The type species, Colobomycter pholeter, was first described from fossil remains in 1958, at which time it was believed to represent a synapsid, specifically, a pelycosaur.[1] However, the discovery of new material and reexamination of the holotype led to its reclassification as a member of the Eureptilia.[2] More recent studies indicate that Colobomycter is properly placed within the amniotecladeParareptilia, as part of the group Lanthanosuchoidea and closely related to the taxonAcleistorhinus.[3][4][5] A second species of Colobomycter was described in 2016, Colobomycter vaughni.[6]
No postcranial material is known for Colobomycter, and the skull material referred to the genus has all been recovered from a single locality, the Richards Spur site at the Dolese Brothers Limestone Quarry, 11 kilometers north of Fort Sill, Comanche County, Oklahoma, dating to the early Artinskian stage. This site comprises a fissure-fill deposit yielding a unique upland fauna.[3][4] Other taxa recovered from these strata preserves a wide array of tetrapods, including lepospondyl and temnospondyl amphibians, Seymouria, microsaurs, captorhinomorphs, and synapsids.
Descriptionedit
The skull of Colobomycter is considered one of the most enigmatic found in any of the parareptiles primarily due to the presence of greatly enlarged caniniform teeth possessing serrated edges in the premaxilla and, to a lesser extent, the maxilla.[4] The length of the premaxillary fang is greater than half the height of the skull. Modesto & Reisz (2008) note that "The large size of the first premaxillary tooth is [otherwise] unheard of among early reptiles." The taxon also possesses unusual "folding" of the dentine at the bases of its larger marginal teeth, a state known as polyplycodont (a condition also seen to have evolved independently in diadectomorphs, ichthyosaurs, and mosasaurs).[7] Modesto & Reisz (2008) speculate that hard-shelled insects and other arthropods may have formed the bulk of its diet, but that Colobomycter could also have fed on vertebrates, including small amphibians and eureptiles. It is notable as the smallest predatory amniote from the Richard's Spur deposits, with a skull measuring a mere 70-80 millimeters in length.[4]
Referencesedit
^Vaughn, P. P. (1958). "On a new pelycosaur from the Lower Permian of Oklahoma, and on the origin of the family Caseidae". Journal of Paleontology. 32: 981–991.
^Laurin, M.; Reisz, R. R. (1989). "Taxonomic position and phylogenetic relationships of Colobomycter pholeter, a small reptile from the Lower Permian of Oklahoma". Canadian Journal of Earth Sciences. 26 (3): 544–550. Bibcode:1989CaJES..26..544L. doi:10.1139/e89-046.
^ abModesto, S. P.; Reisz, R. R. (1999). "Colobomycter pholeter from the Lower Permian of Oklahoma: a parareptile, not a protorothyridid". Journal of Vertebrate Paleontology. 19 (3): 466–472. doi:10.1080/02724634.1999.10011159.
^ abcdModesto, S. P.; Reisz, R. R. (2008). "New material of Colobomycter pholeter, a small parareptile from the Lower Permian of Oklahoma". Journal of Vertebrate Paleontology. 28 (3): 677–684. doi:10.1671/0272-4634(2008)28[677:NMOCPA]2.0.CO;2.
^Macdougall, Mark J.; Scott, Diane; Modesto, Sean P.; Williams, Scott A.; Reisz, Robert R. (2017-07-01). "New material of the reptile Colobomycter pholeter (Parareptilia: Lanthanosuchoidea) and the diversity of reptiles during the Early Permian (Cisuralian)". Zoological Journal of the Linnean Society. 180 (3): 661–671. doi:10.1093/zoolinnean/zlw012. ISSN 0024-4082.
^MacDougall, Mark J.; Modesto, Sean P.; Reisz, Robert R. (2016-09-02). "A new reptile from the Richards Spur locality, Oklahoma, U.S.A., and patterns of Early Permian parareptile diversification". Journal of Vertebrate Paleontology. 36 (5): e1179641. doi:10.1080/02724634.2016.1179641. ISSN 0272-4634. S2CID 89333948.
^MacDougall, Mark J.; LeBlanc, Aaron R. H.; Reisz, Robert R. (2014-05-07). "Plicidentine in the Early Permian Parareptile Colobomycter pholeter, and Its Phylogenetic and Functional Significance among Coeval Members of the Clade". PLOS ONE. 9 (5): e96559. Bibcode:2014PLoSO...996559M. doi:10.1371/journal.pone.0096559. ISSN 1932-6203. PMC4013015. PMID 24804680.
External linksedit
from the Richard's Spur locality.
January 01, 1970
colobomycter, extinct, genus, lanthanosuchoid, parareptile, known, from, early, permian, oklahoma, temporal, range, early, permian, preꞒ, skull, diagram, pholeter, scientific, classification, domain, eukaryota, kingdom, animalia, phylum, chordata, class, repti. Colobomycter is an extinct genus of lanthanosuchoid parareptile known from the Early Permian of Oklahoma ColobomycterTemporal range Early Permian 289 Ma PreꞒ Ꞓ O S D C P T J K Pg N Skull diagram of Colobomycter pholeter Scientific classification Domain Eukaryota Kingdom Animalia Phylum Chordata Class Reptilia Clade Parareptilia Order Procolophonomorpha Family Acleistorhinidae Genus ColobomycterVaughn 1958 Type species Colobomycter pholeterVaughn 1958 Species C pholeter Vaughn 1958 type C vaughni MacDougall Modesto amp Reisz 2016 Contents 1 Discovery 2 Description 3 References 4 External linksDiscovery editThe type species Colobomycter pholeter was first described from fossil remains in 1958 at which time it was believed to represent a synapsid specifically a pelycosaur 1 However the discovery of new material and reexamination of the holotype led to its reclassification as a member of the Eureptilia 2 More recent studies indicate that Colobomycter is properly placed within the amniote clade Parareptilia as part of the group Lanthanosuchoidea and closely related to the taxon Acleistorhinus 3 4 5 A second species of Colobomycter was described in 2016 Colobomycter vaughni 6 No postcranial material is known for Colobomycter and the skull material referred to the genus has all been recovered from a single locality the Richards Spur site at the Dolese Brothers Limestone Quarry 11 kilometers north of Fort Sill Comanche County Oklahoma dating to the early Artinskian stage This site comprises a fissure fill deposit yielding a unique upland fauna 3 4 Other taxa recovered from these strata preserves a wide array of tetrapods including lepospondyl and temnospondyl amphibians Seymouria microsaurs captorhinomorphs and synapsids Description editThe skull of Colobomycter is considered one of the most enigmatic found in any of the parareptiles primarily due to the presence of greatly enlarged caniniform teeth possessing serrated edges in the premaxilla and to a lesser extent the maxilla 4 The length of the premaxillary fang is greater than half the height of the skull Modesto amp Reisz 2008 note that The large size of the first premaxillary tooth is otherwise unheard of among early reptiles The taxon also possesses unusual folding of the dentine at the bases of its larger marginal teeth a state known as polyplycodont a condition also seen to have evolved independently in diadectomorphs ichthyosaurs and mosasaurs 7 Modesto amp Reisz 2008 speculate that hard shelled insects and other arthropods may have formed the bulk of its diet but that Colobomycter could also have fed on vertebrates including small amphibians and eureptiles It is notable as the smallest predatory amniote from the Richard s Spur deposits with a skull measuring a mere 70 80 millimeters in length 4 References edit Vaughn P P 1958 On a new pelycosaur from the Lower Permian of Oklahoma and on the origin of the family Caseidae Journal of Paleontology 32 981 991 Laurin M Reisz R R 1989 Taxonomic position and phylogenetic relationships of Colobomycter pholeter a small reptile from the Lower Permian of Oklahoma Canadian Journal of Earth Sciences 26 3 544 550 Bibcode 1989CaJES 26 544L doi 10 1139 e89 046 a b Modesto S P Reisz R R 1999 Colobomycter pholeter from the Lower Permian of Oklahoma a parareptile not a protorothyridid Journal of Vertebrate Paleontology 19 3 466 472 doi 10 1080 02724634 1999 10011159 a b c d Modesto S P Reisz R R 2008 New material of Colobomycter pholeter a small parareptile from the Lower Permian of Oklahoma Journal of Vertebrate Paleontology 28 3 677 684 doi 10 1671 0272 4634 2008 28 677 NMOCPA 2 0 CO 2 Macdougall Mark J Scott Diane Modesto Sean P Williams Scott A Reisz Robert R 2017 07 01 New material of the reptile Colobomycter pholeter Parareptilia Lanthanosuchoidea and the diversity of reptiles during the Early Permian Cisuralian Zoological Journal of the Linnean Society 180 3 661 671 doi 10 1093 zoolinnean zlw012 ISSN 0024 4082 MacDougall Mark J Modesto Sean P Reisz Robert R 2016 09 02 A new reptile from the Richards Spur locality Oklahoma U S A and patterns of Early Permian parareptile diversification Journal of Vertebrate Paleontology 36 5 e1179641 doi 10 1080 02724634 2016 1179641 ISSN 0272 4634 S2CID 89333948 MacDougall Mark J LeBlanc Aaron R H Reisz Robert R 2014 05 07 Plicidentine in the Early Permian Parareptile Colobomycter pholeter and Its Phylogenetic and Functional Significance among Coeval Members of the Clade PLOS ONE 9 5 e96559 Bibcode 2014PLoSO 996559M doi 10 1371 journal pone 0096559 ISSN 1932 6203 PMC 4013015 PMID 24804680 External links editImages of a maxilla of Colobomycter pholeter from the Richard s Spur locality Retrieved from https en wikipedia org w index php title Colobomycter amp oldid 1214029674, wikipedia, wiki, book, books, library,
