Leptictidium is an extinct genus of small mammals that were likely bipedal. Comprising eight species, they resembled today's bilbies, bandicoots, and elephant shrews. They are especially interesting for their combination of characteristics typical of primitive eutherians with highly specialized adaptations, such as powerful hind legs and a long tail which aided in locomotion. They were omnivorous, their diet a combination of insects, lizards and small mammals. Leptictidium and other leptictids are not placentals, but are non-placental eutherians, although closely related. They appeared in the Lower Eocene, a time of warm temperatures and high humidity, roughly fifty million years ago. Although they were widespread throughout Europe, they became extinct around thirty-five million years ago with no descendants, probably because they were adapted to live in forest ecosystems and were unable to adapt to the open plains of the Oligocene.
The Messel pit is a disused quarry near the village of Messel about 35 km (22 mi) southeast of Frankfurt am Main, Germany. Bituminous shale was mined there. Because of its abundance of well-preserved fossils dating from the middle of the Eocene, it has significant geological and scientific importance. Over 1000 species of plants and animals have been found at the site. After almost becoming a landfill, strong local resistance eventually stopped these plans and the Messel pit was declared a UNESCO World Heritage Site on 9 December 1995. Significant scientific discoveries about the early evolution of mammals and birds are still being made at the Messel pit, and the site has increasingly become a tourist site as well.
Icaronycteris is an extinct genus of microchiropteran (echolocating) bat that lived in the early Eocene, approximately 52.2 million years ago, making it the earliest bat genus known from complete skeletons, and the earliest known bat from North America. Multiple exceptionally preserved specimens, among the best preserved bat fossils, are known from the Green River Formation of North America. The best known species is I. index. Fragmentary material from France has also been tentatively placed within Icaronycteris as the second species I. menui. I. sigei is based on well-preserved fragments of dentaries and lower teeth found in Western India. In 2023, the species I. gunnelli also from the Green River Formation was distinguished from I. index, and I. menui and I. sigei were proposed to be removed from the genus due to them not being closely related.
Palaeochiropteryx is an extinct genus of bat from the Middle Eocene of Europe and North America. It contains three very similar species – Palaeochiropteryx tupaiodon and Palaeochiropteryx spiegeli, both from the famous Messel Pit of Germany, as well as Palaeochiropteryx sambuceus from the Sheep Pass Formation. They are usually found complete and exceptionally preserved, even retaining the outlines of their fur, ears, and wing membranes.
Onychonycteris is the more primitive of the three oldest bats known from complete skeletons, having lived in the area that is current day Wyoming during the Eocene period, 52.5 million years ago.
Witwatia is an extinct genus of giant bat that contained two species which lived in the Al Fayyum in Egypt during the late Eocene and one species which lived in Tunisia during the early Eocene. It is known from a lower jaw and teeth. Three species have been named: the type species W. schlosseri, W. eremicus and W. sigei.
Archaeonycteris is an archaic bat genus whose fossilised remains have been found in Germany, France, England and India.
Antrozoini is a tribe of bats in the subfamily Vespertilioninae of the family Vespertilionidae. It contains the pallid bat, Van Gelder's bat, the genus Rhogeessa, and the fossil Anzanycteris. All species in this tribe are found in the Americas.
Archaeonycteridae is a family of extinct bats. It was originally erected by the Swiss naturalist Pierre Revilliod as Archaeonycterididae to hold the genus Archaeonycteris. It was formerly classified under the superfamily Icaronycteroidea (disused) by Kurten and Anderson in 1980. In 2007, the spelling was corrected to Archaeonycteridae and it was reclassified to the unranked clade Microchiropteramorpha by Smith et al.. The family Palaeochiropterygidae was also merged into Archaeonycteridae by Kurten and Anderson, but modern authorities specializing in bat fossils maintain the distinction between the two.
Philisidae is an extinct family of bats of the suborder Microchiroptera that lived between the Eocene to the Late Miocene in the continent of Africa.
Lesmesodon is an extinct genus of placental mammals from extinct family Proviverridae within extinct superfamily Hyaenodontoidea, that lived during the Early to Middle Eocene. It was found in France and in the Messel Pit in Germany. Lesmesodon was a weasel-sized carnivorous mammal.
Necromantis is an extinct genus of bat that lived during the Eocene. Its fossils are found in the Quercy Phosphorites Formation of France and the Djebel Chambi in Tunisia. Specimens of Necromantis are notable for their large size and specialization towards a predatory lifestyle.
Matthesia was a primitive bat genus in the family Palaeochiropterygidae. Matthesia is represented by two species known from the middle Lutetian of Geiseltal, Germany. It may be a junior synonym of Palaeochiropteryx.
Onychonycteridae is an extinct family of bats known only from the early Eocene of Europe and North America. The type species, Onychonycteris finneyi, was described in 2008 from two nearly complete skeletons found in the Green River Formation of southwestern Wyoming. Since that time a number of previously described fossil bat species have been assigned to Onychonycteridae, as well as two more recently discovered species.
Eocoracias is an extinct genus of bird related to modern rollers and other Coraciiformes such as kingfishers, bee-eaters, motmots, and todies. It contains one species, Eocoracias brachyptera, and it lived approximately 47 million years ago based on dating of the fossil site. It is known for a specimen having preserved non-iridescent structural coloration on its feathers, previously unknown in fossil birds. Fossils have been found at the Messel Pit in Germany.
Eoconstrictor is an extinct genus of booid snake, which supposedly had infrared vision, from the Eocene of Germany. The type species, E. fischeri is known from multiple well-preserved specimens found in the Messel Pit of Germany. It was originally named as Palaeopython fischeri by Stephan Schaal in 2004, but examination of the genus showed that it represented a distinct lineage; it was renamed as the new genus Eoconstrictor in 2020. In a subsequent study Georgalis, Rabi & Smith (2021) reinterpreted "Paleryx" spinifer from the Eocene Geiseltal Lagerstätte as the second species species belonging to the genus Eoconstrictor. Palci et al. (2023) named the third species belonging to this genus, E. barnesi described on the basis of fossils from the Geiseltal Lagerstätte.
Jens Lorenz Franzen was a German paleontologist. He was the head of Paleoanthropology and Quaternary at Naturmuseum Senckenberg in Frankfurt and participated in fossil excavation in Germany. He worked with scientific excavations and discovered many previously unknown fossil mammal species.
Hassianycteris is an extinct genus of Early Eocene (Ypresian) to Middle Eocene (Lutetian) bats from the Hassianycterididae with four or five known species: the type, H. magna, and H. revilliodi, all found in the Messel pit, Germany, H. kumari, found in the Cambay Shale Formation, India, and the possible fifth species "H." joeli, found in the Kortijk Clay Formation, Belgium, which may instead belong to Onychonycteridae. The Messel bats Palaeochiropteryx and Hassianycteris are the first fossil mammals whose colouration has been discovered: both were reddish-brown when alive.
This is an overview of the paleofauna of the Eocene Messel Formation as explored by the Messel Pit excavations in Germany. A former quarry and now UNESCO World Heritage Site, the Messel Formation preserves what once were a series of anoxic lakes surrounded by a sub-tropical rainforest during the Middle Eocene, approximately 47 Ma.
