''Nanotermes'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

termite Termites are small insects that live in colonies and have distinct castes (eusocial) and feed on wood or other dead plant matter. Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blatto ...

s in the

Isoptera Termites are small insects that live in colonies and have distinct castes (eusocial) and feed on wood or other dead plant matter. Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blattod ...

family

Termitidae Termitidae is the largest family of termites whose members are commonly known as the higher termites. They are evolutionarily the most specialised termite group, with their highly compartmentalized hindgut lacking the flagellated protozoans comm ...

known from only one

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

fossil found in

amber Amber is fossilized tree resin that has been appreciated for its color and natural beauty since Neolithic times. Much valued from antiquity to the present as a gemstone, amber is made into a variety of decorative objects."Amber" (2004). In ...

of the Cambay Basin (

Gujarat Gujarat (, ) is a state along the western coast of India. Its coastline of about is the longest in the country, most of which lies on the Kathiawar peninsula. Gujarat is the fifth-largest Indian state by area, covering some ; and the ninth ...

, India). The genus contains a single described species, ''Nanotermes isaacae'' placed tentatively in the subfamily

Termitinae Termitinae is a subfamily of termites; ''Amitermes'' and certain other genera (indicated here with a *) have previously been placed in the Amitermitinae Amitermitinae is a disputed subfamily of "higher termites" now often merged with the sub ...

History and classification

''Nanotermes'' is known from a single fossil, the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of sever ...

adult, which is an

inclusion Inclusion or Include may refer to: Sociology * Social inclusion, aims to create an environment that supports equal opportunity for individuals and groups that form a society. ** Inclusion (disability rights), promotion of people with disabiliti ...

in a transparent chunk of Cambay amber. The amber specimen, "Tad-262", is currently housed in the fossil collection of the

Birbal Sahni Birbal Sahni FRS (14 November 1891 – 10 April 1949) was an Indian paleobotanist who studied the fossils of the Indian subcontinent. He also took an interest in geology and archaeology. He founded what is now the Birbal Sahni Institute of Pa ...

Institute of Palaeobotany in

Lucknow Lucknow (, ) is the capital and the largest city of the Indian state of Uttar Pradesh and it is also the second largest urban agglomeration in Uttar Pradesh. Lucknow is the administrative headquarters of the eponymous district and division ...

, India. The holotype is composed of a mostly complete adult of indeterminate sex and minute overall size. Cambay amber dates to between 50 and 52 million years old, placing it in the Early to Mid

Ypresian In the geologic timescale the Ypresian is the oldest age or lowest stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by the Eocene Lutetian Age. The Ypresian ...

age of the Eocene, and was preserved in a

brackish Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estu ...

shore environment. The amber formed from a dammar type resin, which is produced mainly by trees in the family Dipterocarpaceae. The holotype specimen was recovered from the Tadkeshwar lignite mine, located in Gujarat State, during a collecting trip on 17–22 January 2010. The fossil was first studied by paleoentomologists Michael S. Engel and David Grimaldi, both of the American Museum of Natural History. Engel and Grimaldi's 2011

type description A species description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have be ...

of the new genus and species was published in the online journal ''

ZooKeys ''ZooKeys'' is a peer-reviewed open access scientific journal covering zoological taxonomy, phylogeny, and biogeography. It was established in 2008 and the editor-in-chief is Terry Erwin (Smithsonian Institution). It is published by Pensoft P ...

''. The genus name ''Nanotermes'' was coined as a combination of the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

word ''nanos'' meaning "small" and '' Termes'', the type genus of the

. This is in reference to the size of the adult, which is noted as possibly the smallest termite adult known. The specific epithet ''isaacae'' is in honor of Charlotte Isaac, who discovered the holotype and "many other interesting inclusions". ''Nanotermes'' is the oldest member of the Termitidae to be described to date, with the prior oldest being from the Late Oligocene, 20 million years younger than the Cambay ambers.

Description

''Nanotermes'' adults have a coloration which ranges from dark brown on the majority of the head and abdomen, lightening to brown on the

pronotum The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum ( dorsal), the prosternum (ventral), and the propleuron (lateral) on e ...

, labrum, and postclypeus. The color further pales on the legs and antennae to a light brown, and to a white strip along the labrum's apical margin. The holotype has a length of and sports wings that are . Adults have a slightly oval head which is longer than wide with a sparse distribution of

seta In biology, setae (singular seta ; from the Latin word for " bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. ...

e. The antennae are generally moniliform in structure, thus having an appearance similar to a string of beads. They are composed of 12 segments (flagellomeres), which gradually increase in diameter from the base to the antenna tip. This is the lowest number of antennal segments found in the Termitidae, with some modern Syntermitinae genera coming close, having 13 segments. The presence of three pairs of spurs on the tibia is considered unusual for the Termitinae, leading Engel and Grimaldi to leave the fossil's placement among the Termitinae tentative.

References

{{Taxonbar, from=Q6964160 Termite genera Eocene insects Insects described in 2011 Fossil taxa described in 2011 Cenozoic insects of Asia Taxa named by Michael S. Engel