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Microtherulum
''Microtherulum'' is an extinct genus of eutherian mammal known from the Early Cretaceous Jiufotang Formation of China. It is one of the earliest and most primitive eutherians. Description The genus is known from a mostly complete skeleton, including a well preserved skull, which is about long. The ear, which is among the best known in basal eutherians, is microtype, adapted for hearing high-frequency sounds. The dental formula is 5 incisors, 1 canine, 5 premolars and 3 molars The molars or molar teeth are large, flat tooth, teeth at the back of the mouth. They are more developed in mammal, mammals. They are used primarily to comminution, grind food during mastication, chewing. The name ''molar'' derives from Latin, '' ... in the each half of the upper jaw, and 4 incisors, 1 canine, 5 premolars and 3 molars in each half of the lower jaw, which is typical for basal eutherians. Phylogeny ''Microtherulum'' has been placed close to the base of Eutheria. References {{Taxonbar, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutherian
Eutheria (from Greek , 'good, right' and , 'beast'; ), also called Pan-Placentalia, is the clade consisting of placental mammals and all therian mammals that are more closely related to placentals than to marsupials. Eutherians are distinguished from non-eutherians by various phenotypic traits of the feet, ankles, jaws and teeth. All extant eutherians lack epipubic bones, which are present in all other living mammals (marsupials and monotremes). This allows for expansion of the abdomen during pregnancy, though epipubic bones are present in many primitive eutherians. Eutheria was named in 1872 by Theodore Gill; in 1880, Thomas Henry Huxley defined it to encompass a more broadly defined group than Placentalia. The earliest unambiguous eutherians are known from the Early Cretaceous Yixian Formation of China, dating around 120 million years ago. Two tribosphenic mammals, '' Durlstodon'' and '' Durlstotherium'' from the Berriasian age (~145–140 million years ago) of the Ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutheria
Eutheria (from Greek , 'good, right' and , 'beast'; ), also called Pan-Placentalia, is the clade consisting of Placentalia, placental mammals and all therian mammals that are more closely related to placentals than to marsupials. Eutherians are distinguished from non-eutherians by various phenotypic traits of the feet, ankles, jaws and teeth. All extant eutherians lack epipubic bones, which are present in all other living mammals (marsupials and monotremes). This allows for expansion of the abdomen during pregnancy, though epipubic bones are present in many primitive eutherians. Eutheria was named in 1872 by Theodore Gill; in 1880, Thomas Henry Huxley defined it to encompass a more broadly defined group than Placentalia. The earliest unambiguous eutherians are known from the Early Cretaceous Yixian Formation of China, dating around 120 million years ago. Two tribosphenic mammals, ''Durlstodon'' and ''Durlstotherium'' from the Berriasian age (~145–140 million years ago) of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cokotherium
''Cokotherium'' is an extinct genus of eutherian mammal from the Early Cretaceous of China. It includes a single species, ''Cokotherium jiufotangensis'', known from a single partial skeleton, missing a portion of the hindlimbs and tail. It was recovered from the Jiufotang Formation (120 Ma), the upper part of the fossiliferous Jehol biota. The generic name of ''Cokotherium'' honors the nickname of the late paleontologist Chuan-Kui Li, a specialist on the Jiufotang Formation. The specific name refers to the formation in question''. Cokotherium'' is one of the youngest and most well-preserved Early Cretaceous eutherians, illustrating an array of transitional conditions between Early Cretaceous and Late Cretaceous members of Eutheria. Description Dentition The incisors, though conical and procumbent like other Early Cretaceous eutherians, are reduced in number; there are 4 in the upper jaw and 3 in the lower. Both the upper and lower canines are single-rooted, similar to met ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eomaia
''Eomaia'' ("dawn mother") is a genus of extinct fossil mammals containing the single species ''Eomaia scansoria'', discovered in rocks that were found in the Yixian Formation, Liaoning Province, China, and dated to the Barremian Age of the Lower Cretaceous about . The single fossil specimen of this species is in length and virtually complete. An estimate of the body weight is . It is exceptionally well-preserved for a 125-million-year-old specimen. Although the fossil's skull is squashed flat, its teeth, tiny foot bones, cartilages and even its fur are visible. Description The ''Eomaia'' fossil shows clear traces of hair. However, this is not the earliest clear evidence of hair in the mammalian lineage, as fossils of '' Volaticotherium'', and the docodont ''Castorocauda'', discovered in rocks dated to about , also have traces of fur. ''Eomaia scansoria'' possessed several features in common with placental mammals that distinguish them from metatherians, the group that include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protungulatum
''Protungulatum'' ('first ungulate') is an extinct genus of eutherian mammals within extinct family Protungulatidae, and is possibly one of the earliest known placental mammals in the fossil record, that lived in North America from the Late Cretaceous to early Paleocene.Maeva Orliac (2016."The inner ear of ''Protungulatum'' (Pan-Euungulata, Mammalia)"Journal of Mammalian Evolution 23(4) Fossils of this genus were first found in the Bug Creek Anthills in northeastern Montana. The Bug Creek Anthills were initially believed to be Late Cretaceous (latest Maastrichtian) because of the presence of the remains of non-avian dinosaurs and common Cretaceous mammals, but these were later shown to have been reworked from Late Cretaceous strata, and consequently the Bug Creek Anthills are currently believed to be Early Paleocene ( Puercan) in age. Remains from the Ravenscrag Formation of Saskatchewan, Canada have been assigned to ''Protungulatum donnae''. These remains may also be Cretace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zalambdalestes
''Zalambdalestes'' (meaning ''much-like-lambda robber'') is an extinct genus of eutherian mammal known from the Upper Cretaceous in Mongolia. Description ''Zalambdalestes'' was a hopping animal with a long snout, long teeth, a small brain and large eyes. It was about long, with a head only long. It had strong front paws and even stronger rear ones, sharing specializations to saltation similar to those of modern rabbits. It was most likely not a placental due to the presence of an epipubic bone, It had a unique axis that allowed for rapid movements, and in life it might have had spines or bristly fur. Biology Its diet was probably composed mainly of insects that it hunted in the forest undergrowth using its sharp, interlocking teeth. A well-preserved series of cervical vertebrae, including the axis, but not the atlas, seem to suggest vermivory. Unlike modern placental mammals, ''Zalambdalestes'' had an epipubic bone, meaning it was probably restricted reproductively in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cimolestes
''Cimolestes'' (from Ancient Greek , 'chalk robber') is a genus of early eutherians with a full complement of teeth adapted for eating insects and other small animals. Paleontologists have disagreed on its relationship to other mammals, in part because quite different animals were assigned to the genus, making ''Cimolestes'' a grade taxon of animals with similar features rather than a genus of closely related ones. Fossils have been found in North America, South America, Europe and Africa. ''Cimolestes'' first appeared during the Late Cretaceous of North America. According to some paleontologists, ''Cimolestes'' died out at the start of the Paleocene, while others report the genus from the early Eocene. Most species have been described from teeth and isolated fragments. One complete articulated skeleton provisionally assigned to ''Cimolestes'' has been found. It shows a small, agile, tree-dwelling predator with long toes for grasping branches and a prehensile tail at least twice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kennalestes
''Kennalestes'' is an extinct genus of insectivorous mammal resembling a shrew Shrews ( family Soricidae) are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to dif ... that was described in 1968.Z. Kielan-Jaworowska. 1968. New Upper Cretaceous multituberculate genera from Bayn Dzak, Gobi Desert. ''Palaeontologia Polonica'' The type species is ''K. gobiensis'' and it was a common mammal in Mongolia during the Cretaceous period, found in both the Bayan Mandahu Formation and Djadochta Formation. It was found in Mongolia during the Campanian, so it may have fallen victim to such predators as ''Velociraptor'', ''Oviraptor'' and ''Archaeornithoides''. References Extinct animals of Asia Leptictida Cretaceous mammals Fossil taxa described in 1968 Prehistoric mammal genera {{cretaceous-mammal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
