28-605: Rhomaleosauridae is a family of plesiosaurs from the Earliest Jurassic to the latest Middle Jurassic ( Hettangian to Callovian stages) of Europe , North America , South America and possibly Asia . Most rhomaleosaurids are known from England , many specifically from lower Blue Lias deposits that date back to the earliest Jurassic , just at the boundary with the Triassic . In fact, to date only two undisputed rhomaleosaurids were named from outside Europe -
56-586: A decade, still remaining undescribed, the specimen moved in the Royal Dublin Society museum and was officially described by Alexander Carte and W. H. Bailey as a new species of Plesiosaurus . Carte and Bailey named the species Plesiosaurus cramptoni after the Irish scientist, Sir Philip Crampton. In 1874, the British geologist Harry Govier Seeley , based on this finding, which is now known as
84-539: A fossil of a large plesiosaur was unearthed in an alum quarry at Kettleness , near Whitby, in Yorkshire, England. It was collected from the A. bifrons ammonite zone of the Whitby Mudstone Formation , dating to the early Toarcian age, about 183 to 180 million years ago. The complete skeleton which preserved the skull , NMING F8785, was kept for five years at Mulgrave Castle , which
112-465: A genus of plesiosaur that was described by palaeontologist Christian Erich Hermann von Meyer , back in 1841. Meyer described the species Thaumatosaurus oolithicus based on partial skull, vertebral and limb remains, that were found in the Posidonia Shale of Holzmaden , Baden-Württemberg , Germany . In 1856, Meyer published a full description of Thaumatosaurus and later provided figures of
140-554: A lack of widespread consensus within the scientific community for extended periods. The continual publication of new data and diverse opinions plays a crucial role in facilitating adjustments and ultimately reaching a consensus over time. The naming of families is codified by various international bodies using the following suffixes: The taxonomic term familia was first used by French botanist Pierre Magnol in his Prodromus historiae generalis plantarum, in quo familiae plantarum per tabulas disponuntur (1689) where he called
168-674: A nearly complete skull and vertebral column in association with parts of the limbs . It was in the early 1850s collected from the Alum Shale of Whitby Mudstone Formation, Yorkshire, dating from the Toarcian stage and donated in 1852 to the Yorkshire Philosophical Society by Lawrence Dundas, 1st Earl of Zetland , the Loftus mine owner. R. zetlandicus was first validly named by Phillips in 1854 and its skull
196-426: Is a stem-based taxon defined in 2010 (and in earlier studies in a similar manner) as "all taxa more closely related to Meyerasaurus victor than to Leptocleidus superstes , Pliosaurus brachydeirus or Polycotylus latipinnis ". Modern cladistic analyses are divided in the position of Rhomaleosauridae; some recover it at the base of Plesiosauria in a position basal to Neoplesiosauria that contains both
224-402: Is a junior synonym of Rhomaleosaurus zetlandicus . Smith and Gareth J. Dyke (2008) considered this species to be valid. R. thorntoni is known from the holotype BMNH R4853, three-dimensional, partially complete skeleton which preserved most of the skull and mandibles . It was collected by Henry Gerard Thornton from Kingsthorp of Northamptonshire , dating to the Toarcian stage. It
252-634: Is an extinct genus of Early Jurassic ( Toarcian age , about 183 to 175.6 million years ago) rhomaleosaurid pliosauroid known from Northamptonshire and from Yorkshire of the United Kingdom . It was first named by Harry Seeley in 1874 and the type species is Rhomaleosaurus cramptoni . It was one of the earliest large marine reptile predators which hunted in the seas of Mesozoic era , measuring about 7 metres (23 ft) long. Like other pliosaurs, Rhomaleosaurus fed on ichthyosaurs , ammonites and other plesiosaurs . In July 1848,
280-499: Is commonly referred to as the "walnut family". The delineation of what constitutes a family— or whether a described family should be acknowledged— is established and decided upon by active taxonomists . There are not strict regulations for outlining or acknowledging a family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to
308-485: Is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy . It is classified between order and genus . A family may be divided into subfamilies , which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae , but that family
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#1732787919064336-604: Is referred to Eurycleidus (or to a new genus by Smith and Dyke (2008)) and R. victor represents a new genus named Meyerasaurus by Smith and Vincent in 2010. Cladistic analyses by Ketchum & Benson, 2010, Benson et al. , 2011 and Ketchum & Benson, 2011 found R. megacephalus to be basal to the clade containing Rhomaleosaurus and Eurycleidus , thus it should be in its own genus as suggested by Smith and Dyke (2008). Following this, it has been placed in its own genus, Atychodracon . (Smith, 2015). The name Thaumatosaurus , which means 'wonder reptile', belonged to
364-438: Is the only well-known British Toarcian rhomaleosaurid discovered away from the Yorkshire coast, to date. R. thorntoni was first named by Andrews in 1922 and later revised by Cruickshank (1996) as a junior synonym of R. cramptoni , alongside R. zetlandicus . Adam S. Smith (2007) and Smith and Gareth J. Dyke (2008) considered this species to be valid. R. zetlandicus is known from the holotype YORYM G503 (pictured),
392-486: The Genera Plantarum of George Bentham and Joseph Dalton Hooker this word ordo was used for what now is given the rank of family. Families serve as valuable units for evolutionary, paleontological, and genetic studies due to their relatively greater stability compared to lower taxonomic levels like genera and species. Rhomaleosaurus thorntoni Rhomaleosaurus (meaning "strong lizard")
420-460: The A. serpentines ammonoid zone, of the Whitby Mudstone Formation , Yorkshire, England, dating to the middle Toarcian stage, about 180-177 million years ago . R. propinquus was first named by Tate and Blake in 1876 as a new species of Plesiosaurus . Watson (1910) redescribed it as a species of Rhomaleosaurus . Adam S. Smith (2007), in his thesis on the anatomy and classification of the family Rhomaleosauridae , suggested that R. propinquus ,
448-721: The pliosauroids and the plesiosauroids , while other analyses recover Rhomaleosauridae as pliosauroids , to the exclusion of Plesiosauroidea , either as the sister taxon of Pliosauridae or, rarely, as a paraphyletic array of taxa leading to it. Additionally, many putative rhomaleosaurids from the early deposits of Blue Lias , vary greatly in their position across various phylogenetic analyses . Some of these are recovered as basal rhomaleosaurids in certain analyses, or alternatively outside Rhomaleosauridae in more basal positions within Plesiosauria. The following two cladograms are simplified after two recent analyses, showing only
476-399: The type genus of the family Rhomaleosauridae , recognized and erected a new genus establishing Rhomaleosaurus . Only in 2006 the skull of this specimen was finally prepared which enabled a restudy of this genus. R. propinquus is known from the holotype WM 852.S, articulated almost complete skeleton which preserved the skull , exposed in dorsal view. It was collected from
504-458: The anatomy and classification of the family Rhomaleosauridae , the genus Rhomaleosaurus has only three valid species: R. cramptoni , R. thorntoni and R. zetlandicus . Smith and Dyke (2008) also recognized R. propinquus as valid. Other species that previously fell under this genus were: R. megacephalus and R. victor . Smith (2007) and Smith and Dyke (2008) pointed out that these species do not belong to Rhomaleosaurus , as R. megacephalus
532-582: The closely related Borealonectes russelli and Maresaurus coccai from Canada and Argentina , respectively. These two species are also the only Middle Jurassic representatives of the family. Rhomaleosauridae was formally named by Kuhn in 1961, originally proposed to include Rhomaleosaurus cramptoni and its relatives, which have short necks and large heads relatively to plesiosauroids like Elasmosaurus and Plesiosaurus , but longer necks and smaller heads relatively to advanced pliosaurids like Pliosaurus and Kronosaurus . Rhomaleosauridae
560-540: The family as a rank intermediate between order and genus was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes, disposés dans un ordre naturel (1796). He used families (some of them were not named) in some but not in all his orders of "insects" (which then included all arthropods ). In nineteenth-century works such as the Prodromus of Augustin Pyramus de Candolle and
588-430: The new species "Thaumatosaurus" victor. Many other researchers adopted the name "Thaumatosaurus". Today this taxon is regarded as a nomen dubium because the holotype can be referred to Pliosauroidea indet at best. The diagnostic specimens which previously were regarded as Thaumatosaurus' s specimens, now represent the holotypes of Eurycleidus , Meyerasaurus and Rhomaleosaurus . Smith & Dyke, 2008 redescribed
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#1732787919064616-1327: The relationships within Rhomaleosauridae, and some other relevant basal taxa whose position within the family is highly uncertain. Following Benson et al. (2012): Bobosaurus forojuliensis Anningasaura lymense Pliosauridae Plesiosauroidea Stratesaurus taylori Macroplata tenuiceps Avalonnectes arturi Eurycleidus arcuatus Meyerasaurus victor Maresaurus coccai Atychodracon megacephalus Archaeonectrus rostratus Rhomaleosaurus cramptoni Rhomaleosaurus thorntoni Rhomaleosaurus zetlandicus Following Benson & Druckenmiller (2014), with Macroplata and Eurycleidus excluded, and Borealonectes added: Bobosaurus forojuliensis Eoplesiosaurus antiquior Stratesaurus taylori Pliosauridae Plesiosauroidea Anningasaura lymense Avalonnectes arturi Atychodracon megacephalus Archaeonectrus rostratus Meyerasaurus victor Borealonectes russelli Maresaurus coccai Rhomaleosaurus thorntoni Rhomaleosaurus cramptoni Rhomaleosaurus zetlandicus [REDACTED] [REDACTED] [REDACTED] Family (biology) Family ( Latin : familia , pl. : familiae )
644-575: The seventy-six groups of plants he recognised in his tables families ( familiae ). The concept of rank at that time was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera , which is far from how the term is used today. In his work Philosophia Botanica published in 1751, Carl Linnaeus employed the term familia to categorize significant plant groups such as trees , herbs , ferns , palms , and so on. Notably, he restricted
672-1102: The skull of R. cramptoni after its final preparation. Both Rhomaleosauridae and Pliosauridae were found to be monophyletic, and the relations between Rhomaleosaurus' s species were tested. The cladogram below follows Smith & Dyke (2008), with the asterisk noting species removed from Rhomaleosaurus to their own genera since their study. Archaeonectrus rostratus Macroplata tenuiceps WARWKS G10875 → Unnamed species* Atychodracon megacephalus * LEICS G221.1851 referred to Atychodracon megacephalus * NMING F8749 referred to Atychodracon megacephalus * NMING F10194 referred to Atychodracon megacephalus * Eurycleidus arcuatus Sthenarosaurus dawkinsi Meyerasaurus victor * Maresaurus coccai Rhomaleosaurus propinquus Rhomaleosaurus zetlandicus Rhomaleosaurus cramptoni Rhomaleosaurus thorntoni Rhomaleosaurus may have been able to pick up scents while submerged by forcing water through passages in its skull containing sensory organs. This adaptation would have enabled it to hunt its prey in
700-451: The specimen. Richard Lydekker (1889) regarded Rhomaleosaurus as a synonym of Thaumatosaurus because Richard Lydekker and Harry G. Seeley "refused steadfastly to recognize the generic and specific names proposed by one another". Lydekker referred continuously to the name Thaumatosaurus , instead of Rhomaleosaurus . Fraas (1910) recognized both generic names in his original description of R. victor (now Meyerasaurus ), but referring to
728-549: The use of this term solely within the book's morphological section, where he delved into discussions regarding the vegetative and generative aspects of plants. Subsequently, in French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille was used as a French equivalent of the Latin ordo (or ordo naturalis ). In zoology ,
756-414: Was described in detail by Michael Alan Taylor in 1992. Later the taxon was revised by Cruickshank (1996) as a senior synonym of R. cramptoni , R. thorntoni being a junior synonym. Adam S. Smith (2007) and Smith and Gareth J. Dyke (2008) considered this species to be valid. Through the years, various species have been referred to as Rhomaleosaurus . However, according to Smith (2007), in his thesis on
784-531: Was then owned by the Marquess of Normanby . In 1853, the Marquess introduced the interesting finding to the eminent Irish surgeon and anatomist, Sir Philip Crampton . The same year, Crampton transferred the fossil to Dublin to be displayed as a centrepiece at the 1853 British Association annual meeting. The Zoological Society of Ireland built a specially constructed building to house the large reptile. After
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