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Protocetidae
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] |
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 by the thir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aegyptocetus
''Aegyptocetus'' is an extinct genus of protocetid archaeocete whale known from Egypt. Taxonomy ''Aegyptocetus'' is known from the articulated holotype MSNTUP I-15459, an almost complete cranium, lower jaws (with teeth) and a partial postcranial skeleton (cervical and thoracic vertebrae and ribs). The specimen was recovered when marbleized limestone was imported commercially to Italy. It was collected in the Khashm el-Raqaba limestone quarry (, paleocoordinates ) from the Gebel Hof Formation on the northern flank of Wadi Tarfa in the Eastern Desert of Egypt, dating to the late Mokattamian age of the middle Eocene, about . Its cause of death may have been an attack by a large shark as pattern of shark tooth marks preserved on the ribs. ''Aegyptocetus'' was first named by Giovanni Bianucci and Philip D. Gingerich in 2011 and the type species is ''Aegyptocetus tarfa''. The generic name is derived from ''Aegyptus'', Latin for Egypt, and ''cetus'', Latin for whale. The s ... [...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, tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodhocetus
''Rodhocetus'' (from ''Rodho'', the geological anticline at the type locality, and ''cetus'', Latin for whale) is an extinct genus of protocetid early whale known from the Lutetian of Pakistan. The best-known protocetid, ''Rodhocetus'' is known from two partial skeletons that taken together give a complete image of an Eocene whale that had short limbs with long hands and feet that were probably webbed and a sacrum that was immobile with four partially fused sacral vertebrae. It is one of several extinct whale genera that possess land mammal characteristics, thus demonstrating the evolutionary transition from land to sea. Description left, Size of ''Rodhocetus'' relative to a human. ''Rodhocetus'' was a small whale measuring long. Throughout the 1990s, a close relationship between cetaceans and mesonychids, an extinct group of cursorial, wolf-like ungulates, was generally accepted based on morphological analyses. In the late 1990s, however, cladistic analyses based on molecula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Makaracetus
''Makaracetus'' is an extinct protocetid early whale the remains of which were found in 2004 in Lutetian layers of the Domanda Formation in the Sulaiman Range of Balochistan, Pakistan (, paleocoordinates ). ''Makaracetus'' is unique among archaeocetes in its feeding adaptations; its proboscis and the hypertrophied facial muscles. The generic epithet is a portmanteau of Makara, an elephant-headed sea monster from Hindu mythology, and ''cetus'', Greek for "whale". The species epithet, ''bidens'', is Greek for "two-teeth", in reference to the retention of only two incisors in each premaxilla. ''Makaracetus''' unique features even lead to propose a new classification of Protocidae based on the degree of their aquatic adaptation; with ''Makarcetus'' alone in the subfamily Makaracetinae. A combination of cranial features indicates that ''Makaracetus'' had a short, muscular proboscis similar to a tapir. There are broad and shallow narial grooves on the dorsal side of the premax ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georgiacetus BW
''Georgiacetus'' is an extinct genus of ancient whale known from the Eocene period of the United States. Fossils are known from Georgia, Alabama, and Mississippi and protocetid fossils from the right time frame, but not yet confirmed as ''Georgiacetus'', have been found in Texas () and South Carolina (). created a new clade, Pelagiceti, for the common ancestor of Basilosauridae and all of its descendants, including Neoceti, the living cetaceans. He placed ''Georgiacetus'' near the base of this clade together with ''Eocetus'' and perhaps ''Babiacetus'' because of the assumed presence of a fluke and very compressed posterior caudal vertebrae in these genera. ''Georgiacetus'' is an extinct protocetid (early whale) which lived about and hunted the rich, Suwannee Current powered coastal sea which once covered the Southeastern United States. This was during the earliest Bartonian Stage of the Eocene Epoch (). Current research puts ''Georgiacetus'' as the link between the protoc ... [...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] |
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 ''an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qaisracetus
''Qaisracetus'' is an extinct Protocetidae, protocetid Archaeoceti, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetacea
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 themselves through the water with powerful up-and-down movement of their tail which ends in a paddle-like fluke, using their flipper-shaped forelimbs to maneuver. While the majority of cetaceans live in marine environments, a small number exclusively reside in brackish water or fresh water. Having a cosmopolitan distribution, they can be found in some rivers and all of Earth's oceans, and many species inhabit vast ranges where they migrate with the changing of the seasons. Cetaceans are famous for their high intelligence and complex social behaviour as well as for the enormous size of some of the group's members, such as the blue whale which reaches a maximum confirmed length of 29.9 meters (98 feet) and a weight of 173 tonnes (190 short to ... [...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'' and ''Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crenatocetus
''Crenatocetus'' (from Latin: ''crena'', "notch", and ''cetus'', "whale") is an extinct genus of protocetid early whale containing one species, ''Crenatocetus rayi'', that lived along the Atlantic Coastal Plain of the United States during the Lutetian in the late middle Eocene. The species is named in honour of paleontologist Clayton E. Ray, former curator at the National Museum of Natural History. The skull is estimated to be long, which makes ''Crenatocetus'' a mid-sized protocetid. ''Georgiacetus'' (from Georgia) is an older and more primitive close relative, while '' Pappocetus'' (from Nigeria) is a younger and more derived relative. The holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of sever ... USNM 392014, recovered in 1985 in a truck load of "marine marl" probably t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
