|
Gebrayelichthyidae
Gebrayelichthyidae is a family of extinct pycnodontid fish, with a superficially shrimpfish-like appearance that lived during the lower Cenomanian. The family is composed of two genera, the type genus, '' Gebrayelichthys'', and the monotypic '' Maraldichthys''. The Gebrayelichthyids are highly modified in appearance, having their bodies compressed and vertebrae elongated. Gebrayelichthyidae, together with Gladiopycnodontidae and Coccodontidae, make up the pycnodontid superfamily Coccodontoidea. Description ''Gebrayelichthys'' was strongly flattened on the sides. The body height was 1.8 to 2 times the body length. The head and torso each made up half of the total length. The skull was similar to that of other Pycnodontiformes. The orbit was high up under the curved head profile, the muzzle was long and directed downwards. There were a few pointed teeth on the ploughshare. The anatomy of the lower jaw is unknown due to the lack of evidence. Behind the skull was a tall bone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pycnodontiformes
Pycnodontiformes is an extinct order of primarily marine bony fish. The group first appeared during the Late Triassic and disappeared during the Eocene. The group has been found in rock formations in Africa, Asia, Europe, North and South America. They were small to middle-sized fish, generally with laterally-compressed deep bodies, some with almost circular outlines, adapted for manuverability in reef-like environments. The group was morphologically diverse containing forms such the very short but deep Gebrayelichthyidae and the horned ''Ichthyoceros,'' both from the early Late Cretaceous of Lebanon. Most, but not all members of the groups had jaws with round and flattened teeth, well adapted to crush food items (durophagy), such as echinoderms, crustaceans and molluscs. Some pyncodontiformes developed piranha like teeth used for eating flesh. Most species inhabited shallow marine reef environments, while a handful of species lived in freshwater or brackish conditions. While rare ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccodontidae
Coccodontidae is a family of extinct pycnodontid fish that lived during the lower Cenomanian. The various genera had massive, curved spines. The family is composed of five genera, the type genus, ''Coccodus'', '' Paracoccodus'' which was split off from ''Coccodus'', the newly described ''Corusichthys'', the sexually dimorphic ''Hensodon'', and ''Trewavasia''. ''Ichthyoceros'' was, at one time, placed in Coccodontidae, but then was moved with ''Trewavasia'' in "Trewavasiidae,"Nursall, Ralph Mesozoic Fishes – Systematics and Paleoecology, G. Arratia & G. Viohl (eds.), Verlag Dr. Friedrich Pfeil, München, Germany, 1996 – "The phylogeny of pycnodont fishes" and then, in 2014, was placed in the related pycnodontid family Gladiopycnodontidae, while ''Trewavasia'' was returned to Coccodontidae. Coccodontidae, together with Gladiopycnodontidae and the superficially shrimpfish-like Gebrayelichthyidae, make up the pycnodontid superfamily Coccodontoidea. See also * Prehistoric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenomanian
The Cenomanian is, in the ICS' geological timescale, the oldest or earliest age of the Late Cretaceous Epoch or the lowest stage of the Upper Cretaceous Series. An age is a unit of geochronology; it is a unit of time; the stage is a unit in the stratigraphic column deposited during the corresponding age. Both age and stage bear the same name. As a unit of geologic time measure, the Cenomanian Age spans the time between 100.5 and 93.9 million years ago (Mya). In the geologic timescale, it is preceded by the Albian and is followed by the Turonian. The Upper Cenomanian starts around at 95 Mya. The Cenomanian is coeval with the Woodbinian of the regional timescale of the Gulf of Mexico and the early part of the Eaglefordian of the regional timescale of the East Coast of the United States. At the end of the Cenomanian, an anoxic event took place, called the Cenomanian-Turonian boundary event or the "Bonarelli event", that is associated with a minor extinction event for marine spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type Genus
In biological taxonomy, the type genus is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearing type of a nominal family-group taxon is a nominal genus called the 'type genus'; the family-group name is based upon that of the type genus." Any family-group name must have a type genus (and any genus-group name must have a type species, but any species-group name may, but need not, have one or more type specimens). The type genus for a family-group name is also the genus that provided the stem to which was added the ending -idae (for families). :Example: The family name Formicidae has as its type genus the genus ''Formica'' Linnaeus, 1758. Botanical nomenclature In botanical nomenclature, the phrase "type genus" is used, unofficially, as a term of convenience. In the '' ICN'' this phrase has no status. The code uses type specimens for ranks up to fam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Ray-finned Fish Families
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. ... [...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] |
Late Cretaceous Fish
Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, a concept in econometrics Music * ''Late'' (album), a 2000 album by The 77s * Late!, a pseudonym used by Dave Grohl on his ''Pocketwatch'' album * Late (rapper), an underground rapper from Wolverhampton * "Late" (song), a song by Blue Angel * "Late", a song by Kanye West from ''Late Registration'' Other * Late (Tonga), an uninhabited volcanic island southwest of Vavau in the kingdom of Tonga * "Late" (''The Handmaid's Tale''), a television episode * LaTe, Oy Laivateollisuus Ab, a defunct shipbuilding company * Late may refer to a person who is Dead See also * * * ''Lates'', a genus of fish in the lates perch family * Later (other) * Tardiness * Tardiness (scheduling) In scheduling, tardiness is a measure of a delay in exe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Notochord
In anatomy, the notochord is a flexible rod which is similar in structure to the stiffer cartilage. If a species has a notochord at any stage of its life cycle (along with 4 other features), it is, by definition, a chordate. The notochord consists of inner, vacuolated cells covered by fibrous and elastic sheaths, lies along the anteroposterior axis (''front to back''), is usually closer to the dorsal than the ventral surface of the embryo, and is composed of cells derived from the mesoderm. The most commonly cited functions of the notochord are: as a midline tissue that provides directional signals to surrounding tissue during development, as a skeletal (structural) element, and as a vertebral precursor. In lancelets the notochord persists throughout life as the main structural support of the body. In tunicates the notochord is present only in the larval stage, being completely absent in the adult animal. In these invertebrate chordates, the notochord is not vacuolated. In all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic Taxon
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. In contrast, an oligotypic taxon contains more than one but only a very few subordinate taxa. Examples Just as the term ''monotypic'' is used to describe a taxon including only one subdivision, the contained taxon can also be referred to as monotypic within the higher-level taxon, e.g. a genus monotypic within a family. Some examples of monotypic groups are: Plants * In the order Amborellales, there is only one family, Amborellaceae and there is only one genus, '' Amborella'', and in this genus there is only one species, namely ''Amborella trichopoda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shrimpfish
Shrimpfish, also called razorfish, are five small species of marine fishes in the subfamily Centriscinae of the family Centriscidae. The species in the genera ''Aeoliscus'' and ''Centriscus'' are found in relatively shallow tropical parts of the Indo-Pacific, while the banded bellowsfish, which often is placed in the subfamily Macroramphosinae instead, is restricted to deeper southern oceans. Shrimpfish are nearly transparent and flattened from side to side with long snouts and sharp-edged bellies. A thin, dark stripe runs along their bodies. These stripes and their shrimp Shrimp are crustaceans (a form of shellfish) with elongated bodies and a primarily swimming mode of locomotion – most commonly Caridea and Dendrobranchiata of the decapod order, although some crustaceans outside of this order are refer ...-like appearance are the source of their name. They swim in a synchronized manner with their heads pointing downwards. Adult shrimpfish are up to long, includin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
