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Bonnerichthys
''Bonnerichthys'' is a genus of fossil fishes within the family Pachycormidae that lived during the Late Cretaceous Period Fossil remains of this taxon were first described from the Smoky Hill Member of the Niobrara Chalk Formation of Kansas (Late Coniacian-Early Campanian, about 87-81 million years ago), and additional material was later reported from the Pierre Shale, Mooreville Chalk, Demopolis Chalk, Wenonah Formation, and Moreno Formation, among other localities. It grew to around 6 m (20 ft) in length, substantially less than the related ''Leedsichthys'' from the Jurassic which likely grew up to 17 m (56 ft). Feeding One of the most significant features of ''Bonnerichthys'' is the recognition that it was a filter feeder, living on plankton. This recognition that many large-bodied fish from the Mesozoic in the Pachycormidae were filter feeders shows that this niche was filled for at least 100 million years before previously known. The modern niche is filled by several s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachycormiformes
Pachycormiformes is an extinct order of marine ray-finned fish known from the Early Jurassic to the end of the Cretaceous. It only includes a single family, Pachycormidae. They were characterized by having serrated pectoral fins (though more recent studies demonstrated that fin shape diversity in this group was high), reduced pelvic fins and a bony rostrum. Their exact relations with other fish are unclear, but they are generally considered to be teleosteomorphs, more closely related to teleosts than to Holostei. Pachycormiformes are morphologically diverse, containing both tuna and swordfish-like carnivorous forms, as well as edentulous suspension-feeding forms, with the latter including the largest ray finned fish known to have existed, ''Leedsichthys,'' with an estimated maximum length of 16 metres. Synapomorphies Pachycormiformes are united by "a compound bone (rostrodermethmoid) forming the anterodorsal border of the mouth; a reduced coronoid process of the mandible; ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moreno Formation
The Moreno Formation is a Mesozoic geologic formation located in San Joaquin Valley (California).Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered from the formation.Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607. Paleofauna Ray-finned fish Dinosaurs Mosasaurs Plesiosaurs Turtles See also * List of dinosaur-bearing rock formations ** List of stratigraphic units with few dinosaur genera This list of stratigraphic units with few non-avian dinosaur genera includes Mesozoic stratigraphic units of formation rank or higher that have produced dinosaur body fossils which have been referred to at most five genera. Since taxonomy frequent ... Footnotes References * Hilton, Richard P. 2003. Dinosaurs and Other Mesozoic Reptiles of California. Berkeley: University of California Press. 318 pp. * Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachycormidae
Pachycormiformes is an extinct order of marine ray-finned fish known from the Early Jurassic to the end of the Cretaceous. It only includes a single family, Pachycormidae. They were characterized by having serrated pectoral fins (though more recent studies demonstrated that fin shape diversity in this group was high), reduced pelvic fins and a bony rostrum. Their exact relations with other fish are unclear, but they are generally considered to be teleosteomorphs, more closely related to teleosts than to Holostei. Pachycormiformes are morphologically diverse, containing both tuna and swordfish-like carnivorous forms, as well as edentulous suspension-feeding forms, with the latter including the largest ray finned fish known to have existed, ''Leedsichthys,'' with an estimated maximum length of 16 metres. Synapomorphies Pachycormiformes are united by "a compound bone (rostrodermethmoid) forming the anterodorsal border of the mouth; a reduced coronoid process of the mandible; ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leedsichthys
''Leedsichthys'' is an extinct genus of pachycormid fish that lived in the oceans of the Middle to Late Jurassic.Liston, JJ (2004). An overview of the pachycormiform ''Leedsichthys''. In: Arratia G and Tintori A (eds) Mesozoic Fishes 3 - Systematics, Paleoenvironments and Biodiversity. Verlag Dr. Friedrich Pfeil, München, pp 379–390. It is the largest ray-finned fish, and amongst the largest fish known to have ever existed. The first remains of ''Leedsichthys'' were identified in the nineteenth century. Especially important were the finds by the British collector Alfred Nicholson Leeds, after whom the genus was named "Leeds' fish" in 1889. The type species is ''Leedsichthys problematicus''. ''Leedsichthys'' fossils have been found in England, France, Germany and Chile. In 1999, based on the Chilean discoveries, a second species was named ''Leedsichthys notocetes'', but this was later shown to be indistinguishable from ''L. problematicus''. ''Leedsichthys'' fossils have been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Fish
The evolution of fish began about 530 million years ago during the Cambrian explosion. It was during this time that the early chordates developed the skull and the vertebral column, leading to the first craniates and vertebrates. The first fish lineages belong to the Agnatha, or jawless fish. Early examples include ''Haikouichthys''. During the late Cambrian, eel-like jawless fish called the conodonts, and small mostly armoured fish known as ostracoderms, first appeared. Most jawless fish are now extinct; but the extant lampreys may approximate ancient pre-jawed fish. Lampreys belong to the Cyclostomata, which includes the extant hagfish, and this group may have split early on from other agnathans. The earliest jawed vertebrates probably developed during the late Ordovician period. They are first represented in the fossil record from the Silurian by two groups of fish: the armoured fish known as placoderms, which evolved from the ostracoderms; and the Acanthodii (or spiny shark ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marion Charles Bonner
Marion Charles Bonner (1911–1992), based for most of his life in Leoti, Kansas, was an American field paleontologist who discovered and collected hundreds of fossils, primarily from the Niobrara Cretaceous Smoky Hill chalk outcroppings in Logan, Scott, and Gove counties of western Kansas. Largely self-taught, he frequently collaborated with museum paleontologists, including George F. Sternberg, at Fort Hays State University in Hays, Kansas, and Shelton P. Applegate, at the Los Angeles County Museum of Natural History. Notable fossils collected by Bonner Bonner’s fossil collecting career spanned 60 years. Notable specimens include a nearly complete short-necked plesiosaur, ''Dolichorhynchops'' ''osborni''; three new species of invertebrates -- ''Pecten'' ''bonneri'' (bivalve mollusk described in 1968), ''Niobrarateuthis bonneri'' (squid described in 1957), and ''Enchoteuthus melanae'' (squid described in 1968). A new fish genus occupying the bottom-feeding niche in the Niobrara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Taxa Described In 2010
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absolute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Ray-finned Fish Genera
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous Bony Fish
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baleen Whale
Baleen whales (systematic name Mysticeti), also known as whalebone whales, are a parvorder of carnivorous marine mammals of the infraorder Cetacea (whales, dolphins and porpoises) which use keratinaceous baleen plates (or "whalebone") in their mouths to sieve planktonic creatures from the water. Mysticeti comprises the families Balaenidae (right and bowhead whales), Balaenopteridae (rorquals and the gray whale), and Cetotheriidae (the pygmy right whale). There are currently 16 species of baleen whales. While cetaceans were historically thought to have descended from mesonychids, molecular evidence instead supports them as a clade of even-toed ungulates (Artiodactyla). Baleen whales split from toothed whales (Odontoceti) around 34 million years ago. Baleen whales range in size from the and pygmy right whale to the and blue whale, the largest known animal to have ever existed. They are sexually dimorphic. Baleen whales can have streamlined or large bodies, depending on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shark
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. However, the term "shark" has also been used to refer to all extinct members of Chondrichthyes with a shark-like morphology, such as hybodonts and xenacanths. The oldest modern sharks are known from the Early Jurassic. They range in size from the small dwarf lanternshark (''Etmopterus perryi''), a deep sea species that is only in length, to the whale shark (''Rhincodon typus''), the largest fish in the world, which reaches approximately in length. Sharks are found in all seas and are common to depths up to . They generally do not live in freshwater, although there are a few known exceptions, such as the bull shark and the river shark, which can be found in both seawater and fresh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Niche
In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for example, by growing when resources are abundant, and when predators, parasites and pathogens are scarce) and how it in turn alters those same factors (for example, limiting access to resources by other organisms, acting as a food source for predators and a consumer of prey). "The type and number of variables comprising the dimensions of an environmental niche vary from one species to another ndthe relative importance of particular environmental variables for a species may vary according to the geographic and biotic contexts". See also Chapter 2: Concepts of niches, pp. 7 ''ff'' A Grinnellian niche is determined by the habitat in which a species lives and its accompanying behavioral adaptations. An Eltonian niche emphasizes that a spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
