramalina'' and described it in the London Journal of Botany in 1847 as ''Ramalina menziesii''.

Vernacular name A vernacular or vernacular language is in contrast with a "standard language". It refers to the language or dialect that is spoken by people that are inhabiting a particular country or region. The vernacular is typically the native language, n ...

s used for the species include "lace lichen" and "fishnet".

Description

''Ramalina menziesii'' is a

epiphytic An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.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 ...

. Expansion of its perforated tissue from the thallus apex produces its net-like morphology. This

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

ranges from thick nets in sunny regions to thin filaments in foggy regions. Studies have suggested that this morphological variation is a result of both genetic differences between populations, as well as

phenotypic plasticity Phenotypic plasticity refers to some of the changes in an organism's behavior, morphology and physiology in response to a unique environment. Fundamental to the way in which organisms cope with environmental variation, phenotypic plasticity encompa ...

within the species.

Lichen spot test A spot test in lichenology is a spot analysis used to help identify lichens. It is performed by placing a drop of a chemical on different parts of the lichen and noting the colour change (or lack thereof) associated with application of the chemical ...

s on the

cortex Cortex or cortical may refer to: Biology * Cortex (anatomy), the outermost layer of an organ ** Cerebral cortex, the outer layer of the vertebrate cerebrum, part of which is the ''forebrain'' *** Motor cortex, the regions of the cerebral cortex i ...

are K−, C−, P− and KC+ (dark yellow). Ramalina menziesii 106175427

Distribution and habitat

''Ramalina menziesii'' is found from the Baja California of Mexico to the temperate rainforests of Alaska, with six distinct

ecoregions An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of l ...

. Throughout their distribution, the occupied habitat differs in relation to the distance from the coast. In Baja California, lace lichen is most common on shrubs in the coastal fog deserts and on cacti, shrubs and trees in the inland chaparral habitats. In coastal California, lace lichen is found in habitats dominated by coastal live oak, tan oak,

California laurel ''Umbellularia californica'' is a large hardwood tree native to coastal forests and the Sierra foothills of California, and to coastal forests extending into Oregon. It is endemic to the California Floristic Province. It is the sole species in th ...

red alder ''Alnus rubra'', the red alder, is a deciduous broadleaf tree native to western North America (Alaska, Yukon, British Columbia, Washington, Oregon, California, Idaho and Montana). Description Red alder is the largest species of alder in North A ...

, and

willow Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist s ...

. In the Californian inland, the habitats are dominated by

oak savannas An oak savanna is a type of savanna—or lightly forested grassland—where oaks (''Quercus ''spp.) are the dominant trees. The terms "oakery" or "woodlands" are also used commonly, though the former is more prevalent when referencing the Mediter ...

of valley oak, blue oak, and coastal live oak. The northern and southern Californian habitats are geographically separated from the coastal range. As you move towards the Pacific Northwest, lace lichen is found in temperate mixed coniferous forests of

Sitka spruce ''Picea sitchensis'', the Sitka spruce, is a large, coniferous, evergreen tree growing to almost tall, with a trunk diameter at breast height that can exceed 5 m (16 ft). It is by far the largest species of spruce and the fifth-larg ...

western hemlock ''Tsuga heterophylla'', the western hemlock or western hemlock-spruce, is a species of hemlock native to the west coast of North America, with its northwestern limit on the Kenai Peninsula, Alaska, and its southeastern limit in northern Sonoma ...

, and some broad-leafed species. Moving inland in their northern distribution, lace lichen quickly disappear. The range of the lichen continues north along the Pacific Coast of

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

, extending to

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...

. In the deciduous

blue oak ''Quercus douglasii'', known as blue oak, is a species of oak endemic to (and found only in) California, common in the Coast Ranges and the foothills of the Sierra Nevada. It is California's most drought-tolerant deciduous oak, and is a dominan ...

(''Quercus douglasii'') woodlands of central coastal California, ''Ramalina menziesii'' has an important role in the annual turnover of

biomass Biomass is plant-based material used as a fuel for heat or electricity production. It can be in the form of wood, wood residues, energy crops, agricultural residues, and waste from industry, farms, and households. Some people use the terms bi ...

. The standing biomass of this and other epiphytic lichens was determined to be 515 grams per tree, equivalent to 706 kilograms per

hectare The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100-metre sides (1 hm2), or 10,000 m2, and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. An acre is a ...

; of this, 94% is ''R. menziesii''. Despite this area being much drier than those in other similar studies, ''R. menziesii'' was shown to contribute as much to biomass and nutrient turnover as other epiphytic lichens from wetter locales. A study on ''Ramalina menziesii'' across its range from Baja California del Norte to the Queen Charlotte Islands revealed patterns of morphological variation influenced by environmental factors. Key findings include a correlation between the number of perforations in the lichen's net buds and both proximity to the coast and latitude, with coastal samples having fewer perforations and a decrease in perforations with increasing latitude, particularly noticeable north of central Oregon where samples are exclusively coastal. Additionally, the study found significant relationships between morphological variations and environmental factors such as NaCl concentration and annual temperature variation, although the distribution of different forms of ''R. menziesii'' and patterns of annual precipitation showed some alignment, the presence and form of ''R. menziesii'' did not correlate with the distribution of eight tree species that serve as its substrate.

Photobiont

Lichen are a great example of a symbiotic interaction between a fungal body and an algal photobiont. The

photobiont A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.photosynthesis Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored i ...

, while the fungal body provides a habitat. 94% of the photobiont lineages of ''Ramalina menziesii'' are associated with ''

Trebouxia decolorans ''Trebouxia'' is a unicellular green alga.Silverside, A. J. (2009). Retrieved from http://www.bioref.lastdragon.org/Chlorophyta/''Trebouxia''.html It is a photosynthetic organism that can exist in almost all habitats found in polar, tropical, and ...

,'' while the remainder are '' Trebouxia jamesii''. While ''Ramalina menziesii'' only associates with one algal species, it has been found in association with six other fungal species. ''Trebouxia decolorans'' shows significant genetic structure depending on the ecoregion, phorophyte species, and climate. This structure was likely shaped by geographic barriers or differences in climate and habitat. Within each ecoregion, specialization of ''T. decolorans'' to its specific

phorophyte In botany phorophytes are plants, on which epiphyte An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. Th ...

species was found. This allows for

local adaptation Local adaptation is a mechanism in evolutionary biology whereby a population of organisms evolves to be more well-suited to its local environment than other members of the same species that live elsewhere. Local adaptation requires that different po ...

and has an impact on the genetic structure of the population.

Bioindicators

Lichen have long been used as

bioindicators A bioindicator is any species (an indicator species) or group of species whose function, population, or status can reveal the qualitative status of the environment. The most common indicator species are animals. For example, copepods and other sma ...

for

atmospheric pollution Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different types ...

because they derive much of their resources from the air. Many species are also sensitive to environmental change, making them accurate warning signs for pollution. A study of archived ''Ramalina menziesii'' specimens showed a history of lead contamination in California. Lead concentrations in lace lichen peaked in 1976 at 880 μg/g due to

leaded gasoline Tetraethyllead (commonly styled tetraethyl lead), abbreviated TEL, is an organolead compound with the formula Pb( C2H5)4. It is a fuel additive, first being mixed with gasoline beginning in the 1920s as a patented octane rating booster that all ...

emissions and have since decreased to 0.2–4.7 μg/g. In recent years, ''Ramalina menziesii'' has bioaccumulated of

monomethylmercury Methylmercury (sometimes methyl mercury) is an organometallic cation with the formula . It is the simplest organomercury compound. Methylmercury is extremely toxic, and its derivatives are the major source of organic mercury for humans. It is a ...

(MMHg) from coastal marine atmospheric fog. High concentrations found in lace lichen are transmitted to the deer that consume them, and later to the

apex predator An apex predator, also known as a top predator, is a predator at the top of a food chain, without natural predators of its own. Apex predators are usually defined in terms of trophic dynamics, meaning that they occupy the highest trophic lev ...

s that consume the deer—a process called

biomagnification Biomagnification, also known as bioamplification or biological magnification, is any concentration of a toxin, such as pesticides, in the tissues of tolerant organisms at successively higher levels in a food chain. This increase can occur as a ...

. Although fog-borne MMHg only accounts for a small percentage of atmospheric deposition, it may have a disproportionate impact leading to toxicological effects on ''

Puma concolor The cougar (''Puma concolor'') is a large cat native to the Americas. Its range spans from the Canadian Yukon to the southern Andes in South America and is the most widespread of any large wild terrestrial mammal in the Western Hemisphere. ...

'' in coastal California.

Historical uses

''Ramalina menziesii'' was first documented for its use by indigenous tribes of California. The

Kawaiisu people The Kawaiisu (pronounced: ″ka-wai-ah-soo″) are a Native Californian ethnic group in the United States who live in the Tehachapi Valley and to the north across the Tehachapi Pass in the southern Sierra Nevada, toward Lake Isabella and Walk ...

reportedly used it for its magical properties. It would be placed in water to bring rain or placed in fire to repel thunder or lightning. The Kashaya Pomo people in Northern California used it as a sanitary material.