|
Protocetid
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] |
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] |
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] |
Aegicetus
''Aegicetus'' is an extinct genus of protocetid whale based on a partial skull with much of an associated postcranial skeleton discovered in Egypt.Philip D. Gingerich, Mohammed Sameh M. Antar und Iyad S. Zalmot: "''Aegicetus gehennae'', a new late Eocene protocetid (Cetacea, Archaeoceti) from Wadi Al Hitan, Egypt, and the transition to tail-powered swimming in whales". ''PLoS ONE'' 14(12): e0225391 doi:10.1371/journal.pone.0225391 It lived around 35 million years ago (during the Late Eocene), making it the youngest known protocetid to date. ''Aegicetus'' was discovered in 2007 at Wadi El Hitan ( Gehannam Formation) as a relatively complete skeleton and a partial second specimen. They were assigned to a new genus and species in 2019 by Philip D. Gingerich ''et al.'' ''Aegicetus'' is reported to have been intermediate in form and functionally transitional in having a larger and more powerful vertebral column of a tail-powered swimmer. It differs from ''Peregocetus'' by lacking a f ... [...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 mole ... [...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] |
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 th ... [...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 wh ... [...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 USNM 392014, recovered in 1985 in a truck load of "marine marl" probably transported from New Bern, North Carolina, is two incomplete dentaries with a left P4 and broken M1-3; a right partial P4, partial M1-2, and a complete M3. The type locality is the Martin Marietta New Bern Quarry, Craven County, North Carolina ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dhedacetus
''Dhedacetus hyaeni'' is a protocetid cetacean from the middle Eocene (late Lutetian, 42 mya). It is the only species in the genus ''Dhedacetus''. The type specimen was recovered from the Indian Harudi Formation near the town of Dhedadi, Kutch. Description Only one skull and some vertebra are known. ''D. hyaeni'' is the smallest protocetid from Kutch. Its premolars and molars are about the same size as in other protocetids such as Babiacetus, Rodhocetus and Maiacetus. It has a long, broad snout and high ocular orbits. The genus name comes from the town close by and the species name comes from a local hyena Hyenas, or hyaenas (from Ancient Greek , ), are feliform carnivoran mammals of the family Hyaenidae . With only four extant species (each in its own genus), it is the fifth-smallest family in the Carnivora and one of the smallest in the clas .... References {{Archaeoceti Protocetidae Fossil taxa described in 2014 Prehistoric cetacean genera Fossils of India ... [...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] |
