''Thelenella lateralis'' is a species of

corticolous This glossary of mycology is a list of definitions of terms and concepts relevant to mycology, the study of fungi. Terms in common with other fields, if repeated here, generally focus on their mycology-specific meaning. Related terms can be found ...

(bark-dwelling),

crustose lichen Crustose lichens are lichens that form a crust which strongly adheres to the Substrate (biology), substrate (soil, rock, tree bark, etc.), making separation from the substrate impossible without destruction. The basic structure of crustose lichen ...

in the family Thelenellaceae. This species is notable for its eccentric

ostiole An ''ostiole'' is a small hole or opening through which algae or fungi release their mature spores. The word is a diminutive of wikt:ostium, "ostium", "opening". The term is also used in higher plants, for example to denote the opening of the ...

(off-centre opening) and irregularly ascospores (spores with multiple chambers), which are 7–9 by 0–2-

septate In biology, a septum (Latin for ''something that encloses''; septa) is a wall, dividing a cavity or structure into smaller ones. A cavity or structure divided in this way may be referred to as septate. Examples Human anatomy * Interatrial se ...

and measure 27–32

μm The micrometre (Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a unit of length in the International System ...

by 9–10.5 μm. The

type specimen In biology, a type is a particular wikt:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally associated. In other words, a type is an example that serves to ancho ...

of ''Thelenella lateralis'' was collected from Parque da Cidade Governador José Rollemberg Leite in

Aracaju Aracaju () is the capital of the state of Sergipe, Brazil, located in the northeastern part of the country on the coast, about 350 km (217 mi) north of Salvador, Bahia, Salvador. According to the 2020 estimate, the city has 664,908 inha ...

Sergipe Sergipe (), officially State of Sergipe, is a States of Brazil, state of Brazil. Located in the Northeast Region, Brazil, Northeast Region along the Atlantic Ocean, Atlantic coast of the country, Sergipe is the smallest state in Brazil by geogra ...

, Brazil, at an elevation of about 75 m. The

thallus Thallus (: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. A thallus usually names the entir ...

is thin, metallic grey, and lacks

pseudocyphella Pseudocyphellae (singular ''pseudocyphella'') are structures in lichens that appear as tiny pores on the outer surface (the cortex) of the lichen. They are caused when there is a break in the cortex of the lichen, and the medullary hyphae extend ...

e (tiny pores on the surface) and a (a border around the thallus). The

ascomata An ascocarp, or ascoma (: ascomata), is the fruiting body (sporocarp (fungi), sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded ascus, asci, each of which typically contains four to ...

(fruiting bodies) are immersed in the bark and (pear-shaped), measuring 0.4–0.55 mm in diameter. The walls of the ascomata are only (blackened) above. The ostioles are eccentric and dark grey. The , the tissue between the asci (spore-producing structures), does not contain oil droplets, and its filaments interconnect. The asci have an ocular chamber, and the ascospores are long,

ellipsoid An ellipsoid is a surface that can be obtained from a sphere by deforming it by means of directional Scaling (geometry), scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a Surface (mathemat ...

to (spindle-shaped), hyaline (translucent), and irregularly arranged in two rows. The ascospores have rounded or pointed ends. ''Thelenella lateralis'' does not make

pycnidia A pycnidium (plural pycnidia) is an asexual fruiting body produced by mitosporic fungi, for instance in the order Sphaeropsidales ( Deuteromycota, Coelomycetes) or order Pleosporales (Ascomycota, Dothideomycetes). It is often spherical or inve ...

(small asexual fruiting bodies). Chemically, no substances were detected. ''Thelenella lateralis'' grows on smooth bark in remnants of Atlantic rainforest and is currently only known from Brazil. This is the first species in the genus '' Thelenella'' described with eccentric ostioles. It is closely related to '' Thelenella paraguayensis'', which has larger ascospores measuring 42–60 μm by 13–19 μm.

References

{{Taxonbar, from=Q108426224 Lecanoromycetes Lichen species Lichens described in 2014 Lichens of Northeast Brazil Taxa named by André Aptroot Taxa named by Marcela Cáceres