Glisachaemus is an extinct monotypic

Monotypic

In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

 genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of planthopper

Planthopper

A planthopper is any insect in the infraorder Fulgoromorpha within the Hemiptera. The name comes from their remarkable resemblance to leaves and other plants of their environment and from the fact that they often "hop" for quick transportation in a similar way to that of grasshoppers. However,...

 in the Cixiidae

Cixiidae

Cixiidae is a family of fulgoroid insects, one of many families commonly known as planthoppers, distributed worldwide and comprising more than 2,000 species from over 150 genera...

 subfamily Cixiinae and at present, it contains the single species Glisachaemus jonasdamzeni. The genus is solely known from the Early Eocene Baltic amber

Baltic amber

The Baltic region is home to the largest known deposit of amber, called Baltic amber or succinite, with about 80% of the world's known amber found there. It dates from 44 million years ago...

 deposits in the Baltic Sea

Baltic Sea

The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...

 region of Europe.

History and classification

Glisachaemus jonasdamzeni is known only from one fossil, the holotype, number "No. 20067". It is a single male individual preserved in a clear yellow amber specimen with several unidentified Collembola associated and a parasitic mite on its dorsal surface. The specimen is complete, with only the right foreleg detached, but associated close by the body. The male was entombed while in flight posture

Insect flight

Insects are the only group of invertebrates known to have evolved flight. Insects possess some remarkable flight characteristics and abilities, still far superior to attempts by humans to replicate their capabilities. Even our understanding of the aerodynamics of flexible, flapping wings and how...

, with both the hemelytra

Elytron

An elytron is a modified, hardened forewing of certain insect orders, notably beetles and a few of the true bugs ; in most true bugs, the forewings are instead called hemelytra, as only the basal half is thickened while the apex is membranous...

 and hindwings spread. The amber is currently residing in the private collection of Jonas Damzen, Vilnius, Lithuania. The specimen is to be donated to the Museum of Amber Inclusions, University of Gdańsk in Gdańsk

Gdansk

Gdańsk is a Polish city on the Baltic coast, at the centre of the country's fourth-largest metropolitan area.The city lies on the southern edge of Gdańsk Bay , in a conurbation with the city of Gdynia, spa town of Sopot, and suburban communities, which together form a metropolitan area called the...

, Poland

Poland

Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...

 with the accession number "MIB 5075". G. jonasdamzeni was first studied by Jacek Szwedo, with his 2007 type description being published in the journal Alavesia. The generic

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 name was coined by Jacek Szwedo as a combination of the Old Prussian

Old Prussian language

Prussian is an extinct Baltic language, once spoken by the inhabitants of the original territory of Prussia in an area of what later became East Prussia and eastern parts of...

 word glisis, meaning "amber", and Flachaemus, a modern planthopper genus. This is in reference preservation of the type specimen and the genus that Glisachaemus is possibly related. The specific epithet "jonasdamzeni" was designated by Jacek Szwedo in honor of the collector of the specimen, Jonas Damzen.

Description

Glisachaemus jonasdamzeni is 3.85 millimetre (0.151574803149606 in) in length and has a wing span of 8 millimetre (0.31496062992126 in). Though similar to the related genus Flachaemus of South Africa

South Africa

The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

, there are several notable differences between the genera. Flachaemus has an upper surface

Vertex (anatomy)

In arthropod and vertebrate anatomy, the vertex refers to the upper surface of the head.In humans, the vertex is formed by four bones of the skull: the frontal bone, the two parietal bones, and the occipital bone...

of the head which is flat with no border. Glisachaemus in contrast has front edge of upper surface delimited by transverse carina. The upper surface in Glisachaemus is shorter than its width, while in Flachaemus the surface is twice as long as it is broad. Also noted is the grouping of spines along the hind tibia of the genera, in Flachaemus the apical spines are grouped while in Glisachaemus they are not.