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Paratomistoma
''Paratomistoma'' (meaning "next to or near ''Tomistoma''") is an extinct monospecific genus of gavialoid crocodylian. It is based on the holotype specimen CGM 42188, a partial posterior skull and lower jaw discovered at Wadi Hitan, Egypt, in Middle Eocene-age rocks of the Gehannam Formation. The skull is unfused but considered morphologically mature. ''Paratomistoma'' was named in 2000 by Christopher Brochu and Philip Gingerich; the type species is ''P. courti'' in honor of Nicholas Court, who found CGM 42188. They performed a phylogenetic analysis and found ''Paratomistoma'' to be a derived member of Tomistominae, related to the false gharial. It may have been a marine or coastal crocodilian. Below is a cladogram based morphological studies comparing skeletal features that shows ''Paratomistoma'' as a member of Tomistominae: Based on morphological studies of extinct taxa, the tomistomines were long thought to be classified as crocodiles and not closely relat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomistominae
Tomistominae is a subfamily of crocodylians that includes one living species, the false gharial. Many more extinct species are known, extending the range of the subfamily back to the Eocene epoch. In contrast to the false gharial, which is a freshwater species that lives only in southeast Asia, extinct tomistomines had a global distribution and lived in estuaries and along coastlines. The classification of tomistomines among Crocodylia has been in flux; while traditionally thought to be within Crocodyloidea, molecular evidence indicates that they are more closely related to true gharials as members of Gavialoidea. Description Tomistomines have narrow or longirostrine snouts like gharials. The living false gharial lives in fresh water and uses its long snout and sharp teeth to catch fish, although true gharials are more adapted toward piscivory, or fish-eating. Despite the similarity with gharials, the shapes of bones in tomistomine skulls link them with crocodiles. For example, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maroccosuchus
''Maroccosuchus zennaroi'' is an extinct gavialoid crocodylian from the Early Eocene of Morocco, traditionally regarded as a member of the subfamily Tomistominae. Below is a cladogram based on morphological studies comparing skeletal features that shows ''Maroccosuchus'' as a member of Tomistominae, related to the false gharial: Based on morphological studies of extinct taxa, the tomistomines were long thought to be classified as crocodiles and not closely related to gavialoids. However, recent molecular studies using DNA sequencing have consistently indicated that the false gharial (''Tomistoma'') (and by inference other related extinct forms in Tomistominae) actually belong to Gavialoidea (and Gavialidae). Below is a cladogram from a 2018 tip dating study by Lee & Yates simultaneously using morphological, molecular (DNA sequencing), and stratigraphic (fossil age) data that shows ''Maroccosuchus'' as an early-diverging gavialoid, more basal than the last common ancestor to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dollosuchoides
''Dollosuchoides'', colloquially known as the Crocodile of Maransart, is an extinct monospecific genus of gavialoid crocodilian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found in the Brussel Formation of Maransart, Belgium and date back to the middle Eocene. The holotype, IRScNB 482, was discovered in 1915 and it was prepared during 1926–1927 by M. Hubert, J. Mehschaert and M. Jean de Kleermaeker, and also in 1927, Louis Dollo had the holotype put on display in the Museum of Natural Sciences and he intended to describe the specimen but he died in 1931 before he was able to describe it and the specimen was eventually referred to '' Dollosuchus'' by Swinton (1937)Swinton, W. E. (1937)The Crocodile of Maransart (Dollosuchus dixoni [Owen]).''Mémoire'' 80: 3–46 until it was moved to its own genus by Brochu (2007). It is currently housed in the Gand Museum in Belgium. Phylogeny Below is a cladogram based morphological studies c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gavialoid
Gavialoidea is one of three superfamilies of crocodylians, the other two being Alligatoroidea and Crocodyloidea. Although many extinct species are known, only the gharial ''Gavialis gangeticus'' and the false gharial ''Tomistoma schlegelii'' are alive today, with ''Hanyusuchus'' having become extinct in the last few centuries. Extinct South American gavialoids likely dispersed in the mid Tertiary from Africa and Asia. Fossil remains of the Puerto Rican gavialoid '' Aktiogavialis puertorisensis'' were discovered in a cave located in San Sebastián, Puerto Rico and dated to the Oligocene. This individual is thought to have crossed the Atlantic coming from Africa, indicating that this species was able to withstand saltwater. Classification Gavialoidea is cladistically defined as ''Gavialis gangeticus'' (the gharial) and all crocodylians closer to it than to ''Alligator mississippiensis'' (the American alligator) or ''Crocodylus niloticus'' (the Nile crocodile). This is a stem-bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kentisuchus
''Kentisuchus'' is an extinct genus of gavialoid crocodylian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found from England and France that date back to the early Eocene. The genus has also been recorded from Ukraine, but it unclear whether specimens from Ukraine are referable to ''Kentisuchus''. Species The genus ''Kentisuchus'' was erected by Charles Mook in 1955 for the species ''"Crocodylus" toliapicus'', described by Richard Owen, in 1849. William Buckland named ''"Crocodylus" spenceri'' on the basis of a partial skull found from the Isle of Sheppey in Kent, England. In 1888 Richard Lydekker considered ''"C." toliapicus'' synonymous with ''"C." champsoides'' and ''"C." arduini'', named by De Zigno, and reapplied the name ''"C." spenceri'' to all of these species. The genus name ''Kentisuchus'' was constructed only after it was realized that these specimens were clearly distinct from the genus ''Crocodylus'' and that some specimens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toyotamaphimeia
''Toyotamaphimeia machikanensis'' (Toyotama-hime from Mountain Machikane ( :ja:待兼山)) is an extinct gavialid crocodylian which lived in Japan during the Pleistocene. A specimen recovered in 1964 at Osaka University during the construction of a new science building has been dated to around 430–380 thousand years old based on the stratum in which it was found. Unassigned species from same genus is also known from Taiwan. ''T. machikanensis'' was a fairly large crocodylian with a 1 m (3.3 ft) skull and a total length up to 7.7 m (25 ft). It was originally described as a member of the genus ''Tomistoma''. History and naming The first bones belonging to ''Toyotamaphimeia'' were discovered on May 3rd 1964 during the construction of a new school building on the grounds of Ôsaka University. A field survey was conducted shortly afterwards, confirming the presence of more fossils, however not yet identifying their crocodilian nature. Following the survey severa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penghusuchus
''Penghusuchus'' is an extinct genus of gavialid crocodylian. It is known from a skeleton found in Upper Miocene rocks of Penghu Island, off Taiwan. It may be related to two other fossil Asian gavialids: ''Maomingosuchus petrolica'' of southeastern China and '' Toyotamaphimeia machikanensis'' of Japan. The taxon was described in 2009 by Shan and colleagues; the type species is ''P. pani''. Below is a cladogram based morphological studies comparing skeletal features that shows ''Penghusuchus'' as a member of Tomistominae, related to the false gharial: Based on morphological studies of extinct taxa, the tomistomines (including the living false gharial) were long thought to be classified as crocodiles and not closely related to gavialoids. However, recent molecular studies using DNA sequencing have consistently indicated that the false gharial (''Tomistoma'') (and by inference other related extinct forms in Tomistominae) actually belong to Gavialoidea (and Gavialidae). Below is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomistoma
''Tomistoma'' is a genus of gavialid crocodilians. They are noted for their long narrow snouts used to catch fish, similar to the gharial. ''Tomistoma'' contains one extant (living) member, the false gharial (''Tomistoma schlegelii''), as well as potentially several extinct species: ''T. cairense'', ''T. lusitanicum'', ''T. taiwanicus'', ''T. coppensi'', and ''T. dowsoni''. However, these species may need to be reclassified to different genera as studies have shown them to be paraphyletic. Unlike the gharial, the false gharial's snout broadens considerably towards the base and so is more similar to those of true crocodiles than the gharial, whose osteology indicated a distinct lineage from all other living crocodilians.Piras, P., Colangelo, P., Adams, D. C., Buscalioni, A., Cubo, J., Kotsakis, T., & Raia, P. (2010). ''The Gavialis–Tomistoma debate: the contribution of skull ontogenetic allometry and growth trajectories to the study of crocodylian relationships''. Evoluti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thecachampsa
''Thecachampsa'' is an extinct genus of gavialoid crocodylian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found from the eastern United States in deposits of Miocene age. Those named in the 19th century were distinguished primarily by the shape of their teeth, and have since been combined with ''T. antiquus''. More recently erected species were reassigned from other genera, although their assignment to ''Thecachampsa'' has since been questioned. Description ''Thecachampsa'', like other "tomistomines" of the Oligocene and Miocene, was considerably larger than living crocodilians. Like living gharials, it had a long, slender snout. The teeth were long and recurved. Unlike its living relatives, ''Thecachampsa'' was marine, inhabiting estuaries and shallow coastal waters. Other marine fossils such as sea snail and bivalve shells, shark teeth, and barnacles have been found alongside remains of ''Thecachampsa'' and similar taxa. Species In 185 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
False Gharial
The false gharial (''Tomistoma schlegelii''), also known by the names Malayan gharial, Sunda gharial and tomistoma is a freshwater crocodilian of the family Gavialidae native to Peninsular Malaysia, Borneo, Sumatra and Java. It is listed as Vulnerable on the IUCN Red List, as the global population is estimated at around 2,500 to 10,000 mature individuals. The specific name ''schlegelii'' honors Hermann Schlegel. Taxonomy The scientific name ''Crocodilus (Gavialis) schlegelii'' was proposed by Salomon Müller in 1838 who described a specimen collected in Borneo. In 1846, he proposed to use the name ''Tomistoma schlegelii'', if it needs to be placed in a distinct genus. The genus ''Tomistoma'' potentially also contains several extinct species like ''T. cairense'', ''T. lusitanicum'', ''T. taiwanicus'', and ''T. coppensi''. However, these species may need to be reclassified to different genera as are paraphyletic. The false gharial's snout broadens considerably towards the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synapomorphy
In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have evolved in their most recent common ancestor. ) In cladistics, synapomorphy implies homology. Examples of apomorphy are the presence of erect gait, fur, the evolution of three middle ear bones, and mammary glands in mammals but not in other vertebrate animals such as amphibians or reptiles, which have retained their ancestral traits of a sprawling gait and lack of fur. Thus, these derived traits are also synapomorphies of mammals in general as they are not shared by other vertebrate animals. Etymology The word —coined by German entomologist Willi Hennig—is derived from the Ancient Greek words (''sún''), meaning "with, together"; (''apó''), meaning "away from"; and (''morphḗ''), meaning "shape, form". Clade analysis T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megadontosuchus
''Megadontosuchus'' is an extinct monospecific genus of gavialoid crocodylian, traditionally regarded as a member of Tomistominae, from the middle Eocene of Italy. Fossils have been found from Monte Duello in the province of Verona. The genus is currently monotypic, with the type and only species being ''Megadontosuchus arduini''. The species was originally named in 1880, although it was assigned to the genus ''Crocodilius'' (now spelled ''Crocodylus''). The genus was first erected by paleontologist Charles C. Mook in 1955 along with the genus ''Kentisuchus'', which was also first classified as ''Crocodilius''. No holotype for ''Megadontosuchus'' was designated in 1880, and a lectotype wasn't proposed until 2007. ''Megadontosuchus'' differs from other traditional "tomistomines" in that it has a more robust rostrum, very large teeth (hence the generic name meaning ''big-toothed crocodile''), and large supratemporal fenestrae on the skull table The skull roof, or the roofing bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
