foliicolous
Foliicolous refers to the growth habit of certain lichens, algae, and fungi that prefer to grow on the leaves of vascular plants
Vascular plants (), also called tracheophytes () or collectively Tracheophyta (), form a large group of land plant ...
(leaf-dwelling)
lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Thelenellaceae. Found in India, it was formally described as a new species in 2006 by Athokpam Pinokiyo and Krishna Pal Singh. The
type specimen
In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...
was collected by the first author in a
tropical
The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in
the Southern Hemisphere at S. The tropics are also referred to ...
forest along the Assam-Linzey road in the
East Sikkim district
Gangtok District, formerly the East Sikkim 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 Si ...
; here it was found growing on the leaves of a small '' Schima wallichii'' tree. It appears to be
endemic
Endemism is the state of a species being found 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 found elsew ...
to the
Sikkim
Sikkim (; ) is a state in Northeastern India. It borders the Tibet Autonomous Region of China in the north and northeast, Bhutan in the east, Province No. 1 of Nepal in the west and West Bengal in the south. Sikkim is also close to the Siligur ...
region of India.
The lichen has a greyish-brown, verrucose (warted)
thallus
Thallus (plural: 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. Many of these organisms wer ...
photobiont
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.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 ...
from family
Chlorococcaceae
Chlorococcaceae is a family of green algae, in the order Chlamydomonadales.
List of genera
* '' Apodochloris''
* '' Bracteacoccus''
* '' Chlorococcopsis''
* '' Chlorococcum''
* '' Chlorohippotes''
* '' Chlorotetraedron''
* '' Closteridium''
* ' ...
with rounded cells measuring 6–12
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 ...
in diameter, and occurring in groups of 5–18 cells.