Adam Yates

Museum of Central Australia · Department of Earth Sciences

We describe new specimens of the basal ornithischian dinosaur Lesothosaurus diagnosticus Galton, 1978 collected from a bonebed in the Fouriesburg district of the Free State, South Africa. The material was collected from the upper Elliot Formation (Early Jurassic) and represents the remains of at least three individuals. These individuals are larger...

The early evolution of sauropod dinosaurs remains poorly understood, with a paucity of unequivocal sauropod taxa known from the first twenty million years of the Jurassic. Recently, the Early Jurassic of South Africa has yielded an assemblage of dental and post-cranial remains displaying a more apomorphic character suite than any other similarly ag...

The Late Triassic-Early Jurassic Elliot Formation of South Africa is one of the most important geological formations worldwide for understanding the early evolution of sauropodomorph dinosaurs. However, many of the taxa currently recognized as valid within its lower strata remain either poorly understood, vaguely diagnosed, or both. The recent disc...

Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in sauri...

Fossorialism is a beneficial adaptation for brooding, predator avoidance and protection from extreme climate. The abundance of fossilised burrow casts from the Early Triassic of southern Africa is viewed as a behavioural response by many tetrapods to the harsh conditions following the Permo-Triassic mass-extinction event. However, scarcity of verte...

Animation showing the result of the 3D segmentation of both specimens within the burrow in upper lateral view. Within the burrow (BP/1/5558), the Thrinaxodon specimen (in brown; BP/1/7199) is positioned on the burrow floor with the Broomistega (in grey; BP/1/7200) alongside, but overlying the right side of the Thrinaxodon. (MOV)

Basal sauropodomorphs from the Upper Triassic Los Colorados Formation of north-western Argentina have been known for several decades but most of them are only briefly described. New postrcanial remains of Coloradisaurus brevis, the most gracile sauropodomorph from this unit, are described here and evaluated within a phylogenetic context. These mate...

The narrow transform margin of southeast Africa and its associated sedimentological and hydrodynamic setting differs to other documented continental margins. The Durban Bluff continental shelf is extremely narrow and steep (8 km wide with a gradient ranging from 2 to 8°) characterised by a wave-and oceanic current-dominated regime. Seismic Sequence...

201X. The early evolution of postcranial skeletal pneumaticity in sauropodomorph dinosaurs. Acta Palaeontologica Polonica 5X (X): xxx-xxx. doi: 10.4202/app.2010.0075 Postcranial skeletal pneumaticity (PSP) is present in a range of basal sauropodomorphs spanning the basal sauropodomorph–sauropod transition. We describe the PSP of five taxa, Plateosa...

The extensive Early Jurassic continental strata of southern Africa have yielded an exceptional record of dinosaurs that includes scores of partial to complete skeletons of the sauropodomorph Massospondylus, ranging from embryos to large adults. In 1976 an incomplete egg clutch including in ovo embryos of this dinosaur, the oldest known example in t...

Several clades of bivalve molluscs have invaded freshwaters at various times throughout Phanerozoic history. The most successful freshwater clade in the modern world is the Unionoida. Unionoids arose in the Triassic Period, sometime after the major extinction event at the End-Permian boundary and are now widely distributed across all continents exc...

A new basal sauropodomorph dinosaur, Arcusaurus pereirabdalorum, sp. nov., is named and described on the basis of a partial, disarticulated but associated skull and dispersed cranial and postcranial elements from at least two individuals. Arcusaurus is part of a distinctive local fauna from the upper Elliot Formation (Lower Jurassic) in the Senekal...

  A new species of penicillid watering pot shell, Kendrickiana coquinacola sp. nov., is described from the middle Miocene (Balcombian) Bryant Creek Formation of the Murray Basin, South Australia. The new species differs from the extant K. veitchi in its smaller size, much shorter posterior tube, fewer tubules in the anterior watering pot structure,...

  The taxonomic status of the sauropodomorph dinosaurs from the Newark Supergroup of north-eastern USA is reviewed. The inclusion of the three articulated skeletons from Wolcott’s Quarry, Manchester, Connecticut in a single species is supported. Despite claims to the contrary the Manchester skeletons can be referred to the species Anchisaurus polyz...

Aardonyx celestae gen. et sp. nov. is described from the upper Elliot Formation (Early Jurassic) of South Africa. It can be diagnosed by autapomorphies of the skull, particularly the jaws, cervical column, forearm and pes. It is found to be the sister group of a clade of obligatory quadrupedal sauropodomorphs (Melanorosaurus + Sauropoda) and thus l...

Yates, A.M., March, 2009. The oldest South Australian cowries (Gastropoda: Cypraeidae) from the Paleogene of the St Vincent Basin. Alcheringa 33, 23–31. ISSN 0311-5518. Two occurrences of cowries in the Paleogene of the St Vincent Basin are described. Two cypraeid internal moulds from the late Eocene (Aldingan) Blanche Point Formation comprise one...

A new genus and species of stereospondyl temnospondyl, Nanolania anatopretia, is described from the Early Triassic Arcadia Formation (Rewan Group) of Queensland, Australia. N. anatopretia has several character states that suggest it belongs to the group of derived trematosaurian stereospondyls that include the Rhytidosteidae and Brachyopoidea. Thes...

Yates, A.M., December, 2008. Two new cowries (Gastropoda: Cypraeidae) from the middle Miocene of South Australia. Alcheringa 32, 353–364. ISSN 0311-5518. The South Australian specimens of the cypraeids Umbilia leptorhyncha (McCoy, 1877) and Lyncina (Austrocypraea) contusa (McCoy, 1877) are re-examined. Umbilia caepa sp. nov. differs from U. leptorh...

A parsimony analysis of ‘higher’ temnospondyls (all temnospondyls descended from the common ancestor of Eryops and Parotosuchus) was performed using 37 terminal taxa and 121 osteological characters. Bremer support values for each internal node were calculated as a measure of clade strength. Additionally, the shortest trees that conformed to some al...

  Dicynodont therapsids were near-ubiquitous components of Permo-Triassic terrestrial faunas, but the morphology of many of the nominal species remains poorly understood. Here we provide a detailed redescription of the cranium of the poorly known Dolichuranus primaevus from the Middle Triassic Omingonde Formation of Namibia, based on both the holot...

The tetrapod record of the 'Stormberg Group', including the Lower Elliot Formation, in the South African Karoo is widely dominated by archosaurian reptiles, contrasting with the therapsid dominion of the subjacent Beaufort Group. The only therapsids represented by skeletal remains in the Upper Triassic Lower Elliot Formation are the large traversod...

Eucnemesaurus fortis Van Hoepen 1920 from the Late Triassic of South Africa is demonstrated to be the senior synonym of the puzzling dinosaur taxon Aliwalia rex Galton 1985. A new specimen of this poorly-known taxon is described. Eucnemesaurus is clearly a sauropodomorph and increases the diversity of sauropodomorph taxa in the South African Late T...

Numerous isolated bones from a Rhaetian (Upper Triassic) fissure fill in Clifton, Bristol, England have been referred to the basal sauropodomorph Thecodontosaurus Riley & Stutchbury, 1836 (type genus of T. antiquus Riley & Stutchbury vide Owen, 1842). T. caducus Yates, 2003 (Rhaetian or Lower Jurassic fissure fill, South Wales) is based on several...

A proximal caudal vertebra from the upper Elliot Formation (Early Jurassic) of the main Karoo Basin is identified as a sauropod dinosaur more derived than basal forms such as Antetonitrus and Blikanasaurus from the lower Elliot Formation (Late Triassic). The caudal displays an ambiguous autapomorphy with the Early-Middle Jurassic Vulcanodon from Zi...

A skull of the basal trematosauroid temnospondyl Thoosuchus yakovlevi from the Early Triassic of Russia is described. Characters showing phylogenetic affinities with the Trematosauroidea include the presence of a postorbital-prepineal growth zone, the well-developed sensory sulci, the ventrally knife-edged cultriform process of the parasphenoid, an...

The species taxonomy of the sauropodomorph dinosaurs from the Löwenstein Formation of Germany is examined. Previous work has classified these into two taxa: Sellosaurus gracilis from a number of localities and the widespread Plateosaurus engelhardti from a single monospecific accumulation in the Löwenstein Formation, near the town of Trossingen. Th...

Fossilised traces of swimming amphibians, assigned to Batrachichnus delicatulus and Serpentichnus robledoensis igen. et isp. nov., are described from the Lower Permian of the Robledo Mountains, southern New Mexico. The B. delicatulus specimen is interpreted as a trackway of a small ‘amphibian’ (temnospondyl, nectridean, microsaur or juvenile embolo...

A 251 million year old partial burrow cast containing an articulated skeleton of the mammal-like carnivore Thrinaxodon liorhinus is the oldest evidence for burrowing by a cynodont synapsid. The burrow cast comes from terrestrial flood plain sediments close to the Permian-Triassic boundary in the Karoo of South Africa. Together with those of the lat...

A partial dinosaur skeleton from the Upper Triassic (Norian) sediments of South Africa is described and named Antetonitrus ingenipes. It provides the first informative look at a basal sauropod that was beginning to show adaptations towards graviportal quadrupedalism such as an elongated forelimb, a modified femoral architecture, a shortened metatar...

Juvenile sauropodomorph specimens from a Late Triassic/Early Jurassic fissure fill in Pant‐y‐ffynnon Quarry, South Wales are redescribed and named as a new species, Thecodontosaurus caducus. T. caducus can be diagnosed by the presence of pleurocoel‐like pits on the neurocentral sutures of the sixth, seventh and eighth cervical vertebrae. It is furt...

One of the ultimate aims of systematics is the reconstruction of the tree of life. This is a huge undertaking that is inhibited by the existence of a computational limit to the inclusiveness of phylogenetic analyses. Supertree methods have been developed to overcome, or at least to go around this problem by combining smaller, partially overlapping...

A temnospondyl mandible from the Panchet Formation, described as Manubrantlia khaki, new genus and species, has several apomorphic characters that indicate it belongs to the Lapillopsidae, a taxon previously known only from the Early Triassic of Australia. The postglenoid area of the lower jaw of lapillopsids is quite similar to that of lydekkerini...

Australia has representatives of the earliest known tetrapod vertebrates from the Late Devonian and evidence that their amphibian descendants survived here at least until the Viséan. There is no record of tetrapods from later in the Carboniferous or the earlier part of the Permian, and scant remains only from the Late Permian. A single Permian reco...

New material from the Arcadia Formation (Rewan Group) of Queensland is referred to the small temnospondyl Lapillopsis nana. This species is redescribed and its systematic position is reconsidered. Originally described as a dissorophoid, L. nana lacks most of the synapomorphies that diagnose the Dissorophoidea, such as a laterally exposed palatine,...