A new kannemeyeriiform dicynodont (Ufudocyclops mukanelai, gen. et sp. nov.) from Subzone C of the Cynognathus Assemblage Zone, Triassic of South Africa, with implications for biostratigraphic correlation with other African Triassic faunas

A new burnetiamorph therapsid, Isengops luangwensis, gen. et sp. nov., is described on the basis of a partial skull from the upper Madumabisa Mudstone Formation of the Luangwa Basin of northeastern Zambia. Isengops is diagnosed by reduced palatal dentition, a ridge-like palatine-pterygoid boss, a palatal exposure of the jugal that extends far anteriorly, a tall trigonal pyramid-shaped supraorbital boss, and a recess along the dorsal margin of the lateral temporal fenestra. The upper Madumabisa Mudstone Formation was deposited in a rift basin with lithofacies characterized by unchannelized flow, periods of subaerial desiccation and non-deposition, and pedogenesis, and can be biostratigraphically tied to the upper Cistecephalus Assemblage Zone of South Africa, suggesting a Wuchiapingian age. Isengops is the second burnetiamorph recognized from Zambia and is part of a tetrapod assemblage remarkably similar to others across southern Pangea during the Wuchiapingian. A revised cladistic analysis of Biarmosuchia yielded over 500 most parsimonious trees that generally reaffirm the results of previous analyses for burnetiamorphs: Lemurosaurus is basal, Lobalopex and Isengops are proximate burnetiid outgroups, and Bullacephalus, Burnetia, Mobaceras, Niuksenitia, and Pachydectes are burnetiines. Furthermore, Russian biarmosuchians are scattered throughout the tree and do not form sister taxon relationships with each other. Burnetiamorphs display a wide disparity of cranial adornments and are relatively speciose (13 species), especially when compared to the number of specimens discovered to date (∼16 specimens). As has been suggested in some other tetrapod clades (e.g., ceratopsian dinosaurs), the burnetiamorph fossil record supports an inferred macroevolutionary relationship between cranial adornment and increased speciation rate.

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Burrow casts from the Lystrosaurus-Procolophon Assemblage-zone, Karoo Sequence, South Africa

Koedoe ◽

10.4102/koedoe.v34i1.409 ◽

1991 ◽

Vol 34 (1) ◽

Cited By ~ 34

Author(s):

G.H. Groenewald

Keyword(s):

United States ◽

South Africa ◽

United States Of America ◽

The United States ◽

Climatic Conditions ◽

Desiccation Cracks ◽

Assemblage Zone

Five types of burrow casts from the Lystrosaurus- Procolophon Assemblage-zone (Palingkloof Member and Katberg Formation, Triassic, Karoo sequence. South Africa) are associated with casts of desiccation cracks and red mudstone. Vertebrate remains of Lystrosaurus sp. and Procolophon sp. indicate that these animals probably made the burrows during the Triassic. It is possible that burrowing was an adaptive advantage during periods of severe and unfavourable climatic conditions. Similar burrow casts were found in the Dicynodon-Theriognathus Assemblage-zone, suggesting a burrowing habit for fauna represented in this zone. In structure, the burrow casts resemble those of Scoyenia, Thalassinoides, Histioderma, Gyrolithes and Planolites reported from Germany, France, Asia, Ireland, Spain and the United States of America.

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Biostratigraphy of the Scalenodontoides Assemblage Zone (Stormberg Group, Karoo Supergroup), South Africa

South African Journal of Geology ◽

10.25131/sajg.123.0017 ◽

2020 ◽

Vol 123 (2) ◽

pp. 239-248 ◽

Cited By ~ 3

Author(s):

P.A. Viglietti ◽

B.W. McPhee ◽

E.M. Bordy ◽

L. Sciscio ◽

P.M. Barrett ◽

...

Keyword(s):

South Africa ◽

Qualitative And Quantitative ◽

Karoo Basin ◽

Maximum Thickness ◽

Nomen Dubium ◽

Assemblage Zone

Abstract The Scalenodontoides Assemblage Zone (SAZ) is the oldest fossil tetrapod biozone of the Stormberg Group (Karoo Supergroup) and preserves the oldest dinosaur bearing deposits in the Karoo Basin. The SAZ represents a revision of the ‘Euskelosaurus’ Range Zone, whose taxonomic basis has been undermined because ‘Euskelosaurus’ is well demonstrated to be a nomen dubium. Recent qualitative and quantitative investigations into the biostratigraphy of the Elliot and Clarens formations have resulted in the ﬁrst biostratigraphic review of all lower Elliot Formation (lEF) taxa in nearly 40 years. Thus, we replace the ‘Euskelosaurus’ Range Zone with a new biostratigraphic assemblage zone, the Scalenodontoides Assemblage Zone (SAZ). Named after the traversodontid cynodont Scalenodontoides macrodontes, which co-occurs with the sauropodomorphs Blikanasaurus cromptoni and Melanorosaurus readi. The SAZ is currently accepted to range in age between the upper Norian and Rhaetian. Our new biozone, which reaches a maximum thickness of ~200 m, is wholly contained within the lower Elliot Formation (Stormberg Group, Karoo Supergroup).

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The Daptocephalus Assemblage Zone (Lopingian), South Africa: A proposed biostratigraphy based on a new compilation of stratigraphic ranges

Journal of African Earth Sciences ◽

10.1016/j.jafrearsci.2015.10.011 ◽

2016 ◽

Vol 113 ◽

pp. 153-164 ◽

Cited By ~ 50

Author(s):

Pia A. Viglietti ◽

Roger M.H. Smith ◽

Kenneth D. Angielczyk ◽

Christian F. Kammerer ◽

Jörg Fröbisch ◽

...

Keyword(s):

South Africa ◽

Assemblage Zone ◽

Stratigraphic Ranges

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A New Pylaecephalid Dicynodont (Therapsida, Anomodontia) from the Tapinocephalus Assemblage Zone, Karoo Basin, Middle Permian of South Africa (project)

MorphoBank datasets ◽

10.7934/p488 ◽

2014 ◽

Author(s):

D Angielczyk ◽

S Rubidge

Keyword(s):

South Africa ◽

Middle Permian ◽

Karoo Basin ◽

Assemblage Zone

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Revision of the first therocephalian,TheriognathusOwen (Therapsida: Whaitsiidae), and implications for cranial ontogeny and allometry in nonmammaliaform eutheriodonts

Journal of Paleontology ◽

10.1017/jpa.2015.32 ◽

2015 ◽

Vol 89 (4) ◽

pp. 645-664 ◽

Cited By ~ 14

Author(s):

Adam K. Huttenlocker ◽

Fernando Abdala

Keyword(s):

South Africa ◽

Southern Africa ◽

Single Species ◽

Late Permian ◽

Triassic Boundary ◽

Karoo Basin ◽

Wide Range ◽

The Status ◽

Assemblage Zone ◽

Jaw Function

AbstractHistorically, the whaitsiid therocephalianTheriognathusOwen was one of the earliest described nonmammalian therapsids, its morphology helping to link phylogenetically the Paleozoic synapsids of North America and southern Africa to their mammalian successors. However, decades of taxonomic over-splitting and superficial descriptions obscured the morphologic diversity of the genus, hindering its utility as a study system for the evolution of synapsid cranial function as well as its biostratigraphic significance in the Late Permian of southern Africa. Here, we revise the status and provenance of all the known specimens ofTheriognathusfrom South Africa, Tanzania, and Zambia. We present both qualitative and quantitative support for the presence of a single morphospecies as proposed by some authors. Proportional differences in skulls that were previously ascribed to different morphotypes (‘Aneugomphius,’ ‘Notosollasia,’ ‘Moschorhynchus,’ and ‘Whaitsia’) are largely size-related and allometric trends are considered here in the context of jaw function and prey prehension. Our results suggest that the single species,Theriognathus microps, represented one of the most abundant Late Permian therocephalians in southern Africa and is consequently a potentially useful biostratigraphic marker for the upperCistecephalus-lowerDicynodonAssemblage Zone transition (i.e., late Wuchiapingian). The wide range of preserved sizes in conjunction with recent paleohistological evidence supports that individuals spent much of their lives in an actively-growing, subadult phase. LaterDicynodonAssemblage Zone records (e.g., upper Balfour Formation) are unconfirmed as the genus was likely replaced by other theriodont predators (e.g.,Moschorhinus) leading up to the Permo-Triassic boundary in the Karoo Basin of South Africa.

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Cranial morphology and phylogenetic relationships of the Middle Permian pareiasaur Embrithosaurus schwarzi from the Karoo Basin of South Africa

Zoological Journal of the Linnean Society ◽

10.1093/zoolinnean/zlz064 ◽

2019 ◽

Author(s):

Marc Johan Van den Brandt ◽

Fernando Abdala ◽

Bruce Sidney Rubidge

Keyword(s):

South Africa ◽

South African ◽

Middle Permian ◽

Cranial Morphology ◽

Karoo Basin ◽

Assemblage Zone ◽

Mandibular Teeth ◽

First Time ◽

Globally Distributed ◽

Distinct Taxon

Abstract Pareiasaurs were globally distributed, abundant, herbivorous parareptiles of the Middle to Late Permian, with the basal-most members found in the Middle Permian of South Africa. These basal taxa were particularly abundant and went extinct at the end of the Gaudalupian (Capitanian) at the top of the Tapinocephalus Assemblage Zone. Currently four taxa are recognized in this group: Bradysaurus seeleyi, B. baini, Nochelesaurus alexanderi and Embrithosaurus schwarzi, but they are all poorly understood. We here present the first detailed cranial description and updated diagnosis for Embrithosaurus schwarzi. No cranial autapomorphies were identified. However, Embrithosaurus schwarzi is a distinct taxon in this group, based on its unique dentition and using a combination of cranial features. It has nine marginal cusps on all maxillary and mandibular teeth, and wider maxillary teeth than in the co-occurring taxa, due to the marginal cusps being arranged more regularly around the crown, and the apex of the crown lacking the long, central, three-cusped trident. Our updated phylogenetic analysis recovers the four Middle Permian South African taxa as a monophyletic group for the first time, which we call Bradysauria, comprising a clade including Embrithosaurus, Bradysaurus baini and a polytomy including Nochelesaurus and Bradysaurus seeleyi.

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Biostratigraphy of the Massospondylus Assemblage Zone (Stormberg Group, Karoo Supergroup), South Africa

South African Journal of Geology ◽

10.25131/sajg.123.0018 ◽

2020 ◽

Vol 123 (2) ◽

pp. 249-262 ◽

Cited By ~ 2

Author(s):

P.A. Viglietti ◽

B.W. McPhee ◽

E.M. Bordy ◽

L. Sciscio ◽

P.M. Barrett ◽

...

Keyword(s):

South Africa ◽

Faunal Turnover ◽

Qualitative And Quantitative ◽

Karoo Basin ◽

Maximum Thickness ◽

Extinction Event ◽

Assemblage Zone ◽

Main Index ◽

Stratigraphic Interval

Abstract The Massospondylus Assemblage Zone is the youngest tetrapod biozone in the Karoo Basin (upper Stormberg Group, Karoo Supergroup) and records one of the oldest dinosaur dominated ecosystems in southern Gondwana. Recent qualitative and quantitative investigations into the biostratigraphy of the lower and upper Elliot formations (lEF, uEF) and Clarens Formation in the main Karoo Basin resulted in the ﬁrst biostratigraphic review of this stratigraphic interval in nearly four decades, allowing us to introduce a new biostratigraphic scheme, the Massospondylus Assemblage Zone (MAZ). The MAZ expands upon the Massospondylus Range Zone by including the crocodylomorph Protosuchus haughtoni and the ornithischian Lesothosaurus diagnosticus as two co-occurring index taxa alongside the main index taxon, the sauropodomorph Massospondylus carinatus. With a maximum thickness of ~320 m in the southeastern portion of the basin, our new biozone is contained within the uEF and Clarens formations (upper Stormberg Group), however, based on vertebrate ichnofossils evidence, it may potentially extend into the sedimentary units of the lowermost Drakensberg Group. We do not propose any further subdivisions, and do not consider the Tritylodon Acme Zone (TAZ) as a temporal biostratigraphic marker within the MAZ. The MAZ is currently accepted to range in age between the Hettangian and Pliensbachian, however a faunal turnover, which observes an increase in the diversity of dinosaur clades, crocodylomorph, and mammaliaform taxa in the lower uEF, could reﬂect effects of the end-Triassic extinction event (ETE).

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