|
Protocetinae
Protocetidae, the protocetids, form a diverse and heterogeneous group of extinct cetaceans known from Asia, Europe, Africa, South America, and North America. Description There were many genera, and some of these are very well known (e.g., ''Rodhocetus''). Known protocetids had large fore- and hindlimbs that could support the body on land, and it is likely that they lived amphibiously: in the sea and on land. It is unclear at present whether protocetids had flukes (the horizontal tail fin of modern cetaceans). However, what is clear is that they are adapted even further to an aquatic life-style. In ''Rodhocetus'', for example, the sacrum – a bone that in land-mammals is a fusion of five vertebrae that connects the pelvis with the rest of the vertebral column – was divided into loose vertebrae. However, the pelvis retain a sacroiliac joint. Furthermore, the nasal openings are now halfway up the snout; a first step towards the telescoped condition in modern whales. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Eocene
In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by the Eocene Lutetian Age. The Ypresian is consistent with the lower Eocene. Events The Ypresian Age begins during the throes of the Paleocene–Eocene Thermal Maximum (PETM). The Fur Formation in Denmark, the Messel shales in Germany, the Oise amber of France and Cambay amber of India are of this age. The Eocene Okanagan Highlands are an uplands subtropical to temperate series of lakes from the Ypresian. Stratigraphic definition The Ypresian Stage was introduced in scientific literature by Belgium, Belgian geologist André Hubert Dumont in 1850. The Ypresian is named after the Flanders, Flemish city of Ypres in Belgium (spelled ''Ieper'' in Dutch). The definitions of the original stage were totally different from the modern ones. The Ypresi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artiocetus
''Artiocetus'' is an extinct genus of early whales belonging to the family Protocetidae. It was a close relative to '' Rodhocetus'' and its tarsals indicate it resembled an artiodactyl. Etymology ''Artiocetus''' name arises from a combination of cetus and artiodactyl, as this fossil was the first to show that early whales possessed artiodactyl-like ankles. ''Artiocetus'' belongs to the infraorder Cetacea, which includes whales, dolphins and porpoises. Cetus is a Latinized Greek word literally meaning "sea monster" and is used in biological names to mean "whale". It comes from Ancient Greek κῆτος (kētos), in reference to the sea monster goddess Ceto, daughter of Gaia and Pontus, and said to resemble a gigantic whale or fish. Artiodactyla refers to the mammal order of even-toed ungulates the group containing cattle, deer, camels, giraffes, antelope, goats, sheep, pigs and hippopotamuses. If the animal has even number of toes, the weight is borne equally b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basilosauridae
Basilosauridae is a family of extinct cetaceans. They lived during the middle to the early late Eocene and are known from all continents, including Antarctica. They were probably the first fully aquatic cetaceans.Buono M, Fordyce R.E., Marx F.G., Fernández M.S. & Reguero M. (2019). "Eocene Antarctica: a window into the earliest history of modern whales". ''Advances in Polar Science'' 30(3): p. 293-302. doi10.13679/j.advps.2019.0005/ref> The group is noted to be a paraphyletic assemblage of stem group whales from which the monophyletic Neoceti are derived. Characteristics Basilosaurids ranged in size from and were fairly similar to modern cetaceans in overall body form and function. Some genera tend to show signs of convergent evolution with mosasaurs by having long serpentine body shape, which suggests that this body plan seems to have been rather successful. Basilosaurid forelimbs have broad and fan-shaped scapulae attached to a humerus, radius, and ulna which are fla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bartonian
The Bartonian is, in the ICS's geologic time scale, a stage or age in the middle Eocene Epoch or Series. The Bartonian Age spans the time between . It is preceded by the Lutetian and is followed by the Priabonian Age. Stratigraphic definition The Bartonian Stage was introduced by Swiss stratigrapher Karl Mayer-Eymar in 1857. The name derives from the coastal village Barton-on-Sea (part of New Milton) in southern England. The Barton Group, a lithostratigraphic unit from the south English Hampshire Basin, is of Bartonian age. The distinction between group and stage was made in the second part of the 20th century, when stratigraphers saw the need to distinguish between litho- and chronostratigraphy. The base of the Bartonian is at the first appearance of the calcareous nanoplankton species ''Reticulofenestra reticulata''. In 2009, an official reference profile (GSSP) for the base of the Bartonian had not yet been established. The top of the Bartonian Stage (the ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Togocetus
''Togocetus'' (“Togo whale”) is a genus of extinct cetacean from the Lutetian (lower Eocene) of Togo, known from a fossilized skeleton discovered a few kilometers north-east of Lomé. Discovery and description The skeleton was found in a phosphate mining area, Kpogamé-Hahotoé, which is located just north of Lake Togo. It was embedded in a phospharenite bone bed dating back to 46 – 44 million years ago, and overlying an older rock unit, the Tabligbo Group. The remains were described in 2014 by Philip D. Gingerich and Henri Cappetta, who established for it the new monotypic genus ''Togocetus'' and the new species ''T. traversei'', dedicated to Michel Traverse. According to the two authors, ''Togocetus'' was a semiaquatic animal which must have weighed around . It was a protocetid with rather primitive traits such as a still quite long neck, a digitigrade manus and a swim-specialized pes. It shared many similarities with the protocetid genera '' Protocetus'' a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Takracetus
''Takracetus'' was a primitive cetacean Cetacea (; , ) is an infraorder of aquatic mammals that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel them ... that lived approximately . The type specimen (GSP-UM 3041) is a partial skull though the literature mentions a second more complete specimen. Notes References * * Protocetidae Prehistoric cetacean genera Fossil taxa described in 1995 Extinct mammals of Asia {{paleo-whale-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qaisracetus
''Qaisracetus'' is an extinct protocetid early whale known from the Eocene (Lutetian, ) of Baluchistan, Pakistan (, paleocoordinates ). Etymology The genus is named after the Qaisrani Baloch tribe which assisted Gingerich and his team during their field work. "Qaisra" is also etymologically close to the royal title used in Persian and many Indo-European languages (e.g. Kaiser, Czar, Caesar). The species is named for Muhammad Arif, former paleontologist at the Geological Survey of Pakistan who contributed significantly to archaeocete paleontology in Pakistan. Description ''Qaisracetus'' is known from a dozen specimens, all found in or near the type locality. Among them are several well-preserved elements, including a well-preserved skull, partial skulls and braincases, several vertebrae including an almost complete sacrum, a left innominate, ribs, and partial limb elements. ''Qaisracetus'' is smaller than ''Pappocetus'' and ''Babiacetus'' but larger than ''Indocetus''. ''Qai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protocetus
''Protocetus atavus'' ("first whale") is an extinct species of primitive cetacean from Egypt. It lived during the middle Eocene period 45 million years ago. The first discovered protocetid, ''Protocetus atavus'' was described by based on a cranium and a number of associated vertebrae and ribs found in middle Lutetian Tethyan marine limestone from Gebel Mokattam near Cairo, Egypt. Description ''Protocetus'' are believed to have had a streamlined, whale-like body around long, but was probably primitive in some respects.Palmer D (ed.) (1999). ''The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals''. London: Marshall Editions. p. 230. . Many protocetids (like ''Maiacetus'', ''Rodhocetus'') possessed well developed innominates and hind limbs, often attached to the backbone with a sacrum. ''Protocetus'' are known to have had at least one sacral vertebrate,Gingerich P.D. (2010). "Cetacea". In Werdelin L & Sanders W.J. (eds.). ''Cenozoic mammals of africa''. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phiomicetus
''Phiomicetus'' is a genus of protocetid whale that lived between 43 and 42 million years ago during the middle Eocene in what is now Egypt. It had powerful jaws and large teeth that would have allowed it to hunt and tear large prey. Discovery and naming ''Phiomicetus'' was unearthed in 2008 at Al Amaim, which lies on the southern margin of Wadi Al-Ruwayan in the Fayum Depression, in the Western Desert of Egypt. The holotype specimen, MUVP500, is the partial skeleton of a single individual that includes the cranium, right mandible, an incomplete left mandible, several teeth, fifth cervical vertebra, sixth thoracic vertebra, sixth left rib, and an isolated right rib. ''Phiomicetus'' is the first extinct whale to be discovered, scientifically described, and named by a team of Arab paleontologists. The generic name ''Phiomicetus'' is derived from the Fayum Depression, the type locality where it was discovered, and the Latin term ''cetus'' meaning "whale". The specific name ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peregocetus
''Peregocetus'' is a genus of early whale that lived in what is now Peru during the Middle Eocene epoch. Its fossil was uncovered in 2011 in the Yumaque Formation of the Pisco Basin at Playa Media Luna by a team consisting of members from Belgium, Peru, France, Italy, and the Netherlands. Parts recovered include the jaw, front and hind legs, bits of spine, and tail. Olivier Lambert, a scientist at the Royal Belgian Institute of Natural Sciences and lead author of the study, noted that ''Peregocetus'' "fills in a crucial nowledgegap" about the evolution of whales and their spread. ''Peregocetus'' is the first recorded quadrupedal whale from the Pacific Ocean and the Southern Hemisphere. The discovery reveals that protocetids reached the Pacific Ocean and attained a near circumequatorial distribution while retaining functional weight-bearing limbs. Description ''Peregocetus'' was essentially a four-legged whale: however, it had webbed feet with small hooves on the tips of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kharodacetus
''Kharodacetus'' is a genus of protocetid cetacean from the middle Eocene (late Lutetian, 42 mya) of Kutch, Gujarat, southwestern India. Description ''Kharodacetus'' is a large-sized protocetid with large premolars and a flat supraorbital shield with large orbits (eye sockets). Its snout is long and relatively broad, (though the snout is narrower in '' Gaviacetus'' and ''Makaracetus'', broader in ''Takracetus''), its orbit is high above the palate, and the premolars are large and robust. The molars have a large protocone (unlike ''Babiacetus'') and a large metacone (unlike ''Maiacetus ''Maiacetus'' ("mother whale") is a genus of early middle Eocene (c. 47.5 mya) cetacean from the Habib Rahi Formation of Pakistan. Paleobiology The genus contains a single species, ''Maiacetus inuus'', first described in 2009 on the basis of ...''), and are, relative to P4, longer than in other protocetids. Classification ''Kharodacetus'' was originally described as a species of '' Gaviace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indocetus
''Indocetus'' is a protocetid early whale known from the late early Eocene (Lutetian, ) Harudi Formation (, paleocoordinates ) in Kutch, India. The holotype of is a partial skull in two pieces with the frontal shield and the right occiput and auditory bulla preserved. described postcranial remains from the Sulaiman Range, Punjab, Pakistan, and attributed them to ''Indocetus''. , however, withdrew this assignment and instead attributed this postcranial material to ''Remingtonocetus'' because of similarities to the then newly discovered remingtonocetid ''Dalanistes'', including a longer neck and fused sacral vertebral elements. This leaves ''Indocetus'' without postcranial remains, but undescribed material (as of 1998) from Kutch most likely include some that can be attributed to ''Indocetus''. Furthermore, ''Rodhocetus'', also from Sulaiman, is very similar to ''Indocetus'' and it is possible that these genera are synonyms. ''Indocetus'' is known from a partial skull, two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
