Abrahamskraal Formation

Last updated
Abrahamskraal Formation
Stratigraphic range: Wordian-Capitanian
~268–259  Ma
Hill at Karoo National Park.png
Hill with outcropping Teekloof and Abrahamskraal Formations
Type Geological formation
Unit of Beaufort Group
Sub-units Tapinocephalus Assemblage Zone, Eodicynodon Assemblage Zone
Underlies Teekloof Formation
Overlies Ecca Group
Thicknessup to 2,565 m (8,415 ft)
Lithology
Primary Mudstone, sandstone
Other Siltstone
Location
Coordinates 31°24′S23°06′E / 31.400°S 23.100°E / -31.400; 23.100
Approximate paleocoordinates 59°54′S38°54′W / 59.9°S 38.9°W / -59.9; -38.9
Region Northern, Western & Eastern Cape
Country South Africa
Type section
Named forAbrahams Kraal 29 (farm), 18 km south of Leeu-Gamka
Named byA.W. Keyser, P.J. Rossouw & Lieuwe Dirk Boonstra
Geology of Karoo Supergroup.png
A simplified geological map of the outcrops of Karoo Supergroup rocks in Southern Africa. The Beaufort Group is represented by the yellow key on the map.

The Abrahamskraal Formation is a geological formation and is found in numerous localities in the Northern Cape, Western Cape, and the Eastern Cape of South Africa. It is the lowermost formation of the Adelaide Subgroup of the Beaufort Group, a major geological group that forms part of the greater Karoo Supergroup. It represents the first fully terrestrial geological deposits of the Karoo Basin. Outcrops of the Abrahamskraal Formation are found from the small town Middelpos in its westernmost localities, then around Sutherland, the Moordenaarskaroo north of Laingsburg, Williston, Fraserburg, Leeu-Gamka, Loxton, and Victoria West in the Western Cape and Northern Cape. In the Eastern Cape outcrops are known from Rietbron, north of Klipplaat and Grahamstown, and also southwest of East London. [1] [2]

Contents

Geology

The Abrahamskraal Formation comprises the majority of the Middle Permian Beaufort sequence, and are thought to range between 268 - 259 million years in age. The lowermost deposits of the Abrahamskraal Formation found in the Eastern Cape until recently were named the Koonap Formation, but these outcrops have been amalgamated into the Abrahamskraal Formation due to recent stratigraphic and biostratigraphic research. [3] The Abrahamskraal Formation incorporates the entire Tapinocephalus Assemblage Zone in its upper sections and the entire Eodicynodon Assemblage Zone its lowermost southern deposits. In the west and northerly deposits the Abrahamskraal Formation overlies the Waterford Formation and the Middleton Formation in the south, both formations containing the uppermost deposits of the Ecca Group.

The rocks of the Abrahamskraal Formation comprise mainly greenish-grey to blueish-grey mudstone coupled with rarer instances of greyish-red, reddish-brown or purple mudstones. These include subordinate greenish-grey, fine-grained sandstones which are normally observed in fining upward cycles. The sandstones vary in thickness from several metres to several tens of metres in some localities. Siltstones are also found interbedded with the mudstone beds. The presence of these rocks reveal much about the past environment that they were deposited in. They were formed by sedimentary material being deposited in the Karoo Basin - a retro-arc foreland basin - by vast, low-energy alluvial plains flowing northwards from the south. The lowermost deposits are considered to be deltaic and grade laterally into the underlying Ecca Group deposits in its southern localities. Deposits grade steadily younger in the northeast where the sedimentary facies turn fully terrestrial. The greenish-grey mudstones are usually associated with the deltaic sedimentary facies while the redder mudstones with the terrestrial. [4] [5] [6] [7]

All sedimentary rocks of the Karoo Basin were transported downhill from the south in the shadow of the rising Gondwanide mountain range. The Gondwanides were the result of tectonic uplift that had previously begun to take course due to subduction of the Palaeo-pacific plate beneath the Gondwanan Plate. Orogenic pulses from the growing Gondwanides mountain chain and associated subduction created accommodation space for sedimentation in the Karoo Basin where the deposits of the Abrahamskraal Formation and all succeeding deposits of the Karoo Basin were deposited over millions of years. [8] [9] [10] [11] [12] [13] [14]

Paleontological significance

The Abrahamskraal Formation is highly fossiliferous and well known for its biozone assemblages of therapsid fossils. [15] [16] [17] [18] The Eodicynodon and Tapinocephalus Assemblage Zones to which this geological formation incorporates preserve the first appearance of the earliest dicynodonts, dinocephalians, biarmosuchians, therocephalians, gorgonopsians, [19] [20] and pareiasaurian parareptiles. [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] The upper sections of this formation document the rise of and diversification of the dinocephalians. [33] [34] [35] [36] [37] The dinocephalians subsequently went extinct at the contact of the Abrahamskraal Formation with the overlying Teekloof Formation. [38] [39] [40] The basal pelycosaur synapsid species, Elliotsmithia longiceps , has also been found in the deposits of this formation. [41] [42] [43] The presence of this basal synapsid is indicative of this geological formations significance. For decades, paleontologists have puzzled over what has been termed Olsen’s Gap, which is used to describe the evolutionary gap in the tetrapod fossil record between the appearance of the more derived therapsids and their ancestors, the pelycosaurs. The rocks of the Abrahamskraal Formation and its geological correlates abroad hold the promise of that fossil gap being bridged through future research endeavors in the years to come. More notable fossil species include the dicynodont Diictodon feliceps which first appears in the upper sections of this formation, remaining ubiquitous until the Permian-Triassic boundary. [44] [45] [46] Finally, fossils of temnospondyl amphibians such as of Rhinesuchus , the fish Namaichthys, invertebrate fossils of molluscs, invertebrate trackways and burrows, vertebrate footprints of therapsids, and a variety of plant fossils such as Dadoxylon , Equisetum modderdriftensis , Schizoneura africana, and several different species of Glossopteris have been recovered. [47] [48]

Among the species found in the Abrahamskraal Formation is Moschops Capensis [49]

Paleobiota

Color key
Taxon Reclassified taxonTaxon falsely reported as presentDubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Amphibians

Amphibians of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Rhinesuchus [50] R. tenucepsFarm Stinkfontein, Prince Albert DistrictTapinocephalus A-Z.A skull associated with a partial left mandibular ramus.A temnospondyl amphibian. Rhinesuchus1DB.jpg
R. whaitsiLeeu-Gamka, Prince Albert DistrictA basicranium, seven fragments of the middle portion of the left hemi-mandible, and multiple skull fragments.

Fish

Actinopterygian
Actinopterygians of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Bethesdaichthys B. kitchingiBlourug farm, Victoria West.Tapinocephalus A-ZA preserved skull.An actinopterygian fish.
Blourugia [51] B. seeleyiBlourug farm, Victoria West.Tapinocephalus A-ZA partial skeleton.An actinopterygian fish.
Westlepis W. kempeniBlourug farm, Victoria WestTapinocephalus A-ZAn actinopterygian fish.

Reptiles

Sauropsida

Sauropsids of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Australothyris A. smithiBeukesplaas farmUpper part of Tapinocephalus A-ZA skull and portions of the rest of the skeletonA parareptile.
Bradysaurus B. bainiPrince Albert, Leeu Gamka, Hottentotsrivier Farm, Leeurivier, Mynhardtskraal, Groot Kruidfortein, Zwarts Siding, Sutherland, and Knoffelfortein.Tapinocephalus A-ZA complete skull and separate lower jaw with a complete postcranial skeleton consisting of a complete shoulder girdle and pelvis, a complete vertebral column with few missing at the end of the caudal vertebrae. The right fore and hind limbs are complete. The left humerus, radius, ulna, femur, tibia, and fibula are partially preserved.A pareiasaur. Bradysausus baini copia.jpg
B. seeleyiA partial skeleton consists of a complete skull, lower jaw, partial vertebral column, some ribs, osteoderms, and parts of girdles. Bradysaurus seeleyi 2 copia.jpg
Embrithosaurus E. schwarziHoogeveld farm.Tapinocephalus A-ZDistorted skull with the occluded lower jaw, vertebrae 1 to 27 with articulated osteoderms, two small articulated caudal vertebrae, partial left scapulocoracoid, cleithrum, left and right clavicle, and interclavicle, complete right humerus, partial left humerus, complete right radius, partial left radius, both ulnae complete, both femora complete, both tibia complete, right fibula, partial left fibula, complete pelvis, two digits of the forelimb and two digits of the hindlimbA pareiasaur.
Eunotosaurus E. africanusDe bad farm, Prince Albert, Boesmanrivier and RietfortienUpper Tapinocephalus A-Z and parts of Pristerognathus A-Z.Fossilized ribbones.An early relative of reptile. Eunotosaurus africanus.jpg

Synapsids

Therapsids

Anomodonts
Chainosauria
Chainosaurs of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Galechirus G. scholtzlVictoria WestTapinocephalus A-Z.A partial skeletonAn insectivorous anomodont.
Galechirus1DB.jpg
Patranomodon P. nyaphuliiPrince AlbertEodicynodon A-ZA fossilized skullA rare genus of anomodont.
Patranomodon.jpg
Dicynodontia
Dicynodonts of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Brachyprosopus B. broomiBeukesplaasTapinocephalus A-ZA skull.A dicynodont.
Brachyprosopus broomi Brachyprosopus broomi.png
Brachyprosopus broomi
Diictodon Feliceps Diictodon EF.jpg
Diictodon Feliceps
Emydops Arctatus Emydops skull.jpeg
Emydops Arctatus
Eodicynodon oosthuizeni Eodicynodon oosthuizeni.png
Eodicynodon oosthuizeni
Eosimops newtoni Eosimops newtoni.png
Eosimops newtoni
Nyaphulia oelofseni Nyaphulia snout and skull roof.jpg
Nyaphulia oelofseni
Robertia broomiana Robertia1DB.jpg
Robertia broomiana
Colobodectes [52] C. cluveriKeerom farm, Kruidfontein farm, Bastardsfontein farm, and Altringham farm.Eodicynodon and Tapinocephalus A-ZA skull lacking zygomatic arches and postorbital barsA dicynodont.
Diictodon D. felicepsPrince Albert.Tapinocephalus A-ZSeveral skeletal specimens.A pylaecephalid dicynodont.
Emydops E. arctatusBeaufort West and Prince Albert.Either Tapinocephalus A-Z or Pristerognathus A-Z.A partial skullA dicynodont.
Eodicynodon [53] E. oosthuizeniTuinkraal and Zwartskraal farm, Prince Albert districtTapinocephalus A-ZPostcranial skeleton.A dicynodont.
Eosimops E. newtoniVictoria West.Tapinocephalus A-Z.several skull specimens and one complete skeleton.A pylaecephalid dicynodont.
Nyaphulia [53] N. oelofseniBotterkraal farmEodicynodon A-Z.Partial skull, jaws, and teeth.A dicynodont, formally named E. oelofseni.
Robertia R. broomianaKlein Koedoeskop, Beaufort West.Lower part of the Tapinocephalus A-Z.Partial skull and postcranial skeleton.A small herbivorous dicynodont.
Biarmosuchia
Biarmosuchians of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Hipposaurus H. boonstraiBeaufort west and Riet FonteinTapinocephalus A-ZA single skull.A hipposaurid therapsid.
Hipposaurus.jpg
H. brinkiA preserved skull.
Impumlophantsi [54] I. boonstraiPalmietfontein portion (plot 57) of Kruidfontein farm, Prince Albert DistrictTapinocephalus A-ZThe preorbital region of the skull and articulated lower jaw and a partial vertebral column and pelvisA Biarmosuchian.
Impumlophantsi boonstrai.png
Nierkoppia N. bruceiFarm StellenboschvleiTapinocephalus A-Z.A relatively well-preserved fragment of skull roof, preserving the interorbital and inter-temporal regions and dorso-medial portion of the occiput.A proburnetiine burnetiamorph.
Dinocephalian
Anteosauridae
Anteosaurs of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Anteosaurus A. magnificusBeaufort West, Prince Albert, and LaingsburgTapinocephalus A-Z.Several complete skulls, dentition, and partial postcranial skeleton.A large carnivorous anteosaur. Anteosaurus magnificus BW lateral.png
Australosyodon A. nyaphuliPrince Albert and TuinkraalEodicynodon A-Z.A skull and mandible with a preserved left side.A dinocephalian.
Australosyodon DB.jpg
Styracocephalidae
Styracocephalids of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Styracocephalus S. platyrhynchusRietfontein, Prince Albert, and BoesmansrivierTapinocephalus A-Z.Complete skull consists of jaws, palate, and dentition.A dinocephalian therapsid.
Styracocephalus platyrhynchus.png
Tapinocephalidae
Tapinocephalians of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Criocephalosaurus C. vanderbyliPrince AlbertLower and Middle Tapinocephalus A-Z.A skull cap consists of the frontals, parietals, postfrontals, and one pre-frontal.A tapinocephalian. Criocephalosaurus.jpg
Keratocephalus K. molochPrince Albert, Leeu Gamka, and Buffelsvlei.Tapinocephalus A-Z.Variable skulls and postcrania.A tapinocephalian.
KeratocephalusDB.jpg
Mormosaurus M. seeleyiGouph tractTapinocephalus A-Z.A partial skull.A Tapinocephalian. Mormosaurus.jpg
Moschops M. capensisDe Cypher Farm and Hottentotsrivier.Tapinocephalus A-Z.Several skeletal specimens consist of skulls and postcranial skeletons.A subaquatic tapinocephalian. Moschops capensis.jpg
M. koupensis
M. romeri
Phocosaurus P. megischionBoesmansrivier and Vers Fontein/Jan Willem Fontein.Tapinocephalus A-Z.A partial skull.A Tapinocephalian.
Crani de focosaure (Phocosaurus megischion).jpg
Tapinocaninus T. pamelaeModderdrift farmEodicynodon A-Z.Paratypes consist of several skulls with few post-cranial skeletons.A Tapinocephalian.
Tapinocaninus pamelae head.jpg
Tapinocephalus T. atherstoneiBoesmanshoek and Prince AlbertLower, Middle, and Upper part of the Tapinocephalus A-Z.A skull and postcranial elements.A giant herbivorous Tapinocephalian. Tapinocephalus DB.jpg
Struthiocephalus S. whaitsiPrince AlbertLower to Middle Tapinocephalus A-Z.A partial skull.A Tapinocephalian. Struthiocephalus DB.jpg
Titanosuchidae
Titanosuchids of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Jonkeria J. boonstaiFarm Uitkyk, Leeu-Gamka, Groot kruidfontein, Prince Albert, and Vers Fontein.Tapinocephalus A-Z.A skull and humerus.An omnivorous titanosuchid dinocephalian. Jonkeria BW.jpg
J. ingensA complete skull.
J. haughtoniA crushed skull.
J. koupensisA complete pelvis bone.
J. parvaA femur, radius, small humerus, and tarsal.
J. rossouwiThe holotype consists of postcranial skeletons.
J. truculentaA skull and partial skeleton.
J. vanderbyliA complete skull.
Titanosuchus [55] T. feroxBeaufort West, Prince Albert, Mynhardskraal, Veldmansrivier, and Lammerskraal.Tapinocephalus A-ZFragmentary jaws and post-crania that include two left humeri, femur, and two phalanges.A carnivorous titanosuchid dinocephalian.
Titanosuchus ferox.jpg
Gorgonopsia
Gorgonopsians of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Aelurosaurus A. felinusBeaufort west.Tapinocephalus A-Z.A holotype preserved skull.A gorgonopsian.
Aelurosaurus Aelurosaurus BW.jpg
Aelurosaurus
Eriphostoma Eoarctops.jpg
Eriphostoma
A. whaitsiA holotype preserved skull.
Cerdodon C. tenuidensBeaufort west.Tapinocephalus A-Z.A holotype consists of a crushed skull.A gorgonopsid.
Eriphostoma E. microdonPrince Albert, Hottentotsrivier farm, and Mynhardtskraal.Tapinocephalus A-Z.Partial skull remains.A gorgonopsid formally named Galesuchus gracilis.
Phorcys P. dubeiDelportsrivierEodicynodon and Tapinocephalus A-Z.A partial skull from the occiput (the back face of the skull) up to the orbits, including the basicranium (the floor of the skull beneath the braincase), an eroded upper surface preserving the intact pre parietal and portions of the surrounding frontals and parietal bones, with a broken left zygomatic arch and a left palatine displaced into the left orbit,A gorgonopsid.
Therocephalia
Therocephalians of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Alopecodon A. priscusZeekoegat, Prince Albert.Tapinocephalus A-ZA crushed partial skull and lower jaws.A therocephalian.
Alopecognathus A. megalopsBeaufort West and Prince Albert.Tapinocephalus A-Z.Skull specimens.A therocephalian. Alopecognathus angusticeps DB.jpg
Eutheriodon E. vandenheeveriModderdrift, Prince Albert.Eodicynodon A-Z.A partial snout and lower jaws.A scylacosaurid therocephalian.
Glanosuchus G. macropsGioflok’s Fontein, near Van der Byl’s Iird in the GouphEodicynodon A-Z.A holotype consists of a partial skull.A scylacosaurid therocephalian.
Glanosuchus macrops Broom.jpg
Hyaenasuchus H. whaitsiRietfonteinTapinocephalus A-Z.A weathered skull.A therocephalian.
Hyaenasuchus whaitsi.jpg
Ictidosaurus I. angusticepsBeaufort WestEodicynodon and Tapinocephalus A-Z.A holotype preserved skull.A scylacosaurid therocephalian.
Pardosuchus P. whaitsiPrince AlbertTapinocephalus A-Z.Holotypes consist of preserved skulls.A pristerognathinae therocephalian formally named Lycedops scholtzi.
Specimens of Pardosuchus Specimens of Pardosuchus.jpg
Specimens of Pardosuchus
Pristerognathus P. minorBeaufort West and Prince Albert.Pristerognathus A-Z.Multiple skull specimens.A therocephalian.
P. parvus
P. vanderbyli
P. vanwyki
Scymnosaurus S. feroxPrince Albert and Vers Fontein/Jan Willem ForteinTapinocephalus A-Z.Partial skull consists of snout tip, dentition, and palate.A therocephalian therapsids.
Tamboeria T. maraisiPrince Albert and Tamboers Fontein.Tapinocephalus A-Z.A middle-sized carnivorous therocephalian
Trochosuchus T. acutusRietfontein and Prince Albert.Tapinocephalus A-Z.A fossilized skull.A Lycosuchid therocephalian.
T. intermedius
T. major

Varanopidae

Varanopids of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Anningia [56] A. megalopsPrince AlbertThe Middle of the Tapinocephalus A-Z.A partial skull.A varanopid synapsid.
Elliotsmithia longiceps Elliotsmithia longiceps.png
Elliotsmithia longiceps
Elliotsmithia E. longicepsPrince AlbertTapinocephalus A-Z.A holotype consists of a skull.A small varanopid synapsid.
Heleosaurus H. scholtziVictoria West.Tapinocephalus A-Z.A preserved skeleton.A varanopid synapsid.
Microvaranops M. parentisBeukesplaas farmTapinocephalus A-Z.A skeletal aggregation containing one grown and four immature individuals.A varanopid synapsid.

Paleoflora

Plants of the Abrahamskraal Formation
TaxaSpeciesLocalityAssemblage ZoneMaterialNotesImages
Dictyopteridium [57] D. spOnder Karoo localityCast fossil specimensA Glossopteridaceae morphotaxon
Glossopteris [57] G. spCast fossil specimensA Glossopteris morphotaxon
Lidgettonia [57] L. spCast fossil specimensA Lidgettoniaceae morphotaxon
Ottokaria [57] O. spCast fossil specimensA Glossopteris morphotaxon

Correlation

The Abrahamskraal Formation corresponds with numerous localities abroad. Currently it is considered to correlate chronostratigraphically with the Rio do Rasto Formation from the Paraná Basin in Brazil, [58] [59] the Madumabisa Mudstone Formation of Zambia, [60] the Ocher and Isheevo faunas of Russia, [61] and to the Dashankou fauna from the Xidagou Formation of China. However, correlative dating between the Xidagou Formation and the Abrahamskraal Formation remains inconsistent and needs further study.

References

  1. Day, M. O.; Rubidge, B. S. (2014-12-01). "A brief lithostratigraphic review of the Abrahamskraal and Koonap formations of the Beaufort Group, South Africa: Towards a basin-wide stratigraphic scheme for the Middle Permian Karoo". Journal of African Earth Sciences. 100: 227–242. Bibcode:2014JAfES.100..227D. doi:10.1016/j.jafrearsci.2014.07.001. ISSN   1464-343X.
  2. Merrill van der Walt; Michael Day; Bruce Rubidge; Antony K. Cooper; Inge Netterberg (2010). "A new GIS-based biozone map of the Beaufort Group (Karoo Supergroup), South Africa". Palaeontologia Africana. 45: 1–6. Retrieved 2018-11-27.
  3. Cole, D.I.; Johnson, M.R.; Day, M.O. (2016-06-01). "Lithostratigraphy of the Abrahamskraal Formation (Karoo Supergroup), South Africa". South African Journal of Geology. 119 (2): 415–424. Bibcode:2016SAJG..119..415C. doi:10.2113/gssajg.119.2.415. ISSN   1012-0750.
  4. Smith, R. M. H.; Eriksson, P. G.; Botha, W. J. (1993-01-01). "A review of the stratigraphy and sedimentary environments of the Karoo-aged basins of Southern Africa". Journal of African Earth Sciences (and the Middle East). 16 (1–2): 143–169. Bibcode:1993JAfES..16..143S. doi:10.1016/0899-5362(93)90164-L. ISSN   0899-5362.
  5. Catuneanu, Octavian; Bowker, Duncan (2001-01-01). "Sequence stratigraphy of the Koonap and Middleton fluvial formations in the Karoo foredeep South Africa". Journal of African Earth Sciences. 33 (3–4): 579–595. Bibcode:2001JAfES..33..579C. doi:10.1016/S0899-5362(01)00095-1. ISSN   1464-343X.
  6. Rubidge, B. S. (ed.) 1995b. Biostratigraphy of the Beaufort Group (Karoo Supergroup). South African Committee of Stratigraphy. Biostratigraphic Series 1. Pretoria, Council for Geoscience.
  7. Cole, D.I.; Johnson, M.R.; Day, M.O. (2016-06-01). "Lithostratigraphy of the Abrahamskraal Formation (Karoo Supergroup), South Africa". South African Journal of Geology. 119 (2): 415–424. Bibcode:2016SAJG..119..415C. doi:10.2113/gssajg.119.2.415. ISSN   1012-0750.
  8. Kitching, J. W. (1970). A short review of the Beaufort zoning in South Africa. In Second Gondwana Symposium Proceedings and Papers (Vol. 1, pp. 309-312).
  9. Keyser, A.W. and Smith, R.M.H., 1978. Vertebrate biozonation of the Beaufort Group with special reference to the western Karoo Basin. Geological Survey, Department of Mineral And Energy Affairs, Republic of South Africa.
  10. Jirah, Sifelani; Rubidge, Bruce S. (2014-12-01). "Refined stratigraphy of the Middle Permian Abrahamskraal Formation (Beaufort Group) in the southern Karoo Basin". Journal of African Earth Sciences. 100: 121–135. Bibcode:2014JAfES.100..121J. doi:10.1016/j.jafrearsci.2014.06.014. ISSN   1464-343X.
  11. Catuneanu, O.; Hancox, P.J.; Rubidge, B.S. (1998-12-01). "Reciprocal flexural behaviour and contrasting stratigraphies: a new basin development model for the Karoo retroarc foreland system, South Africa" . Basin Research. 10 (4): 417. Bibcode:1998BasR...10..417C. doi:10.1046/j.1365-2117.1998.00078.x. ISSN   1365-2117. S2CID   56420970.
  12. Catuneanua, O.; Hancox, P. J.; Cairncross, B.; Rubidge, B. S. (2002-11-01). "Foredeep submarine fans and forebulge deltas: orogenic off-loading in the underfilled Karoo Basin". Journal of African Earth Sciences. 35 (4): 489–502. Bibcode:2002JAfES..35..489C. doi:10.1016/S0899-5362(02)00154-9. ISSN   1464-343X.
  13. Catuneanu, Octavian (2004). "Basement control on flexural profiles and the distribution of foreland facies: The Dwyka Group of the Karoo Basin, South Africa". Geology. 32 (6): 517. Bibcode:2004Geo....32..517C. doi:10.1130/G20526.1. ISSN   0091-7613.
  14. Clevis, Quintijn; De Boer, Poppe L.; Nijman, Wouter (2004-06-30). "Differentiating the effect of episodic tectonism and eustatic sea-level fluctuations in foreland basins filled by alluvial fans and axial deltaic systems: insights from a three-dimensional stratigraphic forward model". Sedimentology. 51 (4): 809–835. Bibcode:2004Sedim..51..809C. doi: 10.1111/j.1365-3091.2004.00652.x . ISSN   0037-0746. S2CID   128782169.
  15. Seeley, H.G. (1892). "Researches on the structure, organization, and classification of the fossil Reptilia. VII. Further observations on Pareiasaurus". Philosophical Transactions of the Royal Society of London B. 183: 311–370. doi: 10.1098/rstb.1892.0008 .
  16. Broom, R (1906). "V.—On the Permian and Triassic Faunas of South Africa". Geological Magazine. 3 (1): 29–30. Bibcode:1906GeoM....3...29B. doi:10.1017/s001675680012271x. S2CID   129265956.
  17. Watson, D.M.S. (1914). "II.—The Zones of the Beaufort Beds of the Karroo System in South Africa". Geological Magazine. 1 (5): 203–208. Bibcode:1914GeoM....1..203W. doi:10.1017/s001675680019675x. S2CID   130747924.
  18. Cisneros, Juan Carlos; Abdala, Fernando; Jashashvili, Tea; Bueno, Ana de Oliveira; Dentzien-Dias, Paula (2015-07-01). "Tiarajudens eccentricus and Anomocephalus africanus, two bizarre anomodonts (Synapsida, Therapsida) with dental occlusion from the Permian of Gondwana". Royal Society Open Science. 2 (7): 150090. Bibcode:2015RSOS....250090C. doi:10.1098/rsos.150090. ISSN   2054-5703. PMC   4632579 . PMID   26587266.
  19. Kammerer, Christian F. (2013-09-21), "A Redescription of Eriphostoma microdon Broom, 1911 (Therapsida, Gorgonopsia) from the Tapinocephalus Assemblage Zone of South Africa and a Review of Middle Permian Gorgonopsians", Early Evolutionary History of the Synapsida, Vertebrate Paleobiology and Paleoanthropology, Springer Netherlands, pp. 171–184, doi:10.1007/978-94-007-6841-3_11, ISBN   9789400768406
  20. Kammerer, Christian F.; Smith, Roger M. H.; Day, Michael O.; Rubidge, Bruce S. (2015-02-16). "New information on the morphology and stratigraphic range of the mid-Permian gorgonopsianEriphostoma microdonBroom, 1911". Papers in Palaeontology. 1 (2): 201–221. Bibcode:2015PPal....1..201K. doi:10.1002/spp2.1012. ISSN   2056-2802. S2CID   128762256.
  21. Bain, A.G. (1845). "On the discovery of the fossil remains of bidental and other reptiles in South Africa". Quarterly Journal of the Geological Society. 1 (1): 317–318. doi:10.1144/gsl.jgs.1845.001.01.72. S2CID   128602890.
  22. Cluver, M.A., 1975. A New Didynodont Reptile from the Tapinocephalus Zone [Karoo System, Beaufort Series] of South Africa, with Evidence of the Jaw Adductor Musculature.
  23. Cluver, Michael A. (1983). "reassessment of the relationships of Permian Dicynodontia (Reptilia, Therapsida) and a new classification of dicynodonts". AGRIS: International Information System for the Agricultural Science and Technology. ISBN   9780868130439.
  24. Boonstra, L. D. (1934). "A contribution to the morphology of the mammal-like reptiles of the sub-order Therocephalia". Annals of the South African Museum. 31: 215–267.
  25. Broom, R (1935). "On some new genera and species of Karroo fossil reptiles". Annals of the Transvaal Museum. 18: 55–72.
  26. Boonstra, L. D. 1948. Anomodont reptiles from the Tapinocephalus zone of the Karroo System. In: Du Toit, A. L. (ed.) Special Publications of the Royal Society of South Africa. Robert Broom Commemorative Volume., 57-64. Cape Town: The Royal Society.
  27. Broom, R (1948). "A contribution to our knowledge of the vertebrates of the Karroo Beds of South Africa". Transactions of the Royal Society of Edinburgh. 61 (2): 577–629. doi:10.1017/s0080456800004865. S2CID   131663553.
  28. Cluver, M. A. (1975). "A new dicynodont reptile from the Tapinocephalus Zone (Karoo System, Beaufort series) of South Africa, with evidence of the jaw adductor musculature". Annals of the South African Museum. 67: 7–23.
  29. Rubidge, B.S.; King, G.M.; Hancox, P.J. "The postcranial skeleton of the earliest dicynodont synapsid Eodicynodon from the Upper Permian of South Africa". Palaeontology. 37 (2): 397–408. Retrieved 2018-11-27.
  30. Cisneros, Juan Carlos; Rubidge, Bruce S.; Mason, Richard; Dube, Charlton (2008-01-01). "Analysis of millerettid parareptile relationships in the light of new material ofBroomia perplexaWatson, 1914, from the Permian of South Africa". Journal of Systematic Palaeontology. 6 (4): 453–462. Bibcode:2008JSPal...6..453C. doi:10.1017/s147720190800254x. ISSN   1477-2019. S2CID   73723455.
  31. Angielczyk, Kenneth D.; Rubidge, Bruce S.; Day, Michael O.; Lin, Florence (2016-02-06). "A reevaluation ofBrachyprosopus broomiandChelydontops altidentalis, dicynodonts (Therapsida, Anomodontia) from the middle PermianTapinocephalusAssemblage Zone of the Karoo Basin, South Africa". Journal of Vertebrate Paleontology. 36 (2): e1078342. Bibcode:2016JVPal..36E8342A. doi:10.1080/02724634.2016.1078342. ISSN   0272-4634. S2CID   130520407.
  32. Lyson, Tyler R.; Bever, Gabe S.; Scheyer, Torsten M.; Hsiang, Allison Y.; Gauthier, Jacques A. (2013-06-17). "Evolutionary Origin of the Turtle Shell". Current Biology. 23 (12): 1113–1119. Bibcode:2013CBio...23.1113L. doi: 10.1016/j.cub.2013.05.003 . ISSN   0960-9822. PMID   23727095.
  33. "A NEW GENUS OF PRIMITIVE DINOCEPHALIAN─THE THIRD REPORT ON LATE PERMIAN DASHANKOU LOWER TETRAPOD FAUNA--《VERTEBRATA PALASIATICA》1997年01期". en.cnki.com.cn. Retrieved 2018-11-27.
  34. ANGIELCZYK, KENNETH D.; RUBIDGE, BRUCE S. (2010-09-01). "A new pylaecephalid dicynodont (Therapsida, Anomodontia) from theTapinocephalusAssemblage Zone, Karoo Basin, Middle Permian of South Africa". Journal of Vertebrate Paleontology. 30 (5): 1396–1409. Bibcode:2010JVPal..30.1396A. doi:10.1080/02724634.2010.501447. ISSN   0272-4634. S2CID   129846697.
  35. Boos, A. D. S.; Kammerer, C. F.; Schultz, C. L.; Paes Neto, V. D. (2015-11-01). "A tapinocephalid dinocephalian (Synapsida, Therapsida) from the Rio do Rasto Formation (Paraná Basin, Brazil): Taxonomic, ontogenetic and biostratigraphic considerations". Journal of South American Earth Sciences. 63: 375–384. Bibcode:2015JSAES..63..375B. doi:10.1016/j.jsames.2015.09.003. ISSN   0895-9811.
  36. Boonstra, L.D., 1969. The fauna of the Tapinocephalus Zone (Beaufort beds of the Karoo)
  37. Atayman, S., Rubidge, B.S. and Abdala, F., 2009. Taxonomic re-evaluation of tapinocephalid dinocephalians. Palaeontologia africana, 44, p.88Á90. Link: https://core.ac.uk/download/pdf/39675877.pdf#page=88
  38. Lucas, S.G., 2001. A global hiatus in the Middle Permian tetrapod fossil record. Permophiles, 38, pp.24-27. Link: http://www.nigpas.ac.cn/qt/tethys_en/edit/UploadFile/200568142141602.pdf#page=26
  39. Day, Michael O.; Ramezani, Jahandar; Bowring, Samuel A.; Sadler, Peter M.; Erwin, Douglas H.; Abdala, Fernando; Rubidge, Bruce S. (2015-07-22). "When and how did the terrestrial mid-Permian mass extinction occur? Evidence from the tetrapod record of the Karoo Basin, South Africa". Proc. R. Soc. B. 282 (1811): 20150834. doi:10.1098/rspb.2015.0834. ISSN   0962-8452. PMC   4528552 . PMID   26156768.
  40. Bond, D.P.G.; Wignall, P.B.; Wang, W.; Izon, G.; Jiang, H.-S.; Lai, X.-L.; Sun, Y.-D.; Newton, R.J.; Shao, L.-Y.; Védrine, S.; Cope, H. (2010-06-01). "The mid-Capitanian (Middle Permian) mass extinction and carbon isotope record of South China". Palaeogeography, Palaeoclimatology, Palaeoecology. 292 (1–2): 282–294. Bibcode:2010PPP...292..282B. doi:10.1016/j.palaeo.2010.03.056. ISSN   0031-0182.
  41. Reisz, Robert R.; Dilkes, David W.; Berman, David S. (1998-09-15). "Anatomy and relationships ofElliotsmithia longicepsBroom, a small synapsid (Eupelycosauria: Varanopseidae) from the late Permian of South Africa". Journal of Vertebrate Paleontology. 18 (3): 602–611. Bibcode:1998JVPal..18..602R. doi:10.1080/02724634.1998.10011087. ISSN   0272-4634.
  42. MODESTO, SEAN; SIDOR, CHRISTIAN A.; RUBIDGE, BRUCE S.; WELMAN, JOHANN (2007-01-02). "A second varanopseid skull from the Upper Permian of South Africa: implications for Late Permian 'pelycosaur' evolution". Lethaia. 34 (4): 249–259. doi:10.1111/j.1502-3931.2001.tb00053.x. ISSN   0024-1164.
  43. Botha-Brink, Jennifer; Modesto, Sean P. (2007-11-22). "A mixed-age classed 'pelycosaur' aggregation from South Africa: earliest evidence of parental care in amniotes?". Proceedings of the Royal Society of London B: Biological Sciences. 274 (1627): 2829–2834. doi:10.1098/rspb.2007.0803. ISSN   0962-8452. PMC   2288685 . PMID   17848370.
  44. Cluver, M.A. and Hotton, N., 1981. The genera Dicynodon and Diictodon and their bearing on the classification of the Dicynodontia (Reptilia, Therapsida). South African Museum.
  45. Ray, Sanghamitra; Chinsamy, Anusuya (2004-03-25). "Diictodon feliceps(Therapsida, Dicynodontia): bone histology, growth, and biomechanics". Journal of Vertebrate Paleontology. 24 (1): 180–194. Bibcode:2004JVPal..24..180R. doi:10.1671/1914-14. ISSN   0272-4634. S2CID   86189707.
  46. Angielczyk, Kenneth D.; Sullivan, Corwin (2008-09-12). "Diictodon feliceps(Owen, 1876), a dicynodont (Therapsida, Anomodontia) species with a Pangaean distribution". Journal of Vertebrate Paleontology. 28 (3): 788–802. doi:10.1671/0272-4634(2008)28[788:dfoadt]2.0.co;2. ISSN   0272-4634. S2CID   85770120.
  47. Benton, M. J. (2012-03-02). "No gap in the Middle Permian record of terrestrial vertebrates". Geology. 40 (4): 339–342. Bibcode:2012Geo....40..339B. doi:10.1130/G32669.1. ISSN   0091-7613.
  48. Damiani, R. J. (2004-01-01). "Temnospondyls from the Beaufort Group (Karoo Basin) of South Africa and Their Biostratigraphy". Gondwana Research. 7 (1): 165–173. Bibcode:2004GondR...7..165D. doi:10.1016/S1342-937X(05)70315-4. ISSN   1342-937X.
  49. "Biostratigraphy of the Tapinocephalus Assemblage Zone (Beaufort Group, Karoo Supergroup), South Africa". Geoscienceworld. Retrieved 11 September 2022.
  50. Marsicano, Claudia & Latimer, Elizabeth & Rubidge, Bruce & Smith, Roger. (2017). The Rhinesuchidae and early history of the Stereospondyli (Amphibia: Temnospondyli) at the end of the Palaeozoic. Zoological Journal of the Linnean Society. 181. 10.1093/zoolinnean/zlw032.
  51. Bender, P.A. (2005). A new deep-bodied Late Permian actinopterygian fish from the Beaufort Group, South Africa.
  52. Bruce S. Rubidge, Michael O. Day, Julien Benoit, First record of the rare dicynodont Colobodectes from the southern Karoo Basin of South Africa has implications for middle Permian continental biostratigraphy, Journal of African Earth Sciences, Volume 208, 2023, 105097, ISSN 1464-343X, https://doi.org/10.1016/j.jafrearsci.2023.105097.
  53. 1 2 Duhamel, A.; Benoit, J.; Wynd, B.; Wright, A. M.; Rubidge, B. (2024). "Redescription of three basal anomodonts: a phylogenetic reassessment of the holotype of Eodicynodon oelofseni (NMQR 2913)". Frontiers in Earth Science. 11. 1220341. Bibcode:2024FrEaS..1120341D. doi: 10.3389/feart.2023.1220341 .
  54. Matlhaga, Fonda R.; Benoit, Julien; Rubidge, Bruce S. (2024). "A new middle Permian burnetiamorph (Therapsida: Biarmosuchia) from the South African Karoo filling a gap in the biarmosuchian record". Palaeontologia Africana. 58: 28–36. hdl:10539/40426.
  55. Boonstra, L. D., 1969, The fauna of the Tapinocephalus zone (Beaufort beds of the Karoo): Annals of the South African Museum, v. 56, part 1, p. 1-73.
  56. Reisz, Robert & Dilkes, David. (1992). The taxonomic position of Anningia megalops, a small amniote from the Permian of South Africa. Canadian Journal of Earth Sciences. 29. 1605-1608. 10.1139/e92-126. Anningia megalops Broom, 1927 is based upon a poorly preserved, incomplete skull and was interpreted originally as an intermediate form between therapsids and primitive nontherapsid synapsids (pelycosaurs). Restudy of the type specimen indicates that A. megalops is a nondiagnosable primitive synapsid and is, therefore, declared to be a nomen vanum.
  57. 1 2 3 4 Prevec, Rosemary & Nel, Andre & Day, Michael & Muir, Robert & Matiwane, Aviwe & Kirkaldy, Abigail & Moyo, Sydney & Staniczek, Arnold & Cariglino, Barbara & Maseko, Zolile & Kom, Nokuthula & Rubidge, Bruce & GARROUSTE, Romain & Holland, Alexandra & Barber-James, Helen. (2022). South African Lagerstätte reveals middle Permian Gondwanan lakeshore ecosystem in exquisite detail. Communications Biology. 5. 10.1038/s42003-022-04132-y.
  58. Cisneros, Juan Carlos; Abdala, Fernando; Rubidge, Bruce S.; Dentzien-Dias, Paula Camboim; Bueno, Ana de Oliveira (2011-03-25). "Dental Occlusion in a 260-Million-Year-Old Therapsid with Saber Canines from the Permian of Brazil". Science. 331 (6024): 1603–1605. Bibcode:2011Sci...331.1603C. doi:10.1126/science.1200305. ISSN   0036-8075. PMID   21436452. S2CID   8178585.
  59. Cisneros, Juan Carlos; Abdala, Fernando; Atayman-Güven, Saniye; Rubidge, Bruce S.; Şengör, A. M. Celâl; Schultz, Cesar L. (2012-01-31). "Carnivorous dinocephalian from the Middle Permian of Brazil and tetrapod dispersal in Pangaea". Proceedings of the National Academy of Sciences. 109 (5): 1584–1588. Bibcode:2012PNAS..109.1584C. doi: 10.1073/pnas.1115975109 . ISSN   0027-8424. PMC   3277192 . PMID   22307615.
  60. Sidor, Christian A.; Angielczyk, Kenneth D.; Smith, Roger M. H.; Goulding, Adam K.; Nesbitt, Sterling J.; Peecook, Brandon R.; Steyer, J. Sébastien; Tolan, Stephen (2014-06-07). "Tapinocephalids (Therapsida, Dinocephalia) from the Permian Madumabisa Mudstone Formation (Lower Karoo, Mid-Zambezi Basin) of southern Zambia". Journal of Vertebrate Paleontology. 34 (4): 980–986. Bibcode:2014JVPal..34..980S. doi:10.1080/02724634.2013.826669. ISSN   0272-4634. S2CID   128431441.
  61. Lucas, Spencer G.; Zeigler, Kate E. (2005). The Nonmarine Permian: Bulletin 30. New Mexico Museum of Natural History and Science.