Terana caerulea
Description
Terana caerulea (or Terana coerulea) is a saprobic crust fungus in the family Phanerochaetaceae. This corticioid (crust-like) fungus is a real beauty, especially when young and fresh with a bright cobalt blue appearance. The rounded fruit bodies coalesce to form irregular large patches with either smooth or slightly bumpy or warty fertile surfaces that are usually finely velvety.
This fungus is usually found in warm, damp hardwood forests on the undersides of fallen logs and branches of deciduous trees.
Terana caerulea has a worldwide distribution in warmer climates and has been reported from Asia, Africa, New Zealand, North America, the Canary Islands, Europe, Taiwan, Thailand, and Turkey.
Old specimens turn dark blue and eventually almost black.
Common names: Cobalt Crust Fungus, Velvet Blue Spread.
Mushroom Identification
Fruitbody
Intensely dark blue resupinate rounded fruitbodies that coalesce to form irregular large patches with either smooth or slightly bumpy or warty fertile surfaces that are usually finely velvety. This is a very thin crust fungus, generally much less than 1 mm in thickness.
When moist, the texture of these crust fungi is softish with a waxy feel, and the outer margins are pale, sometimes whitish, and finely fringed. Old specimens turn dark blue and eventually almost black.
Hyphal System
Monomitic (containing only generative, branched tubular hyphae typically 3 to 5µm in diameter); Clamps are present.
Spores
Ellipsoidal, smooth, thin-walled, 6.5-9.0 x 4.5-5.5µm; hyaline or very nearly so; inamyloid.
Spore Print
Creamy white; sometimes a bluish tinge is detectable.
Odor and Taste
No noticeable odor; tough when dry, waxy when wet, but quite tasteless.
Habitat & Ecological Role
Saprobic, on dead hardwood trees and fallen branches, particularly Ash Fraxinus excelsior.
Similar Species
Stereum subtomentosum is sometimes entirely resupinate and then similar in form to Cobalt Crust, but it is usually various shades of grayish-orange.
History
Cobalt Crust fungus was described in 1779 by French naturalist Jean-Baptiste Pierre Antoine de Monet, Chevalier de Lamarck (1744 - 1829), who gave it the name Byssus caerulea.
The various other designations were subsequently employed until in 1828 Fries classified it as Thelephora violascens variety coerulea. According to rule 13.1.d. of the International Code of Botanical Nomenclature, valid publication of fungal names is treated as beginning with Fries's publication of "Systema Mycologicum" in 1821 and following years. This means that the correct species name is coerulea, not caerulea. Both names are found frequently in the literature. Strangely enough, Lamarck's name Byssus has now come to be applied to a plant genus - a fundamentally different organism.
Its currently-accepted scientific name Terana caerulea dates from a, 1891 publication by German botanist and mycologist Otto Kuntze (1843 -1907).
Synonyms of Teranea caerulea include Byssus phosphorea L., Byssus caerulea Lam., Auricularia phosphorea Sowerby, Thelephora caerulea (Lam.) Schrad. ex DC., Thelephora indigo Schwein., Corticium caeruleum (Lam.) Fr., and Pulcherricium caeruleum (Lam.) Parmasto.
The specific epithet caerulea means dark blue.
Terana caerulea Chemistry
The blue pigment of this fungus was shown to be a mixture of polymers structurally related to thelephoric acid.
When activated by external treatments such as high temperature (42 °C (108 °F)), exposure to vapors of toxic solvents, or contact with a water-toluene mixture, T. caerulea produces an antibiotic named cortalcerone (2-hydroxy-6H-3-pyrone-2-carboxaldehyde hydrate), that inhibits the growth of Streptococcus pyogenes. The metabolic biosynthesis of this compound starting from the initial precursor glucose has also been studied.
Compounds with so-called "benzobisbenzofuranoid" skeletons have been isolated and identified from T. caerulea, namely, corticins A, B, and C.
Photo sources:
Photo 1 - Author: Martin Bemmann (CC BY 3.0)
Photo 2 - Author: Strobilomyces (CC BY-SA 3.0)
Photo 3 - Author: Björn S... (CC BY-SA 2.0)
Photo 4 - Author: Björn S... (CC BY-SA 2.0)
Photo 5 - Author: Ian Dodd (kk) (www.kundabungkid.com) Australia (kundabungkid) (CC BY-SA 3.0)
