Eodicynodon Assemblage Zone

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Eodicynodon Assemblage Zone
Stratigraphic range: Middle Permian
Eodicynodon BW.jpg
Eodicynodon oosthuizeni
Type Biozone
Unit of Abrahamskraal Formation of the Beaufort Group
Underlies Tapinocephalus Assemblage Zone
Overlies Ecca Group
Thicknessup to 2,034.12 feet (620 m)
Location
Region Northern & Western Cape
CountryFlag of South Africa.svg  South Africa
Extent Karoo Basin
Type section
Named for Eodicynodon
Named byHarry Govier Seeley (1892)
Robert Broom (1906, 1909)

The Eodicynodon Assemblage Zone is a tetrapod assemblage zone or biozone which correlates to the Abrahamskraal Formation, Adelaide Subgroup of the Beaufort Group, a fossiliferous and geologically important geological Group of the Karoo Supergroup in South Africa. [1] The thickest outcrops, reaching approximately 620 metres (2,030 ft), occur south-east of Sutherland, north of Prince Albert, and south-east of Beaufort West. The Eodicynodon Assemblage Zone is the lowermost biozone of the Beaufort Group. [2] [3] [4]

Contents

The name of the biozone refers to Eodicynodon oosthuizeni , a small to medium-sized herbivorous dicynodont therapsid. It is characterized by the presence of this dicynodont genus along with the Nyaphulia , and the dinocephalian Tapinocaninus pamelae . [5] [6]

History

The first fossils to be found in the Beaufort Group rocks that encompass the current eight biozones were discovered by Andrew Geddes Bain in 1856. [7] However, it was not until 1892 that it was observed that the geological strata of the Beaufort Group could be differentiated based on their fossil taxa. The initial undertaking was done by Harry Govier Seeley who subdivided the Beaufort Group into three biozones, [8] which he named (from oldest to youngest):

These proposed biozones Seeley named were subdivided further by Robert Broom between 1906 and 1909. [9] Broom proposed the following biozones (from oldest to youngest):

These biozone divisions were approved by paleontologists of the time and were left largely unchanged for several decades. [10] The rocks composing the current Eodicynodon Assemblage Zone were previously included in the upper Waterford Formation of the underlying Ecca Group. [11] This was due to prior observations of the biozone rock colours not being consistent with the known reddish to purple colours that are diagnostic of the Beaufort Group. After further stratigraphic reorganization of the Beaufort Group was conducted from the 1970s, [12] [13] [14] [15] [16] [17] it was discovered that the Eodicynodon Assemblage Zone correlated with the lower Abrahamskraal Formation, the lowermost geological formation of the Beaufort Group, and that the fossils of Eodicynodon sp. were only known from these specific rocks. [18] The Eodicynodon Assemblage Zone is currently accepted as the oldest biozone of the Beaufort Group. [19] [20] [21] [22] [23]

Lithology

The Eodicynodon Assemblage Zone correlates with the lower Abrahamskraal Formation, Adelaide Subgroup of the Beaufort Group.Outcrops of this biozone are only known from the south-western margins of the Abrahamskraal Formation and is considered to be Middle Permian (Guadalupian) in age.

The rocks of the Eodicynodon Assemblage Zone comprise mudstones, siltstones, and fine-grained, siliceous sandstone. The mudstones are olive green to moderate yellowish brown in colour and contain thinner light reddish-brown layers. The reddish-brown layers frequently contain calcareous nodules. Desiccation cracks - indicative of seasonal dry periods - and raindrop impressions are sometimes found in the mudstone layers. Argillaceous layers are also common. The siltstones are extremely fine-grained, often containing ripple marks from being deposited in low energy streams, and vary from being dark grey, greenish-grey, and blueish-grey in colour. Thin sheets of chert occur in the mudstone and less commonly in the siltstone layers. The sandstones are fine-grained and vary from being greyish olive green to dark yellowish brown. Some sandstone layers either contain or are capped by pebble-sized mudstone-clast conglomerates. These conglomerates also contain isolated fossils in some localities. The sandstones are more common and at their thickest towards the upper sections of the biozone. The rocks of this biozone were likely deposited in a subaerial deltaic environment which included floodplains. The presence of calcareous nodules also indicates that the environment was warm with seasonal dry periods. [24] [25] [26]

The depositional environment of the Eodicynodon Assemblage Zone was formed by sedimentary material being deposited in the Karoo Basin - a retro-arc foreland basin - by vast, low-energy alluvial plains flowing northwards from a southerly source area in the rising the Gondwanide mountains. The Gondwanides were the result of crustal 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 Eodicynodon Assemblage zone, and all other succeeding assemblage zones, were deposited over millions of years. [27] [28] [29]

Paleontology

The Eodicynodon Assemblage Zone is characterized by the presence of the dicynodont species Eodicynodon and the dinocephalian Tapinocaninus pamelae . [30] [31] [32] The biozone is not especially fossiliferous with the fossils of dicynodonts Eodicynodon sp . and the dinocephalians Tapinocaninus and Australosyodon nyaphuli being most commonly found. The preservation of these fossil taxa are good with the majority of fossils being found in the mudstone layers. This is especially true of the reddish-brown mudstones containing calcareous nodules. Interestingly, dinocephalian fossils have been more commonly found in the sandstones, and fossil fragments have been found in the mudstone-clast conglomerates. [33] However, tantalizing remains of more numerous fossil species have been found to date, hinting at the true level of fossil diversity that could be discovered in the future. The fragmented material includes the scales of the fish Namaichthys digitata [34] , species of temnospondyl amphibians, [35] and skull material of gorgonopsids. [36] Rarer fossils encountered in this biozone include skull material of therocephalians, [37] various anomodonts such as Patranomodon nyaphulii , [38] [39] [40] trace fossils of planolites and arthropod trackways, molluscs, and the plant remains of Glossopteris symmetrifolia , Equisetum modderdriftensis, and Schizoneura africana. [41]

The following faunal list follows Rubidge and Day 2020 [42] unless noted otherwise.

Synapsids

Temnospondyls

Fish

Mollusks

Plants

Ichnofossils

See also

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<i>Diictodon</i> Extinct genus of dicynodonts

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<span class="mw-page-title-main">Beaufort Group</span> Third of the main subdivisions of the Karoo Supergroup in South Africa

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<i>Tapinocephalus</i> Assemblage Zone

The Tapinocephalus Assemblage Zone is a tetrapod assemblage zone or biozone which correlates to the middle Abrahamskraal Formation, Adelaide Subgroup of the Beaufort Group, a fossiliferous and geologically important geological Group of the Karoo Supergroup in South Africa. The thickest outcrops, reaching approximately 2,000 metres (6,600 ft), occur from Merweville and Leeu-Gamka in its southernmost exposures, from Sutherland through to Beaufort West where outcrops start to only be found in the south-east, north of Oudshoorn and Willowmore, reaching up to areas south of Graaff-Reinet. Its northernmost exposures occur around the towns Fraserburg and Victoria West. The Tapinocephalus Assemblage Zone is the second biozone of the Beaufort Group.

<i>Cistecephalus</i> Assemblage Zone

The Cistecephalus Assemblage Zone is a tetrapod assemblage zone or biozone found in the Adelaide Subgroup of the Beaufort Group, a majorly fossiliferous and geologically important geological group of the Karoo Supergroup in South Africa. This biozone has outcrops located in the Teekloof Formation north-west of Beaufort West in the Western Cape, in the upper Middleton and lower Balfour Formations respectively from Colesberg of the Northern Cape to east of Graaff-Reinet in the Eastern Cape. The Cistecephalus Assemblage Zone is one of eight biozones found in the Beaufort Group, and is considered to be Late Permian in age.

<i>Daptocephalus</i> Assemblage Zone

The Daptocephalus Assemblage Zone is a tetrapod assemblage zone or biozone found in the Adelaide Subgroup of the Beaufort Group, a majorly fossiliferous and geologically important geological Group of the Karoo Supergroup in South Africa. This biozone has outcrops located in the upper Teekloof Formation west of 24°E, the majority of the Balfour Formation east of 24°E, and the Normandien Formation in the north. It has numerous localities which are spread out from Colesberg in the Northern Cape, Graaff-Reniet to Mthatha in the Eastern Cape, and from Bloemfontein to Harrismith in the Free State. The Daptocephalus Assemblage Zone is one of eight biozones found in the Beaufort Group and is considered Late Permian (Lopingian) in age. Its contact with the overlying Lystrosaurus Assemblage Zone marks the Permian-Triassic boundary.

<i>Lystrosaurus</i> Assemblage Zone

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<i>Cynognathus</i> Assemblage Zone Biozone which correlates to the Burgersdorp Formation of the Beaufort Group

The Cynognathus Assemblage Zone is a tetrapod biozone utilized in the Karoo Basin of South Africa. It is equivalent to the Burgersdorp Formation, the youngest lithostratigraphic formation in the Beaufort Group, which is part of the fossiliferous and geologically important Karoo Supergroup. The Cynognathus Assemblage Zone is the youngest of the eight biozones found in the Beaufort Group, and is considered to be late Early Triassic (Olenekian) to early Middle Triassic (Anisian) in age. The name of the biozone refers to Cynognathus crateronotus, a large and carnivorous cynodont therapsid which occurs throughout the entire biozone.

<i>Pristerognathus</i> Assemblage Zone

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<i>Tropidostoma</i> Assemblage Zone

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<i>Eodicynodon</i> Extinct genus of dicynodonts

Eodicynodon is an extinct genus of dicynodont therapsids, a highly diverse group of herbivorous synapsids that were widespread during the middle-late Permian and early Triassic. As its name suggests, Eodicynodon is the oldest and most primitive dicynodont yet identified, ranging from the middle to late Permian and possessing a mix of ancestral Anomodont/therapsid features and derived dicynodont synapomorphies.

<i>Tapinocaninus</i> Extinct genus of therapsids

Tapinocaninus is an extinct genus of therapsids in the family Tapinocephalidae, of which it is the most basal member. Only one species is known, Tapinocaninus pamelae. The species is named in honor of Rubidge's mother, Pam. Fossils have been found dating from the Middle Permian.

<i>Tropidostoma</i> Extinct genus of dicynodonts

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<span class="mw-page-title-main">Abrahamskraal Formation</span> Geological formation of the Beaufort Group in South Africa

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.

<span class="mw-page-title-main">Balfour Formation</span> Geological formation in the Beaufort Group of South Africa

The Balfour Formation is a geological formation that is found in the Beaufort Group, a major geological group that forms part of the greater Karoo Supergroup in South Africa. The Balfour Formation is the uppermost formation of the Adelaide Subgroup which contains all the Late Permian-aged biozones of the Beaufort Group. Outcrops and exposures of the Balfour Formation are found from east of 24 degrees in the highest mountainous escarpments between Beaufort West and Fraserburg, but most notably in the Winterberg and Sneeuberg mountain ranges near Cradock, the Baviaanskloof river valley, Graaff-Reniet and Nieu Bethesda in the Eastern Cape, and in the southern Free State province.

<span class="mw-page-title-main">Katberg Formation</span> Geological formation in the Beaufort Group of the Karoo Supergroup in South Africa

The Katberg Formation is a geological formation that is found in the Beaufort Group, a major geological group that forms part of the greater Karoo Supergroup in South Africa. The Katberg Formation is the lowermost geological formation of the Tarkastad Subgroup which contains the Lower to Middle Triassic-aged rocks of the Beaufort Group. Outcrops and exposures of the Katberg Formation are found east of 24 degrees on wards and north of Graaff-Reniet, Nieu Bethesda, Cradock, Fort Beaufort, Queensdown, and East London in the south, and ranges as far north as Harrismith in deposits that form a ring around the Drakensberg mountain ranges.

<span class="mw-page-title-main">Middleton Formation</span> Late middle Permian geological formation in the Eastern Cape

The Middleton Formation is a geological formation that extends through the Northern Cape, Western Cape, and Eastern Cape provinces of South Africa. It overlies the lower Abrahamskraal Formation, and is the eastern correlate, East of 24ºE, of the Teekloof Formation. Outcrops and exposures of the Middleton Formation range from Graaff-Reinet in the Eastern Cape onwards. The Middleton Formation's type locality lies near the small hamlet, Middleton, approximately 25 km south of Cookhouse. Other exposures lie in hillsides along the Great Fish River in the Eastern Cape. The Middleton Formation forms part of the Adelaide Subgroup of the Beaufort Group, which itself forms part of the Karoo Supergroup.

<span class="mw-page-title-main">Teekloof Formation</span> Late Permian geological formation that forms part of the Beaufort Group of South Africa

The Teekloof Formation is a geological formation that forms part of the Beaufort Group, one of the five geological groups that comprises the Karoo Supergroup in South Africa. The Teekloof Formation is the uppermost formation of Adelaide Subgroup deposits West of 24ºE and contains Middle to Late Permian-aged deposits and four biozones of the Beaufort Group. It overlies the Abrahamskraal Formation. The Teekloof Formation does not underlie other units other than the younger Karoo dolerites and sills that relate to the emplacement of the Early Jurassic Drakensberg Group to the east. Outcrops and exposures of the Teekloof Formation range from Sutherland through the mountain escarpments between Fraserburg and Beaufort West. The northernmost localities of the Teekloof Formation are found by Loxton, Victoria West and Richmond.

Phorcys is an extinct genus of gorgonopsian that lived during the Middle Permian period (Guadalupian) of what is now South Africa. It is known from two specimens, both portions from the back of the skull, that were described and named in 2022 as a new genus and species P. dubei by Christian Kammerer and Bruce Rubidge. The generic name is from Phorcys of Greek mythology, the father of the Gorgons from which the gorgonopsians are named after, and refers to its status as one of the oldest representatives of the group in the fossil record. Phorcys was recovered from the lowest strata of the Tapinocephalus Assemblage Zone (AZ) of the Beaufort Group, making it one of the oldest known gorgonopsians in the fossil record—second only to fragmentary remains of an indeterminate gorgonopsian from the older underlying Eodicynodon Assemblage Zone.

<i>Nyaphulia</i> Extinct genus of dicynodonts

Nyaphulia is an extinct genus of dicynodont therapsid from the middle Permian of South Africa, containing only the type species N. oelofseni. The generic name is in honour of John Nyaphuli of the National Museum of Bloemfontein, who contributed extensively to South African palaeontology and discovered the holotype specimen of Nyaphulia in 1982. Nyaphulia was initially named as a second species of the basal dicynodont Eodicynodon by Professor Bruce Rubidge in 1990 as E. oelofseni, named after his mentor in palaeontology and geology Dr. Burger Oelofsen.

References

  1. ↑ Rubidge, B. S. (ed.) 1995b. Biostratigraphy of the Beaufort Group (Karoo Supergroup). South African Committee of Stratigraphy. Biostratigraphic Series 1. Pretoria, Council for Geoscience
  2. ↑ S, Rubidge, Bruce (1990). "A new vertebrate biozone at the base of the Beaufort Group, Karoo sequence (South Africa)". Palaeontologia Africana. ISSN   0078-8554.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. ↑ Cole, D.I.; Johnson, M.R.; Day, M.O. (June 2016). "Lithostratigraphy of the Abrahamskraal Formation (Karoo Supergroup), South Africa". South African Journal of Geology. 119 (2): 415–424. doi:10.2113/gssajg.119.2.415. ISSN   1012-0750.
  4. ↑ 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. doi:10.1016/j.jafrearsci.2014.06.014. ISSN   1464-343X.
  5. ↑ Rubidge, B.S.; King, G.M.; Hancox, P.J. (1994). "The posteranial skeleton of the earliest dicynodont synapsid Eodicynodon from the Upper Permian of South Africa". Palaeontology. 37 (2): 397–408.
  6. ↑ Rubidge, B.S.; Modesto, S.; Sidor, C.; Welman, J. (1999). "Eunotosaurus africanus from the Ecca-Beaufort contact in Northern Cape Province, South Africa-implications for Karoo basin development". South African Journal of Science. 95 (11/12): 553–554.
  7. ↑ Bain, Andrew Geddes (1845-02-01). "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. hdl:2027/uc1.c034667778. ISSN   0370-291X. S2CID   128602890.
  8. ↑ Seeley, H. G. (1895). "Researches on the Structure, Organization, and Classification of the Fossil Reptilia. Part IX., Section 4. On the Gomphodontia". Philosophical Transactions of the Royal Society of London B. 186: 1–57. doi: 10.1098/rstb.1895.0001 . JSTOR   91793.
  9. ↑ Broom, R. (January 1906). "V.—On the Permian and Triassic Faunas of South Africa". Geological Magazine. 3 (1): 29–30. doi:10.1017/S001675680012271X. ISSN   1469-5081. S2CID   129265956.
  10. ↑ Watson, D. M. S. (May 1914). "II.—The Zones of the Beaufort Beds of the Karroo System in South Africa". Geological Magazine. 1 (5): 203–208. doi:10.1017/S001675680019675X. ISSN   1469-5081. S2CID   130747924.
  11. ↑ S, Rubidge, Bruce (1990). "A new vertebrate biozone at the base of the Beaufort Group, Karoo sequence (South Africa)". Palaeontologia Africana. ISSN   0078-8554.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  12. ↑ 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)
  13. ↑ "Inside front cover". South African Journal of Science. 75 (2). 1979-02-01. ISSN   0038-2353.
  14. ↑ 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.
  15. ↑ Keyser, A.W. (1979). "A review of the biostratigraphy of the Beaufort Group in the Karoo Basin of South Africa". Geocongress, Geological Society of South Africa. 2: 13–31.
  16. ↑ Kitching, J.W. (1984). "A reassessment of the biozonation of the Beaufort Group". Paleo News. 4 (1): 12–13.
  17. ↑ Hancox, P.J; Rubidge, B.S (2001-01-01). "Breakthroughs in the biodiversity, biogeography, biostratigraphy, and basin analysis of the Beaufort group". Journal of African Earth Sciences. 33 (3–4): 563–577. doi:10.1016/S0899-5362(01)00081-1. ISSN   1464-343X.
  18. ↑ S, Rubidge, Bruce (1990). "A new vertebrate biozone at the base of the Beaufort Group, Karoo sequence (South Africa)". Palaeontologia Africana. ISSN   0078-8554.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  19. ↑ Rubidge, B. S. (ed.) 1995b. Biostratigraphy of the Beaufort Group (Karoo Supergroup). South African Committee of Stratigraphy. Biostratigraphic Series 1. Pretoria, Council for Geoscience.
  20. ↑ van der Walt, M., Day, M., Rubidge, B., Cooper, A.K. and Netterberg, I., 2010. A new GIS-based biozone map of the Beaufort Group (Karoo Supergroup), South Africa.
  21. ↑ Day, Michael Oliver; Rubidge, Bruce Sidney (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. doi:10.1016/j.jafrearsci.2014.07.001. ISSN   1464-343X.
  22. ↑ Oliver, Day, Michael (2014-03-04). "Middle Permian continental biodiversity changes as reflected in the Beaufort Group of South Africa: a bio-and lithostratigraphic review of the Eodicynodon, Tapinocephalus and Pristerognathus assemblage zones".{{cite journal}}: Cite journal requires |journal= (help)CS1 maint: multiple names: authors list (link)
  23. ↑ Cole, D.I.; Johnson, M.R.; Day, M.O. (June 2016). "Lithostratigraphy of the Abrahamskraal Formation (Karoo Supergroup), South Africa". South African Journal of Geology. 119 (2): 415–424. doi:10.2113/gssajg.119.2.415. ISSN   1012-0750.
  24. ↑ Rubidge, B. S. (ed.) 1995b. Biostratigraphy of the Beaufort Group (Karoo Supergroup). South African Committee of Stratigraphy. Biostratigraphic Series 1. Pretoria, Council for Geoscience.
  25. ↑ S, Rubidge, Bruce (1990). "A new vertebrate biozone at the base of the Beaufort Group, Karoo sequence (South Africa)". Palaeontologia Africana. ISSN   0078-8554.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  26. ↑ Cole, D.I.; Johnson, M.R.; Day, M.O. (June 2016). "Lithostratigraphy of the Abrahamskraal Formation (Karoo Supergroup), South Africa". South African Journal of Geology. 119 (2): 415–424. doi:10.2113/gssajg.119.2.415. ISSN   1012-0750.
  27. ↑ 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): 417–439. doi:10.1046/j.1365-2117.1998.00078.x. ISSN   1365-2117. S2CID   56420970.
  28. ↑ Catuneanu, O.; Wopfner, H.; Eriksson, P.G.; Cairncross, B.; Rubidge, B.S.; Smith, R.M.H.; Hancox, P.J. (2005-10-01). "The Karoo basins of south-central Africa". Journal of African Earth Sciences. 43 (1–3): 211–253. doi:10.1016/j.jafrearsci.2005.07.007. ISSN   1464-343X.
  29. ↑ Rubidge, Bruce S.; Day, Michael O.; Barbolini, Natasha; Hancox, P. John; Choiniere, Jonah N.; Bamford, Marion K.; Viglietti, Pia A.; McPhee, Blair W.; Jirah, Sifelani (2016), "Advances in Nonmarine Karoo Biostratigraphy: Significance for Understanding Basin Development", Origin and Evolution of the Cape Mountains and Karoo Basin, Springer International Publishing, pp. 141–149, doi:10.1007/978-3-319-40859-0_14, ISBN   9783319408583
  30. ↑ S, Rubidge, Bruce (1990). "A new vertebrate biozone at the base of the Beaufort Group, Karoo sequence (South Africa)". Palaeontologia Africana. ISSN   0078-8554.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  31. ↑ J., Hancox, P.; S., Rubidge, B. (1997). "The role of fossils in interpreting the development of the Karoo Basin". Palaeontologia Africana. ISSN   0078-8554.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  32. ↑ Day, Michael Oliver; Rubidge, Bruce Sidney (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. doi:10.1016/j.jafrearsci.2014.07.001. ISSN   1464-343X.
  33. ↑ Cole, D.I.; Johnson, M.R.; Day, M.O. (June 2016). "Lithostratigraphy of the Abrahamskraal Formation (Karoo Supergroup), South Africa". South African Journal of Geology. 119 (2): 415–424. doi:10.2113/gssajg.119.2.415. ISSN   1012-0750.
  34. ↑ PA, Bender (2016-09-22). "Late Permian actinopterygian (Palaeoniscid) fishes from the Lower Beaufort Group, South Africa".{{cite journal}}: Cite journal requires |journal= (help)
  35. ↑ Damiani, Ross J. (2004-01-01). "Temnospondyls from the Beaufort Group (Karoo Basin) of South Africa and Their Biostratigraphy". Gondwana Research. 7 (1): 165–173. doi:10.1016/S1342-937X(05)70315-4. ISSN   1342-937X.
  36. ↑ Hopson, James A. (1994). "Synapsid Evolution and the Radiation of Non-Eutherian Mammals". Short Courses in Paleontology. 7: 190–219. doi:10.1017/S247526300000132X. ISSN   2475-2630.
  37. ↑ ABDALA, FERNANDO; RUBIDGE, BRUCE S.; van den HEEVER, JURI (July 2008). "The Oldest Therocephalians (Therapsida, Eutheriodontia) and the Early Diversification of Therapsida". Palaeontology. 51 (4): 1011–1024. doi: 10.1111/j.1475-4983.2008.00784.x . ISSN   0031-0239.
  38. ↑ Lucas, Spencer G.; Zeigler, Kate E. (2005). The Nonmarine Permian: Bulletin 30. New Mexico Museum of Natural History and Science.
  39. ↑ Modesto, Sean; Rubidge, Bruce (2000-09-25). "A basal anomodont therapsid from the lower Beaufort Group, Upper Permian of South Africa". Journal of Vertebrate Paleontology. 20 (3): 515–521. doi:10.1671/0272-4634(2000)020[0515:abatft]2.0.co;2. ISSN   0272-4634. S2CID   131397425.
  40. ↑ 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. doi:10.1098/rsos.150090. ISSN   2054-5703. PMC   4632579 . PMID   26587266.
  41. ↑ N.F.H. (November 1984). "J. M. Anderson & H. M. Anderson 1983. Palaeoflora of Southern Africa. Molteno Formation (Triassic). Volume 1. Part 1. Introduction; Part 2, Dicroidium. ix + 227 pp. Rotterdam: A. A. Balkema. Price Dfl. 135.00, £31.40. ISBN 90 6191 283 0 (for complete set of six volumes ISBN 90 6191 282 2)". Geological Magazine. 121 (6): 659–660. doi:10.1017/s0016756800030880. ISSN   0016-7568.
  42. ↑ Rubidge, B.S.; Day, M.O. (2020). "Biostratigraphy of the Eodicynodon Assemblage Zone (Beaufort Group, Karoo Supergroup), South Africa". South African Journal of Geology. 123 (2): 141–148. doi:10.25131/sajg.123.0010. S2CID   242275064.
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