obdurodon - Synonyms for obdurodon | Synonyms Of obdurodon

Examples of "obdurodon"
Obdurodon tharalkooschild is an extinct species of platypus in the genus "Obdurodon". It is known from a single tooth found at the Miocene-aged Two Tree Site fossil beds in Riversleigh in Queensland, Australia.
Obdurodon is an extinct monotreme genus containing four species. It is sometimes referred as the Riversleigh platypus, after the location of its discovery at Riversleigh. Individuals of "Obdurodon" differed from modern platypuses in that adult individuals retained their molar teeth (in the modern platypus, individuals lose all of their teeth upon reaching adulthood). Compared to the modern platypus, which is a mostly benthic forager, "Obdurodon" foraged "pelagically".
The Ornithorhynchidae are one of the two extant families in the order Monotremata, and contains the platypus and its extinct relatives. The other family is the Tachyglossidae, or echidnas. Within Ornithorhynchidae are two genera, "Obdurodon" and "Ornithorhynchus":
The evolution of monotreme eloctrolocation probably evolved in order to allow the animals to forage in murky waters, and may be tied to their tooth loss. The extinct "Obdurodon" was electroreceptive, but unlike the modern platypus it foraged pelagically.
Woodburne (2003, p. 212) reports that the holotype is a right mandible named AM F66763. The preserved molars are m1–m3. Page 237 includes: "In "Steropodon", the mandibular canal suggests the presence of a bill, with a bill also known in "Obdurodon dicksoni" and "Ornithorhynchus anatinus"."
A monotreme fossil of a jaw fragment 110 million years old were found at Lightning Ridge, New South Wales. These fragments, from the species "Steropodon galmani", are the oldest known fossils of monotremes. Fossils from the genera "Kollikodon", "Teinolophos", and "Obdurodon" have also been discovered. In 1991, a fossil tooth of a 61-million-year-old platypus was found in southern Argentina (since named "Monotrematum", though it is now considered to be an "Obdurodon" species). (See fossil monotremes below.) Molecular clock and fossil dating give a wide range of dates for the split between echidnas and platypuses, with one survey putting the split at 19–48 million years ago, but another putting it at 17–89 million years ago. All these dates are more recent than the oldest known platypus fossils, suggesting that both the short-beaked and long-beaked echidna species are derived from a platypus-like ancestor.
"Monotrematum sudamericanum", another fossil relative of the platypus, has been found in Argentina, indicating monotremes were present in the supercontinent of Gondwana when the continents of South America and Australia were joined via Antarctica (up to about 167 million years ago). A fossilized tooth of a giant platypus species, "Obdurodon tharalkooschild", was dated 5–15 million years ago. Judging by the tooth, the animal measured 1.3 meters long, making it the largest platypus on record.
The skull and nearly complete dentition of a fifteen million-year-old monotreme, "Obdurodon dicksoni", provide a window into the evolution of this characteristically Australian group. Fossil ancestors of the recently extinct thylacine, "Thylacinus cynocephalus", have also been identified among Riversleigh's fauna. In 1993, "Nimbadon" skulls were unearthed in a previously unknown cave in the region. Researchers estimate that the prehistoric marsupial first appeared about 15 million years ago and died out about 12 million years ago, perhaps from climate change induced losses in habitat. A well-preserved skull of the ancient "Nimbacinus dicksoni" marsupial found at Riversleigh has been used to determine the hunting behaviour of the species.
The time when the monotreme line diverged from other mammalian lines is uncertain, but one survey of genetic studies gives an estimate of about 220 million years ago. Fossils of a jaw fragment 110 million years old were found at Lightning Ridge, New South Wales. These fragments, from the species "Steropodon galmani", are the oldest known fossils of monotremes. Fossils from the genera "Teinolophos", and "Obdurodon" have also been discovered. In 1991, a fossil tooth of a 61-million-year-old platypus was found in southern Argentina (since named "Monotrematum", though it is now considered to be an "Obdurodon" species). (See fossil monotremes below.) Molecular clock and fossil dating give a wide range of dates for the split between echidnas and platypuses, with one survey putting the split at 19–48 million years ago, but another putting it at 17–89 million years ago. All these dates are more recent than the oldest known platypus fossils, suggesting that both the short-beaked and long-beaked echidna species are derived from a platypus-like ancestor. The earliest echidna found to date is about 13 million years.
"K. cadburyi" is distinguished by the authors from all extant monotremes, as well as from fossil tachyglossids, by the presence of a broad, marginated, shallow bicipital sulcus on the proximal humerus, which extends distally onto the waist of the bone. It is also distinguished by the presence of a trochlear-form ulnar articulation and a distal olecranon fossa. Pridmore "et al" find these features sufficient to distinguish it from "Steropodon" as well as other non-tachyglossid but similar monotremes such as "Obdurodon", "Kollikodon", "Teinolophos" and "Monotrematum". The bone itself measures a total length of 46 mm, though the authors point out that it is likely missing around an eighth of its true length and suffers from some amount of abrasion, and estimate the original length at around 50 mm in life.
The Ilariidae are a family of three species of extinct marsupials in two genera. They are all found in the middle Tertiary assemblage of South Australia, and are closely related to the family Phascolarctidae, which was found in Hamilton, Victoria. "I. illumidens" is the best-preserved representative of this extinct clade of vombatiforms. The species is found in the Namba Formation of late Oligocene age, Lake Pinpa, South Australia. The material consists of a partial cranium and mandibular fragments with most of the dentition, together with parts of the postcranial skeleton. The other species in this family are known from a few jaw fragments and intact molars attached; they are categorised in a separate family because their teeth structure is unique among Diprotodontia, in having a complicated folding pattern. Ilariids are thought to be the largest marsupials of their time in the Lake Eyre and Tarkarooloo basin, and lived along with Wynyardiidae, "Obdurodon", and thylacoleonids (marsupial lions) such as "Priscileo" and "Wakaleo".