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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] |
