Obdurodon is a genus of extinct platypus-like Australian monotreme which lived from the Late Oligocene to the Late Miocene. Three species have been described in the genus, the type species Obdurodon insignis, plus Obdurodon dicksoni and Obdurodon tharalkooschild. The species appeared much like their modern day relative the platypus, except adults retained their molar teeth, and unlike the platypus, which forages on the lakebed, they may have foraged in the water column or surface.
Podocnemididae is a family of pleurodire (side-necked) turtles, once widely distributed. Most of its 41 genera and 57 species are now extinct. Seven of its eight surviving species are native to South America: the genus Peltocephalus, with two species, only one of which is extant ; and the genus Podocnemis, with six living species of South American side-necked river turtles and four extinct. There is also one genus native to Madagascar: Erymnochelys, the Madagascan big-headed turtle, whose single species E. madagascariensis.
The three-spined stickleback is a fish native to most inland and coastal waters north of 30°N. It has long been a subject of scientific study for many reasons. It shows great morphological variation throughout its range, ideal for questions about evolution and population genetics. Many populations are anadromous and very tolerant of changes in salinity, a subject of interest to physiologists. It displays elaborate breeding behavior and it can be social making it a popular subject of inquiry in fish ethology and behavioral ecology. Its antipredator adaptations, host-parasite interactions, sensory physiology, reproductive physiology, and endocrinology have also been much studied. Facilitating these studies is the fact that the three-spined stickleback is easy to find in nature and easy to keep in aquaria.
Platygonus is an extinct genus of herbivorous peccaries of the family Tayassuidae, endemic to North and South America from the Miocene through Pleistocene epochs, existing for about 10.289 million years. P. compressus stood 2.5 feet tall.
Diplomystus is an extinct genus of freshwater and marine clupeomorph fish distantly related to modern-day extant herrings, anchovies, and sardines. It is known from the United States, China, and Lebanon from the Late Cretaceous to the middle Eocene. Many other clupeomorph species from around the world were also formerly placed in the genus, due to it being a former wastebasket taxon. It was among the last surviving members of the formerly-diverse order Ellimmichthyiformes, with only its close relative Guiclupea living for longer.
La Venta is a fossil locality located in the modern departments of Tolima and Huila in Colombia. This site is one of the richest Neogene fossil assemblages in South America and represents the best-known Cenozoic fossil site outside of Argentina. It provides a glimpse of what life in the region was like before the main wave of the Great American Interchange.
Litokoala is an extinct genus of marsupials, and along with Nimiokoala, is closely related to the modern koala. The three genera may have diverged at an earlier date, although the drying of the continent and the expansion of Eucalyptus forests towards the late Miocene may have delayed the evolution of cranial features unique to the modern genera. This indicates that either fossil genus could be an ancestor of the modern genus, or the modern genus has a common ancestor to both. More material needs collection to improve their taxonomical relationships.
Gasterosteus is a genus of ray-finned fishes belonging to the family Gasterosteidae, the sticklebacks. These fishes are found in freshwater, brackish water and marine habitats in the Holarctic region.
A planktivore is an aquatic organism that feeds on planktonic food, including zooplankton and phytoplankton. Planktivorous organisms encompass a range of some of the planet's smallest to largest multicellular animals in both the present day and in the past billion years; basking sharks and copepods are just two examples of giant and microscopic organisms that feed upon plankton.
In biogeography and paleontology, a relict is a population or taxon of organisms that was more widespread or more diverse in the past. A relictual population is a population currently inhabiting a restricted area whose range was far wider during a previous geologic epoch. Similarly, a relictual taxon is a taxon which is the sole surviving representative of a formerly diverse group.
Aphaenogaster avita is an extinct species of ant in the subfamily Myrmicinae known from a solitary early to middle Miocene fossil found in Japan. At the time of description A. praerelicta was one of twelve Aphaenogaster species to have been described from fossils and the only fossil species from Japan.
The Truckee Formation is a lacustrine geologic formation in Nevada, USA. It preserves fossils dating back to the late Miocene. Part of the Lahontan Basin, it was deposited in the prehistoric Lake Truckee, a predecessor to Lake Lahontan.
This list of fossil fish research presented in 2021 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes, and other fishes that were described during the year, as well as other significant discoveries and events related to paleoichthyology that occurred in 2021.
The Ngorora Formation is a geological formation in Kenya preserving fossils dating to the Miocene. The uppermost member of the formation shows sign of a faunal turnover that occurred around 11 to 10.5 million years ago, coinciding with faunal changes elsewhere in the world. This turnover includes the arrival of the horse Hipparion in East Africa. The Ngorora Formation was initially mapped by G.R. Chapman in collaboration with the East African Geological Research Unit (EAGRU) and formally described by Bishop & Chapman in 1970. Major fossil finds were made in the early 1970s, with expeditions to the area recovering thousands of mammal, fish and mollusc remains alongside less common fossil material of birds and reptiles.
Megadolodus is an extinct genus of proterotheriid litopterns.
Pseudoprepotherium is an extinct genus of sloths of the family Mylodontidae. It was widespread across northern South America during the Early to Late Miocene epoch around 21 to 5.3 million years ago. Fossils of the animal have been found in Brazil, Venezuela, and Peru. Pseudoprepotherium lived in a tropical climate with a water-rich environment. Their known remains are limited to limb bones, except for a few skulls and teeth. Based on these remains, they were most likely medium to large-sized mylodontid. The genus was described in 1961 and currently contains three species, which were originally assigned to the genus Prepotherium.
Caiman australis is an extinct species of caiman described in 1858 on the basis of a left maxilla that was collected from the Upper Miocene age Ituzaingó Formation of Entre Rios, Argentina.
Asilifelis is an extinct genus of small felid that lived in what is now Kenya during the Early Miocene. Despite its fragmentary remains, it is remarkable because of its small size and advanced dentition. It contains a single species, Asilifelis cotae.
Miodytes is a fossil genus of grebe known from a nearly complete specimen from Valjevo Basin, western Serbia known from an almost complete right wing skeleton. It contains a single species, M. serbicus.
