Palaeochiropterygidae is a

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of extinct

bat Bats are mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most ...

s. It was originally erected by the Swiss naturalist

Pierre Revilliod Pierre Revilliod (1883–1954) was a Swiss naturalist. From 1927–1953 Revilliod was a curator and researcher at the Natural History Museum of Geneva. He is best known for his work on fossil bats Bats are mammals of the order Chiro ...

in 1917 after discoveries of '' Palaeochiropteryx'' fossils from the

Messel Pit The Messel pit (german: Grube Messel) is a disused quarry near the village of Messel (Landkreis Darmstadt-Dieburg, Hesse) about southeast of Frankfurt am Main, Germany. Bituminous shale was mined there. Because of its abundance of well-preserved ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

. Palaeochiropterygidae was merged into

Archaeonycteridae Archaeonycteridae (formerly spelled Archaeonycterididae) is a Family (biology), family of extinct bats. It was originally erected by the Swiss people, Swiss naturalist Pierre Revilliod as Archaeonycterididae to hold the genus ''Archaeonycteris''. ...

by Kurten and Anderson in 1980, but modern authorities specializing in bat fossils maintain the distinction between the two. It was classified to the unranked clade Microchiropteramorpha by Smith ''et al.'' in 2007. They existed from the

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 ...

to the

Lutetian The Lutetian is, in the geologic timescale, a stage or age in the Eocene. It spans the time between . The Lutetian is preceded by the Ypresian and is followed by the Bartonian. Together with the Bartonian it is sometimes referred to as the ...

ages of the Middle

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'', " ...

epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided by ...

(55.8 to 40.4 million years ago).

Paleobiology

Two species of Palaeochiropterygidae, ''Palaeochiropteryx tupaiodon'' and ''P. spiegeli'', are known from complete skeletons from the famous Messel Pit fossil deposits in Germany. ''Palaeochiropteryx tupaiodon'' is the most common mammal found at Messel. All other species belonging to Palaeochiropterygidae are known only from isolated teeth and jaw fragments from

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

Turkey Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a transcontinental country located mainly on the Anatolian Peninsula in Western Asia, with a small portion on the Balkan Peninsula in ...

, and possibly North America. At Messel, the two species of ''Palaeochiropteryx'' are hypothesized to have occupied similar niches to living hipposiderids and rhinolophids that forage close to the ground and among vegetation. Wings with low aspect ratio and

wing loading In aerodynamics, wing loading is the total mass of an aircraft or flying animal divided by the area of its wing. The stalling speed of an aircraft in straight, level flight is partly determined by its wing loading. An aircraft or animal with a ...

and preserved stomach contents of small

moth Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of w ...

s and

caddisflies The caddisflies, or order Trichoptera, are a group of insects with aquatic larvae and terrestrial adults. There are approximately 14,500 described species, most of which can be divided into the suborders Integripalpia and Annulipalpia on the ...

support the idea that these palaeochiropterygids were slow but maneuverable fliers. The widespread distribution of Palaeochiropterygidae among the northern continents in the early and middle Eocene conflicts with the known

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines * Morphology (archaeology), study of the shapes or forms of artifacts * Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ...

of ''P. tupaiodon'' and ''P. spiegeli'', however, suggesting that other species of palaeochiropterygids had body plans much more suitable to long distance dispersal.

Evolutionary relationships

Palaeochiropterygidae are generally considered to be the most advanced of the early bat families.

Phylogenetic analyses In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

have consistently shown Palaeochiropterygidae to be the closest relatives of the living, or

crown A crown is a traditional form of head adornment, or hat, worn by monarchs as a symbol of their power and dignity. A crown is often, by extension, a symbol of the monarch's government or items endorsed by it. The word itself is used, partic ...

, groups of bats. Most phylogenetic analyses only include species of fossil bats known from complete skeletons, so relationships of species within Palaeochiropterygidae are currently unknown. Both '' Matthesia'' and '' Cecilionycteris'' may be junior synonyms of ''Palaeochiropteryx''. ''Stehlinia'' has been previously considered to be a member of the superfamily Vespertilionoidea, possibly aligned with

Natalidae The family Natalidae, or funnel-eared bats, are found from Mexico to Brazil and the Caribbean islands. The family has three genera, '' Chilonatalus'', '' Natalus'' and '' Nyctiellus''. They are slender bats with unusually long tails and, as th ...

or Kerivoulidae, but is now more commonly recognized as a palaeochiropterygid. ''Stehlinia'', along with '' Lapichiropteryx'' and '' Anatolianycteris'', possesses a very simple lower fourth premolar compared to other palaeochiropterygids and a close relationship between those three species has been proposed.

Genera

It contains the following genera. The list may be incomplete or inaccurate: * '' Anatolianycteris'' Jones ''et al.'', 2018 **'' Anatolianycteris insularis'' Jones ''et al.'', 2018 - Orhaniye Basin (

*'' Cecilionycteris'' Heller, 1935 :*'' Cecilionycteris prisca'' Heller, 1935 -

Geiseltal The Geisel valley (german: Geiseltal) is a valley in Saxony-Anhalt, Germany, situated west of Merseburg, Saalekreis district. It is named after the River Geisel (river), Geisel which rises in Mücheln (Geiseltal), Mücheln and is a tributary of the ...

(

*'' Lapichiropteryx'' Tong, 1997 :*'' Lapichiropteryx xiei'' Tong, 1997 - Yuanqu Basin (

?), China * '' Matthesia'' Sigé and Russell, 1980 ** ''Matthesia'' ''insolita'' Sigé and Russell, 1980 - Geiseltal (Lutetian), Germany ** '' Matthesia germanica'' Sigé and Russell, 1980 - Geiseltal (Lutetian), Germany *'' Microchiropteryx'' Smith ''et al.'', 2007 :*'' Microchiropteryx folieae'' Smith ''et al.'', 2007 - Vastan Lignite Mines (Ypresian),

*'' Palaeochiropteryx'' Revilliod, 1917 :*'' Palaeochiropteryx tupaiodon'' Revilliod, 1917 -

(Lutetian), Germany :*'' Palaeochiropteryx spiegeli'' Revilliod, 1917 - Messel Pit (Lutetian), Germany * '' Stehlinia'' Revilliod, 1919 **'' Stehlinia gracilis'' (Revilliod 1922) - Unknown locality,

Quercy Quercy (; oc, Carcin , locally ) is a former province of France located in the country's southwest, bounded on the north by Limousin, on the west by Périgord and Agenais, on the south by Gascony and Languedoc, and on the east by Rouergue and ...

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

** '' Stehlinia alia'' Maitre 2014 - Cuzal, Quercy ( MP 13), France ** '' Stehlinia bonisi'' Sige 1990 - Le Garouillas, Quercy ( MP 25), France ** '' Stehlinia minor'' (Revilliod 1922) - Unknown locality, Quercy, France ** '' Stehlinia pusilla'' (Revilliod 1922) -

Egerkingen Egerkingen is a municipality in the district of Gäu in the canton of Solothurn in Switzerland. History Egerkingen is first mentioned in 1201 as ''in Egrichen''. In 1212 it was mentioned as ''in Egerchingen''. Geography Egerkingen has an ar ...

( MP 14?), Switzerland ** '' Stehlinia quercyi'' (Revilliod 1922) - Unknown locality, Quercy, France ** '' Stehlinia revilliodi'' Maitre 2014 - Cuzal, Quercy (MP 13), France ** '' Stehlinia rutimeyeri'' (Revilliod 1922) - Egerkingen (MP 14?), Switzerland

References

{{Taxonbar, from=Q7126402 Bat families Eocene bats Eocene first appearances Eocene extinctions