The Givetian is one of two faunal stages in the Middle Devonian Period. It lasted from 387.7 million years ago to 382.7 million years ago. It was preceded by the Eifelian Stage and followed by the Frasnian Stage. It is named after the town of Givet in France. The oldest forests occurred during the late Givetian. The lower GSSP is located at Jebel Mech Irdane, Tafilalt, Morocco.
Cheirolepis is an extinct genus of marine and freshwater ray-finned fish that lived in the Devonian period of Europe and North America. It is the only genus yet known within the family Cheirolepididae and the order Cheirolepidiformes. It was among the most basal of the Devonian actinopterygians and is considered the first to possess the "standard" dermal cranial bones seen in later actinopterygians.
Rhenanida is an order of scaly placoderms. Unlike most other placoderms, the rhenanids' armor was made up of a mosaic of unfused scales and tubercles. The patterns and components of this "mosaic" correspond to the plates of armor in other, more advanced placoderms, suggesting that the ancestral placoderm had armor made of unfused components, as well.
The Eifelian is the first of two faunal stages in the Middle Devonian Epoch. It lasted from 393.3 ± 1.2 million years ago to 387.7 ± 0.8 million years ago. It was preceded by the Emsian Stage and followed by the Givetian Stage.
Chotecops is a genus of trilobites from the order Phacopida, suborder Phacopina, family Phacopidae. It was initially erected as a subgenus of Phacops but some later authors thought it distinctive enough to raise its status. Species assigned to this genus occur between the Emsian and the Famennian. Chotecops is the most abundant trilobite in the Hunsrück Slate and due to the excellent preservation, often soft tissue such as antennae and legs have been preserved as a thin sheet of pyrite.
Eldredgeops is a genus of trilobites in the order Phacopida, family Phacopidae, known from the late Middle and earliest Upper Devonian of Morocco and the USA.
The Kačák Event, also known as the Kačák-otomari Event, is a widely recognised bioevent or series of events that occurred close to the end of the Eifelian Age of the Middle Devonian Epoch. It involved a global eustatic rise in sea level and ecological turnover. It was named for the Kačák Member of the Srbsko Formation in Bohemia, where it is represented by a black shale interval within a sequence of limestone. In marine environments, this appears as an anoxic event, often forming potential hydrocarbon source rocks such as the Marcellus Shale. Within the Old Red Sandstone continent, it is represented by the Achanarras lake, the deepest and most widespread lake that developed within the Orcadian Basin. The event is associated with significant extinctions, particularly amongst the Ammonoidea.
Luckeus is an extinct genus of prehistoric lobe-finned fish. Luckeus belonged to the order Onychodontida. It lived during the Early Devonian to Middle Devonian period in what os now central Australia.
Homosteus is a genus of flattened arthrodire placoderm from the Middle Devonian. Fossils are found primarily in Eifelian-epoch aged strata of Europe, Canada, Greenland, and Estonia. All of the species had comparatively large, flattened heads with, as suggested by the upward opening orbits, upward-pointing eyes. These adaptations suggest that the various species were benthic predators. A study on Titanichthys, in contrast, suggests that species of Homosteus may have been filter-feeders instead.
Holonema is an extinct genus of relatively large, barrel-shaped arthrodire placoderms that were found in oceans throughout the world from the Mid to Late Devonian, when the last species perished in the Frasnian-Fammian extinction event. Most species of the genus are known from fragments of their armor, but the Gogo Reef species, H. westolli, is known from whole, articulated specimens.
Glyptolepis is an extinct genus of porolepiform lobe-finned fish which lived during Devonian Period, from the early Eifelian to Frasnian Age. Species include Glyptolepis baltica and Glypotlepis leptopterus.
Deinodus is a form genus that includes two species: the form found in the Onondaga Formation of western New York, Deinodus bennetti, and the form found in the Columbus and Limestone of central Ohio, Deinodus ohioensis. Both species are limited to the Eifelian age of the middle Devonian Period, which occurred 398-391 million years ago.
Favosites is an extinct genus of tabulate coral characterized by polygonal closely packed corallites. The walls between corallites are pierced by pores known as mural pores which allowed transfer of nutrients between polyps. Favosites, like many corals, thrived in warm sunlit seas, feeding by filtering microscopic plankton with their stinging tentacles and often forming part of reef complexes. The genus had a worldwide distribution from the Late Ordovician to Late Permian.
Protitanichthys is an extinct genus of comparatively large coccosteid arthrodire placoderms from the Middle Devonian of the eastern United States. Fossils are found primarily in the Eifelian-epoch aged Delaware Limestone of Ohio, and the Lower Givetian-aged Rockport Quarry Limestone of Michigan
Macropetalichthys is a genus of placoderm fish, named by Norwood and Owen in 1846; the name "Macropetalichthys" means "armor-plated fish". It was assigned to Arthrodira by Woodward (1891); and to Petalichthida by Sepkoski (2002). Several species have been referred to Macropetalichthyes, but the best known is the type species, M. rapheidolabis, from the Jeffersonville Limestone of Indiana, USA, and Columbus Limestone of Ohio, USA.
Paraspirifer is a genus of large brachiopods that lived during the late Lower and Middle Devonian in what now are Germany, Spain, Morocco and the United States.
Chamaeleoaspis is a genus of tiny trilobites found in Early to Middle Eifelian marine strata of Africa and Europe. The two species look very similar to the trilobites of the related genera Cyphaspis and Otarionella, in which the species were originally, successively classified in. Fossils of the older species, C. lkomalii, are found in a locality at the southern end of the Maider Basin, in the Anti-Atlas Mountains. Fossils of the type species, C. chamaeleo, are found in the Middle Eifelian-aged Ohle Formation in Endorf, Germany..
Icriodus is an extinct conodont genus in the family Gnathodontidae.
Herasmius is an extinct genus of heterosteid placoderm from the Devonian period. Fossils have been discovered freshwater deposits in Norway and Canada.
The Vireux-Molhain national nature reserve (RNN104) is a national nature reserve of geological and paleontological interest. It is located in the Pointe de Givet, department of Ardennes, on the border between France and Belgium. It covers an area of 1.82 ha. The site is known as Customs Wall as it is near an old customs post. This outcrop of Middle Devonian shale is notable for the quantity and good state of preservation of its fossils. Trilobites are well-represented.
