Hypogymnia canadensis | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Fungi |
Division: | Ascomycota |
Class: | Lecanoromycetes |
Order: | Lecanorales |
Family: | Parmeliaceae |
Genus: | Hypogymnia |
Species: | H. canadensis |
Binomial name | |
Hypogymnia canadensis | |
Holotype: Kispiox Valley, Canada |
Hypogymnia canadensis is a species of corticolous (bark-dwelling), foliose lichen in the family Parmeliaceae. [1] Found in western North America, it was formally described as a new species in 2007. Although Hypogymnia canadensi shares its habitat with several related species, it can be reliably identified through a combination of its morphological traits—such as narrower lobe width and smoother upper surface—and its unique chemical composition.
Hypogymnia canadensis was formally described as a new species in 2007 by the lichenologists Trevor Goward and Bruce McCune. The type specimen was collected 36 km (22 mi) north-northwest of Kispiox, British Columbia, at an elevation of 750 m (2,460 ft). The habitat is characterised as an interior cedar-hemlock zone or lower oroboreal subzone, situated at the lower end of a slope in a wet and open area of a swamp that had been disturbed or damaged. The area is an old-growth forest with Abies amabilis and Tsuga heterophylla as the predominant trees. The lichen, collected by Goward, was found growing on a Tsuga branch on 23 June 1996. [2]
Hypogymnia canadensis is a corticolous lichen, meaning it predominantly grows on tree bark. The thallus is appressed and can reach over 6 cm (2.4 in) in diameter, with a cartilaginous texture. The branching pattern ranges from isotomic (equal branching) to irregularly dichotomous , with occasional short, bud-like lobes . The upper surface is whitish to pale greenish-grey or brownish, smooth to weakly rugose (wrinkled), with minimal or sparse dark mottling. A black border (a prothallus) may sometimes be visible. [2]
The lobes that make up the thallus of Hypogymnia canadensis are contiguous to separate, soon becoming imbricate (overlapping like shingles). They have an even profile, are not intestiniform (not resembling intestines), and are 0.4 to 2.0 mm broad, with a width-to-height ratio of 1–2:1. The lobe tips are imperforate (solid). The lower surface of the lichen is also imperforate and black, with a heavily rugose texture. The inner layer, or medulla, is hollow, with the cavity ceiling ranging from pale brown to dark brown and the cavity floor from brown to dark brown, noticeable at least 5 mm back from the lobe tip. This lichen lacks asexual propagules. [2]
Apothecia (fruiting bodies) are fairly common in Hypogymnia canadensis. They are somewhat stipitate (having a short stalk) and can reach up to 6 mm in diameter. The receptacle is mainly funnel-shaped, with the stipe (stalk) being hollow or filled with white cottony hyphae. The disc of the apothecia ranges from tan to dark brown. The exterior of the thalline exciple (the outer layer of the apothecium) is pruinose , covered with a loose mass of hyphae heavily encrusted with crystals. The spores are nearly spherical to broadly ellipsoid, measuring 4.5–7.5 by 4.7–5.5 μm. [2]
Pycnidia, which are structures that produce conidia (asexual spores), are common and form black spots on the upper cortex . The conidia are rod-shaped to weakly bifusiform (spindle-shaped), measuring 3–5 by 0.4–0.6 μm. [2]
In Hypogymnia canadensis, various spot tests reveal distinct chemical reactions. The cortex shows a P+ (pale yellow) and K+ (yellow) reaction, while showing no reaction to C and KC−. The medulla, on the other hand, reacts with K+ (slowly turning reddish brown), KC+ (orange-red), but does not react to P or C. [2]
Thin-layer chromatography has identified the presence of several lichen substances in Hypogymnia canadensis. These include atranorin, physodic acid, and 3-hydroxyphysodic acid. The K+ (reddish-brown) reaction specifically associated with 3-hydroxyphysodic acid is noteworthy. As described by McCune and colleagues (2006), this colour change first appears through cracks in the cortex, followed by a gradual reddening of the medulla, visible through the translucent upper cortex. [2]
Hypogymnia canadensis can be distinguished from other species within the genus Hypogymnia by its distinct morphological and chemical characteristics. One similar species is Hypogymnia wilfiana , which shares some overlapping habitat preferences. However, H. wilfiana is characterised by a broader lobe width of 1.0–3.0 mm, compared to the narrower 0.4–2.0 mm lobes of H. canadensis. Furthermore, H. wilfiana has a more consistently blackened lower surface with a broader and more conspicuous black border on the upper surface, whereas the black border in H. canadensis is either absent or less pronounced. [3]
Another species, Hypogymnia recurva , also exhibits differences that help in distinguishing it from H. canadensis. H. recurva features recurved lobe tips, a trait not observed in H. canadensis. Additionally, H. recurva has a thicker thallus and the upper surface tends to be more rugose compared to the relatively smoother surface of H. canadensis. [3]
Both H. wilfiana and H. recurva have distinct chemical compositions that further differentiate them from H. canadensis. H. canadensis contains atranorin, physodic acid, and 3-hydroxyphysodic acid as constant lichen substances, whereas the chemical profiles of H. wilfiana and H. recurva include other secondary metabolites that can be detected through thin-layer chromatography. [3]
Hypogymnia canadensis is found in the cool, moist conifer forests of the coastal mountains in western North America. Its range extends from southeastern Alaska to northern Oregon, reaching inland to southeastern British Columbia. In the southern part of its range, it is relatively rare and typically absent from lower elevations. In Oregon, it is found at elevations between 730 and 1,400 m (2,400 and 4,590 ft), whereas in coastal Alaska, it can be found near sea level. [2] Since its original publication in 2007, the lichen has been documented from several locations across coastal southern Alaska, typical growing on conifers and Betula . [4]
The habitats occupied by H. canadensis experience cool, wet winters, often with substantial snowfall, and mild, relatively dry summers. [2]
Hypogymnia is a genus of foliose lichens in the family Parmeliaceae. They are commonly known as tube lichens, bone lichens, or pillow lichens. Most species lack rhizines that are otherwise common in members of the Parmeliaceae, and have swollen lobes that are usually hollow. Other common characteristics are relatively small spores and the presence of physodic acid and related lichen products. The lichens usually grow on the bark and wood of coniferous trees.
A spot test in lichenology is a spot analysis used to help identify lichens. It is performed by placing a drop of a chemical reagent on different parts of the lichen and noting the colour change associated with application of the chemical. The tests are routinely encountered in dichotomous keys for lichen species, and they take advantage of the wide array of lichen products produced by lichens and their uniqueness among taxa. As such, spot tests reveal the presence or absence of chemicals in various parts of a lichen. They were first proposed as a method to help identify species by the Finnish lichenologist William Nylander in 1866.
Hypogymnia occidentalis, commonly known as the lattice tube lichen, is a species of foliose lichen in the family Parmeliaceae. It is found in North America, where it grows on the lower trunks of conifers, particularly Douglas-fir.
Hypogymnia congesta is a rare species of foliose lichen in the family Parmeliaceae. Found in China, it was formally described as a new species in 2003. The lichen grows on the bark and wood of conifers and bamboo. Hypogymnia congesta has a brown to brownish-grey foliose thallus measuring up to 8 cm (3.1 in) long or broad, with a cartilage-like texture. The lichen is chemically distinct, containing physodic acid and virensic acid; the latter substance is otherwise unknown from genus Hypogymnia.
Punctelia hypoleucites, commonly known as the southwestern speckled shield lichen, is a species of foliose (leafy) lichen in the family Parmeliaceae. First formally described by Finnish botanist William Nylander as a species of Parmelia, it was transferred to the genus Punctelia in 1982. The lichen is found in Africa, North America, and South America, where it grows on the bark of both hardwood and coniferous trees. Its greenish-grey thallus is covered with tiny white pseudocyphellae – minute holes in the thallus surface that facilitate gas exchange. Some macroscopic features that help distinguish this species from other related members of the genus include the presence and the structure of the apothecia, the absence of asexual surface propagules, and the light brown color of the thallus undersurface. Chemically, the presence of lecanoric acid in the medulla and atranorin in the cortex help distinguish it from lookalikes.
Hypogymnia krogiae, commonly known as the freckled tube lichen, is a species of foliose lichen in the family Parmeliaceae. Found in North America, it was described as a new species in 1973 by Karl Ohlsson. The type specimen was collected near Cheat Bridge, West Virginia by Mason Hale in 1956.
Hypogymnia flavida is a species of foliose lichen in the family Parmeliaceae. It is found in mountainous locations of east Asia, where it grows on the bark and wood of woody plants. It has a relatively large yellowish thallus.
Parmelia fraudans is a species of foliose lichen in the family Parmeliaceae. It is found in Europe and North America, where it grows on rocks.
Hypogymnia wilfiana is a species of foliose lichen in the family Parmeliaceae. It is found in western North America, where it grows on conifer trees.
Solorina crocea, commonly known as the orange chocolate chip lichen, is a species of terricolous (ground-dwelling) and foliose (leafy) lichen in the family Peltigeraceae. The lichen, which was first formally described by Carl Linnaeus in 1753, has an arctic–alpine and circumpolar distribution and occurs in Asia, Europe, North America, and New Zealand. It generally grows on the bare ground in sandy soils, often in moist soil near snow patches or seepage areas. Although several forms and varieties of the lichen have been proposed in its history, these are not considered to have any independent taxonomic significance.
Hypogymnia pruinoidea is a species of foliose lichen in the family Parmeliaceae. Found in China, it was formally described as a new species in 2012 by Xin-Li Wei and Jiang-Chun Wei. The type specimen was collected from Mt. Taibaishan (Shaanxi) at an elevation of 2,800 m (9,200 ft), where it was found growing on the trunk of Abies. It is only known to occur at this location, a cool and moist montane environment supporting lichen-rich forests and woodlands. The species epithet refers to the pruinose upper thallus surface and lobe tips.
Hypogymnia capitata is a species of foliose lichen in the family Parmeliaceae. Found in high-elevation conifer forests in Sichuan Province, China, it was described as a new species in 2014. The lichen is characterized by its capitate terminal soralia, brownish lobes with white cavities, and the presence of olivetoric acid. This lichen is distinguished from similar species by its specific morphological, chemical, and habitat characteristics.
Hypogymnia nitida is a species of foliose lichen in the family Parmeliaceae. It has a glossy dark brown upper surface and a strongly wrinkled, convoluted lower surface. Found in China, it was described as a new species in 2014.
Hypogymnia pendula is a rare species of foliose lichen in the family Parmeliaceae. It is characterised by its pendulous (hanging) growth form and distinct chemical composition.
Hypotrachyna constictovexans is a little-known species of foliose lichen in the family Parmeliaceae. Known only from a single specimen collected in 1976, it is found in the highlands of Peru. Its thallus can grow over 5 cm wide, featuring long, straight, and separate lobes that are highly convex and tube-like, with a pale grey, slightly shiny upper surface adorned with cylindrical isidia.
Hypogymnia amplexa is a species of corticolous (bark-dwelling), foliose lichen in the family Parmeliaceae. It is found in the western United States and Canada.
Peltigera cinnamomea, commonly known as the cinnamon-pelt lichen, is a muscicolous (moss-dwelling), leafy lichen in the family Peltigeraceae. The Canadian lichenologist Trevor Goward formally described the species in 1995. The lichen is found in northwestern North America's forested regions, particularly in the unique montane and subalpine forest communities of the northern Rocky Mountains. Peltigera cinnamomea grows under prolonged snow cover, surviving well into spring. This trait distinguishes it from many other Peltigera species in similar North American forest ecosystems.
Tuckermannopsis orbata, commonly known as the variable wrinkle lichen, is a species of foliose lichen in the family Parmeliaceae. It is a small cetrarioid lichen, an informal growth form category that denotes lichens with erect, foliose thalli, and apothecia and pycnidia on the margins of the ruffled lobes. Tuckermannopsis orbata is found in Asia and North America, growing primarily on the wood and bark of mostly birch and coniferous tree branches and twigs.
Sticta torii is a rare species of corticolous (bark-dwelling), lichen in the family Peltigeraceae. Found in northwestern North America, it was formally described as a new species in 2018 by the lichenologists Antoine Simon and Trevor Goward, from specimens collected in Alaska. The species epithet honours the Norwegian lichenologist Tor Tønsberg, "in recognition of his outstanding, vigorous contribution to lichenology".
Xanthoparmelia cranfieldii is a species of foliose lichen in the family Parmeliaceae, first described by John Elix in 2003. It is known only from its type locality in Western Australia.