''Thelenella indica'' is a species of foliicolous (leaf-dwelling)

lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), m ...

in the family Thelenellaceae. Found in India, it was

formally described A species description is a formal scientific description of a newly encountered species, typically articulated through a scientific publication. Its purpose is to provide a clear description of a new species of organism and explain how it differ ...

as a new species in 2006 by Athokpam Pinokiyo and Krishna Pal Singh. 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 ...

was collected by the first author in a

tropical The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...

forest along the Assam-Linzey road in the

East Sikkim district Gangtok District is an administrative district of the Indian state of Sikkim. It was renamed in 2021 as a result of administrative reorganisation of the state, which also saw three subdivisions of the East Sikkim district spawned off as a separ ...

; here it was found growing on the leaves of a small ''

Schima wallichii ''Schima wallichii'', commonly known as the needlewood or Chinese guger tree, is a species of evergreen tree in the tea family, Theaceae. ''Schima wallichii'' is native to a wide area of China and tropical Asia. It grows tall. File:Chilaune.j ...

'' tree. It appears to be

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the

Sikkim Sikkim ( ; ) is a States and union territories of India, state in northeastern India. It borders the Tibet Autonomous Region of China in the north and northeast, Bhutan in the east, Koshi Province of Nepal in the west, and West Bengal in the ...

region of India. The lichen has a greyish-brown, verrucose (warted)

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 ...

lacking a

cortex Cortex or cortical may refer to: Biology * Cortex (anatomy), the outermost layer of an organ ** Cerebral cortex, the outer layer of the vertebrate cerebrum, part of which is the ''forebrain'' *** Motor cortex, the regions of the cerebral cortex i ...

. The

photobiont A lichen ( , ) is a hybrid colony of algae or cyanobacteria living symbiotically among filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualistic relationship.

partner of ''Thelenella indica'' is a species of

green alga The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ( ...

from family

Chlorococcaceae Chlorococcaceae is a family of green algae, in the order Chlamydomonadales. They are mostly soil-dwelling algae. Many members of this group produce lipids and secondary carotenoids. The Chlorococcaceae consists mostly of coccoid (single, nonmoti ...

with rounded cells measuring 6–12

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 ...

in diameter, and occurring in groups of 5–18 cells.

References

Lecanoromycetes Lichen species Lichens described in 2006 Lichens of India {{Lecanoromycetes-stub