''Acanthothecis verrucosa'' is a species of
lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.[Graphidaceae
The Graphidaceae are a family of lichens in the order Ostropales.
Distribution and ecology
The vast majority of Graphidaceae species are restricted to the tropics. Most Graphidaceae species are epiphytic (i.e. they grow only on plants).
Gener ...]
.
It is found in southern Vietnam, where it grows on smooth-barked trees in
tropical forests. The lichen is characterized by its olive-green, thallus and the presence of
psoromic acid
Psoromic acid is a β-orcinol depsidone with the molecular formula C18H14O8. Psoromic acid inhibits herpes simplex viruses type 1 and type 2. Furthermore, it inhibits the RabGGTase. Psoromic acid occurs in antarctic lichens
A lichen ( , ) ...
. This species can easily be confused with similar lichens, but it can be distinguished by its specific
morphological and chemical features.
Taxonomy
''Acanthothecis verrucosa'' was first
described by Santosh Joshi,
, and Jae-Seoun Hur as a new species in 2017. The
species name, ''verrucosa'', is derived from the
Latin word for "warts" and refers to the wart-like appearance of the lichen's thallus. The
type specimen was collected from tree bark in
Cát Tiên National Park, Vietnam, in December 2015.
Description
This lichen features a hard, glossy thallus that is olive-green, green, or dark green, and forms large patches. Its cortex is 25–45
μm
The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...
thick, and it hosts a ''
Trentepohlia'' (
green alga
The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as ...
l) . The
medulla of the lichen is white and crystalline.
The are irregular to shortly and labiate, with white labia that can be straight or internally folded. The is mostly concealed to slightly exposed and has a white surface. The ascospores are
hyaline
A hyaline substance is one with a glassy appearance. The word is derived from el, ὑάλινος, translit=hyálinos, lit=transparent, and el, ὕαλος, translit=hýalos, lit=crystal, glass, label=none.
Histopathology
Hyaline cartilage is ...
,
ellipsoid
An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation.
An ellipsoid is a quadric surface; that is, a surface that may be defined as the ...
al, and , measuring 35–70 μm long and 15–20 μm wide.
In terms of standard chemical
spot tests, ''Acanthothecis verrucosa'' tests negative for K and C reactions, while showing a positive yellow reaction for PD.
Psoromic and
subpsoromic acid
Subpsoromic acid is a depsidone with the molecular formula C17H12O8 which has been isolated from the lichen '' Ocellularia praestans''.
References
Lichen products
Oxygen heterocycles
Carboxylic acids
Dioxepines
Heterocyclic compounds w ...
s have been identified through
thin-layer chromatography.
''Acanthothecis verrucosa'' is most similar to ''
Acanthothecis consocians'' due to the production of psoromic acid. However, it differs in having muriform ascospores. Other species within the genus, such as ''
A. nivalis'' and ''
A. dialeuca'', have different morphological and anatomical characteristics that separate them from ''A. verrucosa''. The presence of psoromic acid, muriform ascospores, and the olive-green, verrucose thallus help to distinguish this species from similar lichens.
Habitat and distribution
''Acanthothecis verrucosa'' is native to the tropical forests of Cát Tiên National Park in southern Vietnam. It is commonly found growing in large patches on thick and relatively smooth-barked trees. The lichen often coexists with other graphidioid and thelotremoid species around the tree trunks.
References
{{Taxonbar, from=Q107463931
verrucosa
''Verrucosa'' is a genus of orb-weaver spiders first described by Henry McCook in 1888. It contains almost fifty described species, most of which live in South America. The only species in the United States is the arrowhead spider.
Species
i ...
Lichen species
Lichens described in 2017
Lichens of Indo-China
Taxa named by Dalip Kumar Upreti
Taxa named by Jae-Seoun Hur