| Dagonodum | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Infraorder: | Cetacea |
| Family: | Ziphiidae |
| Genus: | † Dagonodum Ramassamy, 2016 |
| Species: | †D. mojnum |
| Binomial name | |
| †Dagonodum mojnum Ramassamy, 2016 | |
Dagonodum is an extinct genus of ziphiid cetacean known from Tortonian age marine deposits in the Gram Formation in Denmark. There is only one known species, Dagonodum mojnum. [1]
The genus name is a reference to the god Dagon, worshiped as the head god and as a deity of prosperity in ancient inland Syria, but best known from H.P. Lovecraft's short story, where he is instead depicted as deep-sea deity. The species name is a reference to the word for "goodbye" in the local South Jutlandic dialect where the fossils were found. The word, "mojn", is of German origin, where it is used as both a greeting and a farewell. [1]
The species is distinguished by its two pairs of mandibular tusks and long snout. It also possessed a long neck, leading to speculation that it wasn't well suited to deep-dives. [1]
The species is notable for its difference from other ziphiidae of the period in that it seems to be less reliant on suction feeding. [2]
The earless seals, phocids or true seals are one of the three main groups of mammals within the seal lineage, Pinnipedia. All true seals are members of the family Phocidae. They are sometimes called crawling seals to distinguish them from the fur seals and sea lions of the family Otariidae. Seals live in the oceans of both hemispheres and, with the exception of the more tropical monk seals, are mostly confined to polar, subpolar, and temperate climates. The Baikal seal is the only species of exclusively freshwater seal.
Beaked whales are a family of cetaceans noted as being one of the least known groups of mammals because of their deep-sea habitat, reclusive behavior and apparent low abundance. Only three or four of the 24 existing species are reasonably well-known. Baird's beaked whales and Cuvier's beaked whales were subject to commercial exploitation, off the coast of Japan, while the northern bottlenose whale was extensively hunted in the northern part of the North Atlantic in the late 19th and early 20th centuries.
Kogiidae is a family comprising at least two extant species of Cetacea, the pygmy and dwarf sperm whales. As their common names suggest, they somewhat resemble sperm whales, with squared heads and small lower jaws, but are much smaller in size, with much shorter skulls and more notable dorsal fins than sperm whales. Kogiids are also characterized by a "false gill slit" behind their eyes.
Mesoplodont whales are 16 species of toothed whale in the genus Mesoplodon, making it the largest genus in the cetacean order. Two species were described as recently as 1991 and 2002, and marine biologists predict the discovery of more species in the future. A new species was described in 2021. They are the most poorly known group of large mammals. The generic name "mesoplodon" comes from the Greek meso- (middle) - hopla (arms) - odon (teeth), and may be translated as 'armed with a tooth in the centre of the jaw'.
Hector's beaked whale, is a small mesoplodont living in the Southern Hemisphere. This whale is named after Sir James Hector, a founder of the colonial museum in Wellington, New Zealand. The species has rarely been seen in the wild.
The Cuvier's beaked whale, goose-beaked whale, or ziphius is the most widely distributed of all beaked whales in the family Ziphiidae. It is smaller than most baleen whales yet large among beaked whales. Cuvier's beaked whale is pelagic, inhabiting waters deeper than 300 m (1,000 ft). It has the deepest and longest recorded dives among whales at 2,992 m (9,816 ft) and 222 minutes, though the frequency and reasons for these extraordinary dives are unclear. Despite its deep-water habitat, it is one of the most frequently spotted beached whales.
The four-toothed whales or giant beaked whales are beaked whales in the genus Berardius. They include Arnoux's beaked whale in cold Southern Hemispheric waters, and Baird's beaked whale in the cold temperate waters of the North Pacific. A third species, Sato's beaked whale, was distinguished from B. bairdii in the 2010s.
The dwarf sperm whale is a sperm whale that inhabits temperate and tropical oceans worldwide, in particular continental shelves and slopes. It was first described by biologist Richard Owen in 1866, based on illustrations by naturalist Sir Walter Elliot. The species was considered to be synonymous with the pygmy sperm whale from 1878 until 1998. The dwarf sperm whale is a small whale, 2 to 2.7 m and 136 to 272 kg, that has a grey coloration, square head, small jaw, and robust body. Its appearance is very similar to the pygmy sperm whale, distinguished mainly by the position of the dorsal fin on the body–nearer the middle in the dwarf sperm whale and nearer the tail in the other.
Perrin's beaked whale is part of the toothed whale suborder and is one of over 90 known cetaceans in existence today. Beaked whales are part of the family Ziphiidae, which are the second most diverse group out of all marine mammals with over 20 species currently recognized. Although diverse, little is understood about these timid, deep divers that can dive for up to two hours. The whales are partially named after their beak shaped jaw, which extends from their small head. The genus name Mesoplodon comes from the Greek meanings of meso- (middle), - hopla (arms), - odon (teeth), and may be translated as 'armed with a tooth in the center of the jaw'.
The horn shark is a species of bullhead shark, in the family Heterodontidae. It is endemic to the coastal waters off the western coast of North America, from California to the Gulf of California. Young sharks are segregated spatially from the adults, with the former preferring deeper sandy flats and the latter preferring shallower rocky reefs or algal beds. A small species typically measuring 1 m (3.3 ft) in length, the horn shark can be recognized by a short, blunt head with ridges over its eyes, two high dorsal fins with large spines, and a brown or gray coloration with many small dark spots.
The Pleurodira are one of the two living suborders of turtles, the other being the Cryptodira. The division between these two suborders represents a very deep evolutionary divide between two very different types of turtles. The physical differences between them, although anatomical and largely internal, are nonetheless significant, and the zoogeographic implications of them are substantial. The Pleurodira are known more commonly as the side-necked turtles and the name Pleurodira quite literally translates to side neck, whereas the Cryptodira are known as hidden-necked turtles. The Pleurodira turtles are currently restricted to freshwater habitats in the Southern Hemisphere, largely to Australia, South America, and Africa. Within the Pleurodira, three living families are represented: Chelidae, also known as the Austro-South American side-necked turtles, the Pelomedusidae, also known as the African mud terrapins, and the Podocnemididae, also known as the American side-neck river turtles. However, they were cosmopolitan clade during the Cretaceous and most of the Cenozoic, and even occurred in marine environments around the world.
Shastasaurus is an extinct genus of very large ichthyosaur from the middle and late Triassic, and is the largest known marine reptile. Specimens have been found in the United States, Canada, and China.
Australodelphis mirus is an extinct Pliocene dolphin. A. mirus is known from fossils found in the Sørsdal Formation, Mule Peninsula, Vestfold Hills, East Antarctica. The genus has been described as an example of convergent evolution with beaked whales.
Sokatra is an extinct genus of pleurodiran turtle, known from the Cretaceous (Maastrichtian) Maevarano Formation of Madagascar. It belongs to the family Sahonachelyidae.
Araripemydidae is a family of freshwater aquatic turtles belonging to the order Pleurodira, known from the Early Cretaceous of South America and Africa. The family contains two recognised monotypic genera, Araripemys and Taquetochelys, from the Santana Group of Brazil and the Elrhaz Formation of Niger, respectively, which date to the Aptian-Albian stages of the Early Cretaceous. They are consider to be the most basal lineage within the Pelomedusoides. They are thought to have been specialised suction feeders. Laganemys was named in 2013 but was later determined to be synonymous with Taquetochelys.
Mystacodon is a genus of toothed baleen whale from the Late Eocene Yumaque Formation of the Pisco Basin in southwestern Peru. It is the oldest known baleen whale, and was probably a suction feeder of small prey on the seafloor.
Gram Natural History Museum opened in 1976 in Gram in the Southern Jutland area of Denmark. It was located in Gram Palace until it was moved to a site next to the Gram Clay Pit in 2005. Once an independent museum, it became a part of the larger constellation of museums in Southern Jutland known as Museum Sønderjylland.
The Gram Formation is a geological formation in Gram, Denmark. It preserves fossils dating from the Miocene period. The formation consists of three layers: the glauconite-rich, the Gram Clay, and the Gram sand. The sediments in the formation were deposited in an open marine depositional environment known as the Gram Sea.
Sahonachelys is an extinct genus of pelomedusoid turtle from the Late Cretaceous (Maastrichtian) Maevarano Formation of Madagascar. The genus contains a single species, Sahonachelys mailakavava.
Shashajaia is a genus of extinct non-mammalian synapsids from the late Carboniferous to Early Permian. It was one of the earliest members of the group, coming from the Gzhelian stage. It lived in what is now the Halgaito Formation within the larger Cutler group located in the U.S state of Utah. According to a description study, this synapsid is known from well preserved dentary and jaw fragments. Shashajaia shares many similarities to other sphenacodontids including, enlarged (canine-like) anterior dentary teeth, a dorsoventrally deep symphysis and low-crowned, subthecodont postcanines having festooned plicidentine. The study also found that this genus is close to the evolutionary divergence of the Sphenacodontids and the Therapsids, from which mammalian synapsids arose from. Based on studies done on its teeth, Paleontologists found that as their prey became more terrestrial, synapsids like Shashajaia adapted to life on land and grew larger teeth to deal with larger herbivores in a evolutionary arms race.
