| Hemicidaridae Temporal range: | |
|---|---|
 | |
| Fossil of Asterocidaris species | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Echinodermata |
| Class: | Echinoidea |
| Infraclass: | Carinacea |
| Family: | † Hemicidaridae Wright, 1857 |
Hemicidaridae is a family of extinct sea urchins characterized by large, massive, club-shaped spines.
These epifaunal grazer-deposit feeders lived in Jurassic and Cretaceous ages (from 189.6 to 112.6 Ma). [1]
List of genera and subfamilies: [2] [3]
Fossils of species within this genus have been found in the Jurassic and Cretaceous sediments in Europe, Africa, North America and China. [1]
The Amiiformes order of fish has only two extant species, the bowfins: Amia calva and Amia ocellicauda, the latter recognized as a separate species in 2022. These Amiiformes are found in the freshwater systems of North America, in the United States and parts of southern Canada. They live in freshwater streams, rivers, and swamps. The order first appeared in the Triassic, and the extinct members include both marine and freshwater species, many of which are morphologically disparate from bowfins, such as the caturids.
The Amiidae are a family of basal ray-finned fishes. The bowfin and the eyespot bowfin are the only two species to survive today, although additional species in all four subfamilies of Amiidae are known from Jurassic, Cretaceous, and Eocene fossils.
The Lamniformes are an order of sharks commonly known as mackerel sharks. It includes some of the most familiar species of sharks, such as the great white, as well as more unusual representatives, such as the goblin shark and megamouth shark.
Caturus is an extinct genus of predatory marine fishes in the family Caturidae in the order Amiiformes, related to modern bowfin. It has been suggested that the genus is non-monophyletic with respect to other caturid genera.
Lepidotes is an extinct genus of Mesozoic ray-finned fish. It has long been considered a wastebasket taxon, characterised by "general features, such as thick rhomboid scales and, for most of the species, by semi-tritorial or strongly tritorial dentition". with dozens of species assigned to it. Fossils attributed to Lepidotes have been found in Jurassic and Cretaceous rocks worldwide. It has been argued that Lepidotes should be restricted to species closely related to the type species L. gigas, which are only known from the Early Jurassic of Western and Central Europe, with most other species being not closely related, with other species transferred to new genera such as Scheenstia.Lepidotes belongs to Ginglymodi, a clade of fish whose only living representatives are the gars (Lepisosteidae). The type species L. gigas and close relatives are thought to be members of the family Lepidotidae, part of the order Lepisosteiformes within Ginglymodi, with other species occupying various other positions within Ginglymodi.
Berriasella is a discoidal evolute perisphinctacean ammonite, and type genus for the neocomitid subfamily Berriasellinae. Its ribbing is distinct, consisting of both simple and bifurcated ribs that extend from the umbilical seam across the venter; its whorl section generally compressed, the venter more or less narrowly rounded. The species Berriasella jacobi traditionally has been regarded an index fossil defining the base of the Cretaceous, however since 2016 this had been replaced by the first occurrence of Calpionella alpina. Some authors regard B. jacobi as instead belonging to the genus Strambergella.
Ceratodus is an extinct genus of lungfish. It has been described as a "catch all", and a "form genus" used to refer to the remains of a variety of lungfish belonging to the extinct family Ceratodontidae. Fossil evidence dates back to the Early Triassic. A wide range of fossil species from different time periods have been found around the world in places such as the United States, Argentina, Greenland, England, Germany, Egypt, Madagascar, China, and Australia. Ceratodus is believed to have become extinct sometime around the beginning of the Eocene Epoch.
Carcharias is a genus of mackerel sharks belonging to the family Odontaspididae. Once bearing many prehistoric species, all have gone extinct with the exception of the critically endangered sand tiger shark.
Goniasteridae constitute the largest family of sea stars, included in the order Valvatida. They are mostly deep-dwelling species, but the family also include several colorful shallow tropical species.
Belonostomus is a genus of prehistoric ray-finned fish that was described by Louis Agassiz in 1844. It is a member of the order Aspidorhynchiformes, a group of fish known for their distinctive elongated rostrums.
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.
Vinctifer is an extinct genus of prehistoric bony fish erected by David Starr Jordan in 1919.
Ptychoceratodus is an extinct genus of lungfish living from Early Triassic to Middle Jurassic. It was established by Otto Jaekel for one species, transferred from Ceratodus genus. Type species is P. serratus from the Middle Triassic of Switzerland and Germany. Ptychoceratodus had two pairs of massive dental plates, bearing 4-6 acute ridges. Its skull roof was composed from massive, plate-like bones. In the central part of skull roof was localized an unossified fenestra. Most of the Ptychoceratodus findings are isolated dental plates, some associated with jaws. Other parts of skull or postcranial skeleton are relatively rarely found as fossils. The anatomy of skull is the best recognized in P. serratus, whereas less complete cranial material is available also for P. concinuus, P. phillipsi, and P. rectangulus. Although Ptychoceratodus is known exclusively from the Triassic and Jurassic, there were also Cretaceous specimens referred to this genus. However, they are more often regarded as representants of Metaceratodus. Ptychoceratodus is the only member of the family Ptychoceratodontidae. The first named species is P. phillipsi by Louis Agassiz in 1837 as a species of Ceratodus and later moved to Ptychoceratodus genus. Occurrences of Ptychoceratodus come mainly from Europe. However, occurrences from other continents suggest it was dispersed globally during the Triassic. After 2010, the new fossil material behind the Europe was reported from South America, India, and Greenland
Callipurbeckia is an extinct genus of marine semionotiform ray-finned fish from the Late Jurassic and Early Cretaceous periods. Fossils have been found in Germany, Tanzania, and England.
Diplocidaris is an extinct genus of sea urchins belonging to the family Diplocidaridae. The type species of this genus is Cidaris gigantea Agassiz, 1840.
Asterocidaris is a genus of fossils sea urchins in the family Hemicidaridae. These epifaunal grazer-deposit feeders lived in the Middle and Upper Jurassic age.
Serratolamna is an extinct genus of mackerel sharks that is placed in the monotypic family Serratolamnidae.
Tetragramma is a genus of fossil sea urchins known from the Upper Jurassic (Oxfordian) to the Upper Cretaceous (Turonian).
Strophodus is an extinct genus of durophagous hybodont known from the Triassic to Cretaceous. It was formerly confused with Asteracanthus.
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