Chrysothrix placodioides
species of fungus
Chrysothrix placodioides is a rare species of crustose lichen in the family Chrysotrichaceae. First described by Göran Thor in 1988, this Brazilian endemic species is distinguished by its placodioid thallus structure and distinctive chemical and morphological characteristics.
Taxonomy
Chrysothrix placodioides was described based on collections made in 1894 by the botanist Gustaf Malme in Serra da Chapada, Mato Grosso, Brazil. The species is morphologically similar to Chrysothrix pavonii but differs by its placodioid thallus, non-byssaceous medulla, and distinctively larger spores. The species epithet placodioides alludes to its placodioid (crust-like, tightly adherent) growth form.
Description
The thallus of Chrysothrix placodioides is dark yellow and placodioid, forming tightly attached, smooth patches 0.5–2 cm in diameter and about 0.1–0.4 mm thick. It lacks both a prothallus and a true cortex. The medulla is loosely structured, cretaceous (chalky), and dark yellow, lacking calcium oxalate crystals. The photobiont consists of unicellular green algae belonging to Chlorococcaceae, approximately 5–10 μm in diameter.
Apothecia (fruiting bodies) are abundant and distinctive, with a brownish-orange, flat to convex disc measuring 0.2–1.0 mm in diameter.
“Chrysothrix placodioides” enters the record as species of fungus. Crown Archives preserves that source wording while asking what Chrysothrix, placodioides and species can confirm, complicate or overturn.
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“Chrysothrix placodioides” is worth following because a concise public description often conceals a longer documentary argument. Here, Chrysothrix, placodioides and species provides the most credible route into that argument.
Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Jan 5, 2026. The linked authority identifier is Q21246320. The first chronological checks are 1988 and 1894.
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This entry incorporates text from “Chrysothrix placodioides” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.