Triconodontids can be distinguished from other eutriconodonts by the shape of their molars, which bore three main cusps of roughly equal size. During occlusion, the upper and lower molars interlocked tightly, producing a self-sharpening cutting edge. Historically, the triconodontids were thought to have a different occlusion pattern than other eutriconodonts, with the middle cusp of the lower molar (cusp a) fitting between the middle cusp (cusp A) and the front cusp (cusp B) of the upper molar, as in the basal mammaliaformMorganucodon.[3] However, a 2020 study on Priacodon suggests that triconodontids occluded their molars in the same manner as other eutriconodonts (so-called "embrasure occlusion"), with the middle cusp (cusp A/a) fitting between two opposing molars.[4]
Taxonomyedit
Triconodontidae was named by Marsh (1887). It was assigned to Polyprotodontia by Cope (1889); to Triconodonta by Rasmussen and Callison (1981), Bonaparte (1986), Carroll (1988) and Engelmann and Callison (1998); and to Mammalia by Marsh (1887) and Luo et al. (2001).[5]
Sometimes Volaticotheria is recovered as a part of this group.[1] However, other phylogenetic studies group it outside of Triconodontidae.[6][7]
^ abcGaetano, L. C.; Rougier, G. W. (2011). "New materials of Argentoconodon fariasorum (Mammaliaformes, Triconodontidae) from the Jurassic of Argentina and its bearing on triconodont phylogeny". Journal of Vertebrate Paleontology. 31 (4): 829–843. Bibcode:2011JVPal..31..829G. doi:10.1080/02724634.2011.589877. hdl:11336/68497. S2CID 85069761.
^Gaetano, L. C.; Rougier, G. W. (2012). "First Amphilestid from South America: A Molariform from the Jurassic Cañadón Asfalto Formation, Patagonia, Argentina". Journal of Mammalian Evolution. 19 (4): 235–248. doi:10.1007/s10914-012-9194-1. hdl:11336/68489. S2CID 254698557.
^ abButler, P. M.; Sigogneau-Russell, D. (2016). "Diversity of triconodonts in the Middle Jurassic of Great Britain" (PDF). Palaeontologia Polonica. 67: 35–65. doi:10.4202/pp.2016.67_035 (inactive 1 August 2023).{{cite journal}}: CS1 maint: DOI inactive as of August 2023 (link)
^Jäger, K. R. K.; Cifelli, R. L.; Martin, T. (2020). "Molar occlusion and jaw roll in early crown mammals". Scientific Reports. 10 (1): 22378. Bibcode:2020NatSR..1022378J. doi:10.1038/s41598-020-79159-4. PMC7759581. PMID 33361774.
^Luo, Z.-X.; Crompton, A. W.; Sun, A.-L. (2001). "A new mammaliaform from the Early Jurassic and evolution of mammalian characteristics". Science. 292 (5521): 1535–1540. Bibcode:2001Sci...292.1535L. doi:10.1126/science.1058476. PMID 11375489. S2CID 8738213.
^Martin, T.; Marugán-Lobón, J.; Vullo, R.; Martín-Abad, H.; Luo, Z.-X.; Buscalioni, A. D. (2015). "A Cretaceous eutriconodont and integument evolution in early mammals". Nature. 526 (7573): 380–384. Bibcode:2015Natur.526..380M. doi:10.1038/nature14905. PMID 26469049. S2CID 205245235.
^Averianov, A. O.; Lopatin, A. V. (2011). "Phylogeny of triconodonts and symmetrodonts and the origin of extant mammals". Doklady Biological Sciences. 436 (1): 32–35. doi:10.1134/s0012496611010042. PMID 21374009. S2CID 10324906.
December 20, 2023
triconodontidae, extinct, family, small, carnivorous, mammals, belonging, order, eutriconodonta, endemic, what, would, become, asia, europe, north, america, probably, also, africa, south, america, during, jurassic, through, cretaceous, periods, least, from, te. Triconodontidae is an extinct family of small carnivorous mammals belonging to the order Eutriconodonta endemic to what would become Asia Europe North America and probably also Africa and South America 1 2 during the Jurassic through Cretaceous periods at least from 190 70 6 mya 3 TriconodontidaeTemporal range Middle Jurassic Late Cretaceous 190 70 Ma PreꞒ Ꞓ O S D C P T J K Pg NTriconodon mordax jaw Richard Owen 1861Scientific classificationDomain EukaryotaKingdom AnimaliaPhylum ChordataClass MammaliaClade EutriconodontaFamily TriconodontidaeMarsh 1887Subgroups Eotriconodon Priacodon Triconodon type Trioracodon Victoriaconodon Alticonodontinae Alticonodon Arundelconodon Astroconodon Corviconodon Jugulator Meiconodon Volaticotherini Triconodontids can be distinguished from other eutriconodonts by the shape of their molars which bore three main cusps of roughly equal size During occlusion the upper and lower molars interlocked tightly producing a self sharpening cutting edge Historically the triconodontids were thought to have a different occlusion pattern than other eutriconodonts with the middle cusp of the lower molar cusp a fitting between the middle cusp cusp A and the front cusp cusp B of the upper molar as in the basal mammaliaform Morganucodon 3 However a 2020 study on Priacodon suggests that triconodontids occluded their molars in the same manner as other eutriconodonts so called embrasure occlusion with the middle cusp cusp A a fitting between two opposing molars 4 Taxonomy editTriconodontidae was named by Marsh 1887 It was assigned to Polyprotodontia by Cope 1889 to Triconodonta by Rasmussen and Callison 1981 Bonaparte 1986 Carroll 1988 and Engelmann and Callison 1998 and to Mammalia by Marsh 1887 and Luo et al 2001 5 Sometimes Volaticotheria is recovered as a part of this group 1 However other phylogenetic studies group it outside of Triconodontidae 6 7 Phylogeny editCladogram after Gaetano amp Rougier 2011 1 Triconodontidae PriacodonTriconodonTrioracodonAlticonodontinae ArundelconodonMeiconodonAstroconodonAlticonodonCorviconodonJugulatorVolaticotherini IchthyoconodonArgentoconodonVolaticotheriumReferences edit a b c Gaetano L C Rougier G W 2011 New materials of Argentoconodon fariasorum Mammaliaformes Triconodontidae from the Jurassic of Argentina and its bearing on triconodont phylogeny Journal of Vertebrate Paleontology 31 4 829 843 Bibcode 2011JVPal 31 829G doi 10 1080 02724634 2011 589877 hdl 11336 68497 S2CID 85069761 Gaetano L C Rougier G W 2012 First Amphilestid from South America A Molariform from the Jurassic Canadon Asfalto Formation Patagonia Argentina Journal of Mammalian Evolution 19 4 235 248 doi 10 1007 s10914 012 9194 1 hdl 11336 68489 S2CID 254698557 a b Butler P M Sigogneau Russell D 2016 Diversity of triconodonts in the Middle Jurassic of Great Britain PDF Palaeontologia Polonica 67 35 65 doi 10 4202 pp 2016 67 035 inactive 1 August 2023 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint DOI inactive as of August 2023 link Jager K R K Cifelli R L Martin T 2020 Molar occlusion and jaw roll in early crown mammals Scientific Reports 10 1 22378 Bibcode 2020NatSR 1022378J doi 10 1038 s41598 020 79159 4 PMC 7759581 PMID 33361774 Luo Z X Crompton A W Sun A L 2001 A new mammaliaform from the Early Jurassic and evolution of mammalian characteristics Science 292 5521 1535 1540 Bibcode 2001Sci 292 1535L doi 10 1126 science 1058476 PMID 11375489 S2CID 8738213 Martin T Marugan Lobon J Vullo R Martin Abad H Luo Z X Buscalioni A D 2015 A Cretaceous eutriconodont and integument evolution in early mammals Nature 526 7573 380 384 Bibcode 2015Natur 526 380M doi 10 1038 nature14905 PMID 26469049 S2CID 205245235 Averianov A O Lopatin A V 2011 Phylogeny of triconodonts and symmetrodonts and the origin of extant mammals Doklady Biological Sciences 436 1 32 35 doi 10 1134 s0012496611010042 PMID 21374009 S2CID 10324906 Retrieved from https en wikipedia org w index php title Triconodontidae amp oldid 1170210522, wikipedia, wiki, book, books, library,
