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  • fungi
  • There has been a long-standing interest in understanding geographical distributions of lichen-forming fungi and the factors that shape these distributions. (springer.com)
  • Given our limited ability to make generalizable inferences and predictions on species distributions within a historical biogeographic framework, we emphasize that a more effective incorporation of an ecological biogeographic perspective into biogeographic research of lichen-forming fungi will provide an improved understanding of the range of factors shaping distributions of species. (springer.com)
  • In this chapter, we briefly discuss general perspectives of biogeography of lichen-forming fungi, followed by a synthesis of four major themes directly related to ecological biogeography, including (1) dispersal and establishment of lichens, (2) landscape genetics and gene flow, (3) modeling lichen distributions, and (4) the role photobionts play in determining distributional ranges. (springer.com)
  • photobiont
  • Blaha J, Baloch E, Grube M (2006) High photobiont diversity associated with the euryoecious lichen-forming ascomycete Lecanora rupicola (Lecanoraceae, Ascomycota). (springer.com)
  • thalli
  • Lichens do not have a waxy cuticle like plants have on their leaves, nor do they have vascular tissue such as xylem and phloem to move nutrients and water around their thalli as a plant does. (fed.us)
  • In addition to their morphological forms, lichen thalli are also classified by the ratio of phycobiont cells (i.e., cells of the photosynthetic partner) to mycobiont cells (i.e., cells of the fungus). (britannica.com)
  • give the lichen
  • Green algae generally give the lichen a bright green color when wet, although there are exceptions of pigmented lichens with green algae due to the fungal partner showing its colors. (fed.us)
  • Cyanobacteria will give the lichen a dark green, brown, or black color. (fed.us)
  • Vulpinic acid is both toxic and bright yellow, and, besides making the lichen poisonous, it can also give the lichen a yellowish tint. (wikipedia.org)
  • algal
  • When a lichen is wet, those cells become transparent, and the algal cells underneath get a chance to show their vibrancy. (fed.us)
  • In a few remarkable cases, a single lichen fungus can develop into two very different lichen forms when associating with either a green algal or a cyanobacterial symbiont. (wikipedia.org)
  • In lichens that include both green algal and cyanobacterial symbionts, the cyanobacteria may be held on the upper or lower surface in small pustules called cephalodia. (wikipedia.org)
  • The most important difference that distinguishes fruticose lichen from other forms of lichen is the continuous algal layer that grows around the circumference of the branches of the lichen. (wikipedia.org)
  • species
  • Lichens develop quite slowly with recorded growth rates of 0.01-27mm/year depending on the species. (wikipedia.org)
  • A lichen is an association between one or two fungus species and an alga or cyanobacterium (blue-green alga) that results in a form distinct from the symbionts. (britannica.com)
  • In all, about 20,000 species of lichen have been identified. (almanac.com)
  • PRINGLE: Lichens are symbioses - that means that they are made up of multiple species living together. (loe.org)
  • And generally, a lichen is one individual fungus, and living inside, embedded in the matrix of that fungus, there are algae, and maybe more than one species of algae. (loe.org)
  • There are about 20,000 known species of lichens. (wikipedia.org)
  • Wila (Bryoria fremontii), like almost all of the 23 other species of Bryoria found in North America, is a dark brown hair lichen that grow on trees (mostly conifers). (wikipedia.org)
  • In general, most species of Bryoria prefer drier forests with more open canopies than do the other genera of arboreal hair lichens (like Alectoria, Usnea, and Ramalina). (wikipedia.org)
  • Wila (along with many other lichens) is significant food source for a variety of different species of ungulates and rodents. (wikipedia.org)
  • Although each lichen thallus generally appears homogeneous, some evidence seems to suggest that the fungal component may consist of more than one genetic individual of that species. (wikipedia.org)
  • In the Lichen Flora of the Greater Sonoran Desert Region, the description given for N. homalea erroneously described the species to have depsidones, including protocetraric acid, which may be confused with salazinic acid when conducting thin-layer chromatography. (wikipedia.org)
  • Species of Niebla that contain triterpenes also contain depsides as major lichen substances, which in a species may be either divaricatic acid or sekikaic acid. (wikipedia.org)
  • benign
  • While lichen planus can be annoying, it is usually fairly benign and clears up on its own. (encyclopedia.com)
  • Lichen planus (LP) is a benign non-infectious skin condition which causes an itchy rash to appear on the skin or inside the mouth. (news-medical.net)
  • Lichen nitidus is a benign disease with no associated mortality or complications. (medscape.com)
  • Lichen striatus is a rare, benign, self-limited linear dermatosis of unknown origin that predominantly affects children. (medscape.com)
  • Lichenoid keratoses (also known as "Benign lichenoid keratosis," and "Solitary lichen planus") is a cutaneous condition characterized by brown to red scaling maculopapules, found on sun-exposed skin of extremities. (wikipedia.org)
  • water and nutrients
  • Lichens get their water and nutrients from their surrounding environment via air and rain. (fed.us)
  • The fungal component of a lichen absorbs water and nutrients from the surroundings and provides a suitable environment for the alga or cyanobacterium. (dictionary.com)
  • Lichens do not have roots that absorb water and nutrients as plants do, but like plants, they produce their own food by photosynthesis. (wikipedia.org)
  • classify lichens
  • There is still some discussion about how to classify lichens, though many taxonomists rely on genetic analyses in addition to traditional morphological data. (britannica.com)
  • patients
  • Lichen planus is a skin condition of unknown origin that produces small, shiny, flat-topped, itchy pink or purple raised spots on the wrists, forearms or lower legs, especially in middle-aged patients. (encyclopedia.com)
  • Glorioso S, Jackson SC, Kopel AJ, Lewis V, Nicotri T Jr. Actinic lichen nitidus in 3 African American patients. (medscape.com)
  • Since then, few other similar reports were published until 1990, when Friedman presented data on 35 patients with lichen spinulosus. (medscape.com)
  • In 1990, Friedman described 35 patients with lichen spinulosus. (medscape.com)
  • In most patients, lichen spinulosus remits spontaneously within 1-2 years. (medscape.com)
  • They hypothesize that lichen striatus is triggered by an immunologic reaction to an infection, which triggers methylation or demethylation of a partially silenced genomic element in predisposed patients. (medscape.com)
  • Patients with lichen myxedematosus have a long-term, disfiguring, possibly disabling disorder. (medscape.com)
  • Shan J, Ma JM, Wang R, Liu QL, Fan Y. Proliferation and Apoptosis of Peripheral Blood Mononuclear Cells in Patients with Oral Lichen Planus. (medscape.com)
  • Simon M Jr, Gruschwitz MS. In situ expression and serum levels of tumour necrosis factor alpha receptors in patients with lichen planus. (medscape.com)
  • Rhodus NL, Cheng B, Myers S, Bowles W, Ho V, Ondrey F. A comparison of the pro-inflammatory, NF-kappaB-dependent cytokines: TNF-alpha, IL-1-alpha, IL-6, and IL-8 in different oral fluids from oral lichen planus patients. (medscape.com)
  • keratosis
  • Differentiating lichen spinulosus from keratosis pilaris by microscopy may not be possible. (medscape.com)
  • Lichen spinulosus (also known as "Keratosis spinulosa") is a rare skin disorder characterized by follicular keratotic papules that are grouped into large patches. (wikipedia.org)
  • It is a variant of keratosis pilaris named for its resemblance to a patch of lichen. (wikipedia.org)
  • Follicular
  • Lichen spinulosus is an uncommon dermatosis manifested by large patches of follicular papules topped by keratotic spines, as shown in the image below. (medscape.com)
  • The classic lesion of lichen spinulosus is a keratotic plug located within the dilated follicular orifice. (medscape.com)
  • Cömert A, Akin O, Demirkesen C. Follicular mucinosis mimicking lichen spinulosus in an 11-year-old boy. (medscape.com)
  • The scalp is rarely affected by a condition known as lichen planopilaris, acuminatus, follicular lichen planus, and peripilaris, characterised by violaceous, adherent follicular scale with progressive scarring alopecia. (wikipedia.org)
  • specimens
  • Support of infectious involvement includes elevations of interleukin 1-beta in lichen striatus biopsy specimens. (medscape.com)
  • It was discovered in December 1934 by the Byrd Antarctic Expedition sledge party under Paul Siple, and so named because of the lichens and other botanical specimens obtained there. (wikipedia.org)
  • chronic
  • Lichen amyloidosis is a chronic condition without potential for malignant transformation or increase in mortality. (medscape.com)
  • Lichen planus is a T-cell mediated chronic inflammatory mucocutaneous disease of unknown cause. (scielo.br)
  • Lichen nitidus is a chronic inflammatory disease of unknown cause characterized by 1-2 mm, discrete and uniform, shiny, flat-topped, pale flesh-colored or reddish-brown papules that may appear as hypopigmented against dark skin. (wikipedia.org)
  • Lichen planus (LP) is a chronic inflammatory disease of the skin, mucous membranes and nails. (wikipedia.org)
  • histopathologic
  • Crohn's disease and lichen nitidus: a case report and comparison of common histopathologic features. (medscape.com)
  • The histopathologic and immunohistochemistry findings are similar to those in isolated lichen amyloidosis, pointing to keratin-derived amyloidosis. (medscape.com)