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Martin G. Lockley - One of the best experts on this subject based on the ideXlab platform.
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tracking the pliensbachian toarcian karoo firewalkers Trackways of quadruped and biped dinosaurs and mammaliaforms
PLOS ONE, 2020Co-Authors: Emese M Bordy, Martin G. Lockley, Akhil Rampersadh, Miengah Abrahams, Howard V HeadAbstract:The Karoo igneous rocks represent one of the largest continental flood basalt events (by volume) on Earth, and are not normally associated with fossils remains. However, these Pliensbachian–Toarcian lava flows contain sandstone interbeds that are particularly common in the lower part of the volcanic succession and are occasionally fossiliferous. On a sandstone interbed in the northern main Karoo Basin, we discovered twenty-five tridactyl and tetradactyl vertebrate tracks comprising five Trackways. The tracks are preserved among desiccation cracks and low-amplitude, asymmetrical ripple marks, implying deposition in low energy, shallow, ephemeral water currents. Based on footprint lengths of 2–14 cm and Trackway patterns, the trackmakers were both bipedal and quadrupedal animals of assorted sizes with walking and running gaits. We describe the larger tridactyl tracks as “grallatorid” and attribute them to bipedal theropod dinosaurs, like Coelophysis, a genus common in the Early Jurassic of southern Africa. The smallest tracks are tentatively interpreted as Brasilichnium-like tracks, which are linked to synapsid trackmakers, a common attribution of similar tracks from the Lower to Middle Jurassic record of southern and southwestern Gondwana. The Trackway of an intermediate-sized quadruped reveals strong similarities in morphometric parameters to a post-Karoo Zimbabwean Trackway from Chewore. These Trackways are classified here as a new ichnogenus attributable to small ornithischian dinosaurs as yet without a body fossil record in southern Africa. These tracks not only suggest that dinosaurs and therapsids survived the onset of the Drakensberg volcanism, but also that theropods, ornithischians and synapsids were among the last vertebrates that inhabited the main Karoo Basin some 183 Ma ago. Although these vertebrates survived the first Karoo volcanic eruptions, their rapidly dwindling habitat was turned into a land of fire as it was covered by the outpouring lavas during one of the most dramatic geological episodes in southern Africa.
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Footprints of marine reptiles from the Middle Triassic (Anisian-Ladinian) Guanling Formation of Guizhou Province, southwestern China: The earliest evidence of synchronous style of swimming
Palaeogeography Palaeoclimatology Palaeoecology, 2020Co-Authors: Lida Xing, Hendrik Klein, Martin G. Lockley, Michael J. Benton, Rong Zeng, Anthony RomilioAbstract:Abstract Subaqueously-registered Trackways of marine tetrapods are only rarely preserved; some of the best examples so far come from the Shizishan Member (Member II) of the Guanling Formation (Middle Triassic, Anisian-Ladinian) of Yunnan Province in southwestern China. The unit is well-known for the Luoping Biota including abundant skeletons of marine reptiles. The described footprints consist of impressions of fin-like autopodia comprising numerous broad Trackways that have been named Dikoposichnus luopingensis and interpreted as having been made by foraging nothosaurs. Morphologically identical tracks and Trackways have now been discovered near the city of Anshun in Guizhou Province, in slightly older strata and on a large surface of argillaceous dolostone belonging to the Songzikan Member (Member I) of the Guanling Formation. Additionally, a second morphotype is abundant on the same surface, with long Trackways that show semi-plantigrade to plantigrade foot imprints with four distinct digit impressions. All tracks are similar in shape and positioned symmetrically, in broad Trackways on either side of the Trackway midline. Based on several unique features this morphotype is assigned here to the new ichnotaxon Anshunpes aquacursor ichnogen. nov. ichnosp. nov. It is interpreted as the Trackway of a buoyant and punting tetrapod, using its forefeet only. The trackmaker is inferred to be similar to some diapsid placodonts and saurosphargids whose skeletons have been found in the Guanling Formation (Middle Triassic, Anisian-Ladinian) and in the overlying Falang Formation (Middle–Upper Triassic, Ladinian–Carnian). Comparative measurements of Trackways and skeletons support this. Additional associated ichnofossils are enigmatic traces such as isolated large oval impressions and cord-like knobby structures. The palaeoenvironment was a shallow near-coast marine habitat, possibly a lagoon. The ichnofauna from Anshun is important, because it is the first record of subaqueous progression activity by marine diapsid placodonts and/or saurosphargids, and also indicates the early adoption of a synchronous style of swimming by marine reptiles.
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Largest Cretaceous lizard track assemblage, new morphotypes and longest Trackways comprise diverse components of an exceptional Korean Konservat-Lagerstätten ichnofauna
Scientific Reports, 2019Co-Authors: Martin G. Lockley, Laura PiñuelaAbstract:A newly discovered assemblage of lizard tracks from the Lower Cretaceous Jinju Formation (Sindong Group, Gyeongsang Basin) Korea is the largest yet reported from the Cretaceous. It consists of at least 95 tracks comprising five Trackways, including a meter-long Trackway (T1) with 50 footprints assigned to the new ichnotaxon Neosauroides innovatus ichnosp. nov. Two other Trackways (T2 and T3) are designated N. innovatus paratypes characterized by strong heteropody, relatively wide Trackways and small narrow manus tracks. These morphological characteristics distinguish Neosauroides innovatus from the previously reported lizard Trackways Sauripes hadongensis from the Hasandong Formation and Neosauroides koreaensis from the Haman Formation, both also from the Gyeongsang Basin. These three lizard track assemblages from the Korean Cretaceous constitute the entire global lizard track record for this period. The Mesozoic record of lizard tracksites is more localized than the lizard body fossil record. This limited distribution suggests bias in the track record and the fossil record more generally. However, due to deposition of fine-grained substrates, suitable for high definition track registration, the Jinju Formation is increasingly well known as an ichnological window on small tetrapod activity and based on diversity, abundance and high-quality preservation, is regarded as an exceptional Konservat-Lagerstätten.
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Korean Trackway of a hopping, mammaliform trackmaker is first from the Cretaceous of Asia
Cretaceous Research, 2017Co-Authors: Kyung Soo Kim, Lida Xing, Martin G. Lockley, Jong Deock Lim, Yeongi ChoiAbstract:Abstract A Trackway of a small hopping mammaliform trackmaker from the Jinju Formation (Lower Cretaceous) of the Jinju City area, Korea, is the first of this type reported from the Mesozoic of Asia, and globally. The animal left a narrow Trackway (∼20 mm wide) with small tetradactyl footprints averaging less than 10 mm in diameter. Only two footprints registered with each hop (mean length 41 mm) thus indicating a bipedal gait. All Trackway evidence suggests a small “mouse-like” trackmaker. Previous reports of Trackways made by hopping tetrapods from the Mesozoic are rare and presently restricted to ichnogenus Ameghinichnus isp. indet., from the Jurassic of Argentina. Ichnogenus Musaltipes from the Cenozoic of North America, is the only other ichnogenus representing a hopping mammal. The Korean specimen here named Koreasaltipes jinjuensis, is different from these aforementioned ichnogenera in digit count, digit proportion and Trackway configuration, as well as lack of tail trace. Koreasaltipes jinjuensis is from a lake shore paleoenvironment associated with nematode tracks (Cochlichnus isp.), other small tetrapod tracks attributed to avian theropods (birds), pterosaurs and crocodylomorphs, as well as larger saurischian dinosaurs.
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Wide-gauge sauropod Trackways from the Early Jurassic of Sichuan, China: oldest sauropod Trackways from Asia with special emphasis on a specimen showing a narrow turn
Swiss Journal of Geosciences, 2016Co-Authors: Lida Xing, Martin G. Lockley, Daniel Marty, Hui Dai, Masaki Matsukawa, Guangzhao Peng, Hendrik KleinAbstract:An Early Jurassic sauropod dinosaur tracksite in the Lower Jurassic Zhenzhuchong Formation at the Changhebian site in Dazu County, Sichuan, is known to have yielded the Trackway of a turning sauropod. A re-study of the site shows that all in all there are more than 100 tracks organized in at least three sauropod Trackways. The narrow turn in one of the Trackways is confirmed and analyzed in greater detail. All of the Trackways show a wide gauge similar to Brontopodus-type Trackways, but simultaneously exhibit high heteropody typical for Parabrontopodus-type Trackways. The relative length of pes digits I, II and III is difficult to determine, but is suggestive of a primitive condition where digit I is less well developed than in Brontopodus. Thus far, they are the stratigraphically oldest sauropod Trackways known from Asia being Hettangian in age. Previously, the Trackway with the narrow turn was reported as the first turning sauropod Trackway from Asia, but recently several other turning Trackways have been reported suggesting that this behaviour is more commonly found than previously assumed and is now documented from the Early Jurassic to Late Cretaceous. Most of these examples show tight turns of between ~90° and as much as 180° suggesting that despite their large size sauropods could quite easily and abruptly change their direction of movement.
Lida Xing - One of the best experts on this subject based on the ideXlab platform.
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Footprints of marine reptiles from the Middle Triassic (Anisian-Ladinian) Guanling Formation of Guizhou Province, southwestern China: The earliest evidence of synchronous style of swimming
Palaeogeography Palaeoclimatology Palaeoecology, 2020Co-Authors: Lida Xing, Hendrik Klein, Martin G. Lockley, Michael J. Benton, Rong Zeng, Anthony RomilioAbstract:Abstract Subaqueously-registered Trackways of marine tetrapods are only rarely preserved; some of the best examples so far come from the Shizishan Member (Member II) of the Guanling Formation (Middle Triassic, Anisian-Ladinian) of Yunnan Province in southwestern China. The unit is well-known for the Luoping Biota including abundant skeletons of marine reptiles. The described footprints consist of impressions of fin-like autopodia comprising numerous broad Trackways that have been named Dikoposichnus luopingensis and interpreted as having been made by foraging nothosaurs. Morphologically identical tracks and Trackways have now been discovered near the city of Anshun in Guizhou Province, in slightly older strata and on a large surface of argillaceous dolostone belonging to the Songzikan Member (Member I) of the Guanling Formation. Additionally, a second morphotype is abundant on the same surface, with long Trackways that show semi-plantigrade to plantigrade foot imprints with four distinct digit impressions. All tracks are similar in shape and positioned symmetrically, in broad Trackways on either side of the Trackway midline. Based on several unique features this morphotype is assigned here to the new ichnotaxon Anshunpes aquacursor ichnogen. nov. ichnosp. nov. It is interpreted as the Trackway of a buoyant and punting tetrapod, using its forefeet only. The trackmaker is inferred to be similar to some diapsid placodonts and saurosphargids whose skeletons have been found in the Guanling Formation (Middle Triassic, Anisian-Ladinian) and in the overlying Falang Formation (Middle–Upper Triassic, Ladinian–Carnian). Comparative measurements of Trackways and skeletons support this. Additional associated ichnofossils are enigmatic traces such as isolated large oval impressions and cord-like knobby structures. The palaeoenvironment was a shallow near-coast marine habitat, possibly a lagoon. The ichnofauna from Anshun is important, because it is the first record of subaqueous progression activity by marine diapsid placodonts and/or saurosphargids, and also indicates the early adoption of a synchronous style of swimming by marine reptiles.
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The first theropod tracks from the Middle Jurassic of Gansu, Northwest China: new and rare evidence of quadrupedal progression in theropod dinosaurs
'Springer Science and Business Media LLC', 2019Co-Authors: Li Da-qing, Lida Xing, Lockley, Martin G., Romilio Anthony, Yang Jing-tao, Li Long-fengAbstract:A new Middle Jurassic tracksite dominated by non-avian theropod footprints from the Wangjiashan Formation in Pingchuan District, Baojishan Basin, Gansu Province has yielded a unique Trackway with four consecutive manus-pes sets. Only three previous examples, all Early Jurassic in age, of theropod Trackways are known with convincing examples of manus tracks and in each case, only two tracks were recorded in association with pes tracks with metatarsal impressions and pelvic traces indicating crouching behavior. Thus, this is the first example of manus tracks registered while a theropod trackmaker was walking. This unique configuration is here designated as Grallator pingchuanensis ichnosp. nov. which shows the trackmaker forelimbs registering in a wide straddle gait, much wider than the pes Trackway width. G. pingchuanensis confirms previous reports that theropods could occasionally register tridactyl, ectaxonic manus traces. In the case of the Pingchuan Trackway, the short step indicates an animal moving at a slow speed, probably due to a soft substrate
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Korean Trackway of a hopping, mammaliform trackmaker is first from the Cretaceous of Asia
Cretaceous Research, 2017Co-Authors: Kyung Soo Kim, Lida Xing, Martin G. Lockley, Jong Deock Lim, Yeongi ChoiAbstract:Abstract A Trackway of a small hopping mammaliform trackmaker from the Jinju Formation (Lower Cretaceous) of the Jinju City area, Korea, is the first of this type reported from the Mesozoic of Asia, and globally. The animal left a narrow Trackway (∼20 mm wide) with small tetradactyl footprints averaging less than 10 mm in diameter. Only two footprints registered with each hop (mean length 41 mm) thus indicating a bipedal gait. All Trackway evidence suggests a small “mouse-like” trackmaker. Previous reports of Trackways made by hopping tetrapods from the Mesozoic are rare and presently restricted to ichnogenus Ameghinichnus isp. indet., from the Jurassic of Argentina. Ichnogenus Musaltipes from the Cenozoic of North America, is the only other ichnogenus representing a hopping mammal. The Korean specimen here named Koreasaltipes jinjuensis, is different from these aforementioned ichnogenera in digit count, digit proportion and Trackway configuration, as well as lack of tail trace. Koreasaltipes jinjuensis is from a lake shore paleoenvironment associated with nematode tracks (Cochlichnus isp.), other small tetrapod tracks attributed to avian theropods (birds), pterosaurs and crocodylomorphs, as well as larger saurischian dinosaurs.
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Wide-gauge sauropod Trackways from the Early Jurassic of Sichuan, China: oldest sauropod Trackways from Asia with special emphasis on a specimen showing a narrow turn
Swiss Journal of Geosciences, 2016Co-Authors: Lida Xing, Martin G. Lockley, Daniel Marty, Hui Dai, Masaki Matsukawa, Guangzhao Peng, Hendrik KleinAbstract:An Early Jurassic sauropod dinosaur tracksite in the Lower Jurassic Zhenzhuchong Formation at the Changhebian site in Dazu County, Sichuan, is known to have yielded the Trackway of a turning sauropod. A re-study of the site shows that all in all there are more than 100 tracks organized in at least three sauropod Trackways. The narrow turn in one of the Trackways is confirmed and analyzed in greater detail. All of the Trackways show a wide gauge similar to Brontopodus-type Trackways, but simultaneously exhibit high heteropody typical for Parabrontopodus-type Trackways. The relative length of pes digits I, II and III is difficult to determine, but is suggestive of a primitive condition where digit I is less well developed than in Brontopodus. Thus far, they are the stratigraphically oldest sauropod Trackways known from Asia being Hettangian in age. Previously, the Trackway with the narrow turn was reported as the first turning sauropod Trackway from Asia, but recently several other turning Trackways have been reported suggesting that this behaviour is more commonly found than previously assumed and is now documented from the Early Jurassic to Late Cretaceous. Most of these examples show tight turns of between ~90° and as much as 180° suggesting that despite their large size sauropods could quite easily and abruptly change their direction of movement.
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Vertebrate Ichnopathology: Pathologies Inferred from Dinosaur Tracks and Trackways from the Mesozoic
Ichnos, 2015Co-Authors: Richard T Mccrea, James O Farlow, Lida Xing, Martin G. Lockley, Lisa G. Buckley, Neffra A. Matthews, S. George Pemberton, Darren H. Tanke, Charles W. Helm, Brent H. BreithauptAbstract:Literature concerning dinosaur footprints or Trackways exhibiting abnormal gait or morphology reflecting pathology (ichnopathology) is rare. We report on a number of Jurassic and Cretaceous occurrences of theropod footprints from western North America with unusual morphologies interpreted herein as examples of inferred pathologies, or ichnopathologies. The majority of ichnopathologies are primarily manifested in the digit impressions and include examples of swelling, extreme curvature, dislocation or fracture, and amputation. A number of occurrences are single tracks on ex situ blocks with substantial deformation (inferred dislocation or fracture), or absence of a single digit impression. Two occurrences are from in situ natural mould Trackways, one of which is a lengthy Trackway of a presumed allosauroid with no noticeable deformation of the digits or feet but with strong inward rotation of the left footprint toward the midline and a pronounced, waddling limp. The other is a tyrannosaurid Trackway consis...
Hendrik Klein - One of the best experts on this subject based on the ideXlab platform.
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Footprints of marine reptiles from the Middle Triassic (Anisian-Ladinian) Guanling Formation of Guizhou Province, southwestern China: The earliest evidence of synchronous style of swimming
Palaeogeography Palaeoclimatology Palaeoecology, 2020Co-Authors: Lida Xing, Hendrik Klein, Martin G. Lockley, Michael J. Benton, Rong Zeng, Anthony RomilioAbstract:Abstract Subaqueously-registered Trackways of marine tetrapods are only rarely preserved; some of the best examples so far come from the Shizishan Member (Member II) of the Guanling Formation (Middle Triassic, Anisian-Ladinian) of Yunnan Province in southwestern China. The unit is well-known for the Luoping Biota including abundant skeletons of marine reptiles. The described footprints consist of impressions of fin-like autopodia comprising numerous broad Trackways that have been named Dikoposichnus luopingensis and interpreted as having been made by foraging nothosaurs. Morphologically identical tracks and Trackways have now been discovered near the city of Anshun in Guizhou Province, in slightly older strata and on a large surface of argillaceous dolostone belonging to the Songzikan Member (Member I) of the Guanling Formation. Additionally, a second morphotype is abundant on the same surface, with long Trackways that show semi-plantigrade to plantigrade foot imprints with four distinct digit impressions. All tracks are similar in shape and positioned symmetrically, in broad Trackways on either side of the Trackway midline. Based on several unique features this morphotype is assigned here to the new ichnotaxon Anshunpes aquacursor ichnogen. nov. ichnosp. nov. It is interpreted as the Trackway of a buoyant and punting tetrapod, using its forefeet only. The trackmaker is inferred to be similar to some diapsid placodonts and saurosphargids whose skeletons have been found in the Guanling Formation (Middle Triassic, Anisian-Ladinian) and in the overlying Falang Formation (Middle–Upper Triassic, Ladinian–Carnian). Comparative measurements of Trackways and skeletons support this. Additional associated ichnofossils are enigmatic traces such as isolated large oval impressions and cord-like knobby structures. The palaeoenvironment was a shallow near-coast marine habitat, possibly a lagoon. The ichnofauna from Anshun is important, because it is the first record of subaqueous progression activity by marine diapsid placodonts and/or saurosphargids, and also indicates the early adoption of a synchronous style of swimming by marine reptiles.
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Sauropodomorph dinosaur Trackways from the Fleming Fjord Formation of East Greenland: evidence for Late Triassic sauropods
Acta Palaeontologica Polonica, 2017Co-Authors: Jens N. Lallensack, Hendrik Klein, Jesper Milàn, Oliver Wings, Octávio Mateus, Lars B. ClemmensenAbstract:The Late Triassic (Norian–early Rhaetian) Fleming Fjord Formation of central East Greenland preserves a diverse fossil fauna, including both body and trace fossils. Trackways of large quadrupedal archosaurs, although already reported in 1994 and mentioned in subsequent publications, are here described and figured in detail for the first time, based on photogrammetric data collected during fieldwork in 2012. Two Trackways can be referred to Eosauropus, while a third, bipedal Trackway may be referred to Evazoum, both of which have been considered to represent sauropodomorph dinosaur tracks. Both the Evazoum and the Eosauropus Trackways are distinctly larger than other Trackways referred to the respective ichnogenera. The trackmaker of the best preserved Eosauropus Trackway is constrained using a synapomorphy-based approach. The quadrupedal posture, the entaxonic pes structure, and five weight-bearing digits indicate a derived sauropodiform trackmaker. Other features exhibited by the tracks, including the semi-digitigrade pes and the laterally deflected unguals, are commonly considered synapomorphies of more exclusive clades within Sauropoda. The present Trackway documents an early acquisition of a eusauropod-like pes anatomy while retaining a well-developed claw on pedal digit IV, which is reduced in eusauropods. Although unequivocal evidence for sauropod dinosaurs is no older than the Early Jurassic, the present Trackway provides evidence for a possible Triassic origin of the group
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Wide-gauge sauropod Trackways from the Early Jurassic of Sichuan, China: oldest sauropod Trackways from Asia with special emphasis on a specimen showing a narrow turn
Swiss Journal of Geosciences, 2016Co-Authors: Lida Xing, Martin G. Lockley, Daniel Marty, Hui Dai, Masaki Matsukawa, Guangzhao Peng, Hendrik KleinAbstract:An Early Jurassic sauropod dinosaur tracksite in the Lower Jurassic Zhenzhuchong Formation at the Changhebian site in Dazu County, Sichuan, is known to have yielded the Trackway of a turning sauropod. A re-study of the site shows that all in all there are more than 100 tracks organized in at least three sauropod Trackways. The narrow turn in one of the Trackways is confirmed and analyzed in greater detail. All of the Trackways show a wide gauge similar to Brontopodus-type Trackways, but simultaneously exhibit high heteropody typical for Parabrontopodus-type Trackways. The relative length of pes digits I, II and III is difficult to determine, but is suggestive of a primitive condition where digit I is less well developed than in Brontopodus. Thus far, they are the stratigraphically oldest sauropod Trackways known from Asia being Hettangian in age. Previously, the Trackway with the narrow turn was reported as the first turning sauropod Trackway from Asia, but recently several other turning Trackways have been reported suggesting that this behaviour is more commonly found than previously assumed and is now documented from the Early Jurassic to Late Cretaceous. Most of these examples show tight turns of between ~90° and as much as 180° suggesting that despite their large size sauropods could quite easily and abruptly change their direction of movement.
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the longest theropod Trackway from east asia and a diverse sauropod theropod and ornithopod track assemblage from the lower cretaceous jiaguan formation southwest china
Cretaceous Research, 2015Co-Authors: Lida Xing, Hendrik Klein, Martin G. Lockley, Daniel Marty, Guangzhao Peng, Jianping Zhang, Richard T Mccrea, Scott W PersonsAbstract:Abstract Here we report a large dinosaur tracksite from an extensive fluvial sandstone surface in the Lower Cretaceous Jiaguan Formation of Sichuan Province, China. The site contains over 250 individual tracks comprising at least 18 recognizable Trackways, including the longest theropod Trackway (cf. Eubrontes ) known from China. This exceptional theropod Trackway consists of 81 successive footprints covering a distance of 69 m. The tracks are well-preserved and are expressed both as true tracks on the main “upper” surface and as transmitted undertracks on a locally exposed “lower” bed. Also recorded are six other theropod Trackways, including small Grallator -like ichnites, eight sauropod Trackways (cf. Brontopodus ), and three small ornithopod (cf. Ornithopodichnus ) Trackways with a parallel orientation, which may indicate gregarious behavior. Several Trackways of a larger theropod trackmaker show pes imprints with elongated traces of the metatarsals, suggesting extramorphological (substrate-controlled) variation and/or plantigrade posture, which is here interpreted as indicating a change in gait assumed in response to deep and soft sediment. The assemblage indicates a diverse dinosaur fauna in the Lower Cretaceous Sichuan Basin with variously sized theropods, sauropods, and ornithopods. The late occurrence of footprints of the Grallator-Eubrontes plexus in Lower Cretaceous strata is further evidence of the extended stratigraphic range of this morphotype and the distinct palaeobiogeographic distribution of these trackmakers in East Asia.
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A new early cretaceous dinosaur track assemblage and the first definite non-avian theropod swim Trackway from China
Chinese Science Bulletin, 2013Co-Authors: Lida Xing, Hendrik Klein, Martin G. Lockley, W. Scott Persons, Jianping Zhang, Andrew R. C. Milner, Jiefang EbiAbstract:The Trackway of a swimming theropod (ichnogenus Characichnos) is reported from the Lower Cretaceous Feitianshan Formation of Sichuan, China. These swim tracks help confirm that non-avian theropods were capable of forging moderately deep bodies of water. The Trackway occurs on the same surface as a typical walking Trackway of a sauropod (ichnogenus Brontopodus). Both occurrences are the first reported from the Cretaceous of Sichuan, and the swim tracks are the first well-preserved example of a Characichnos Trackway from China. Additionally, a theropod walking Trackway and several ornithopod walking Trackways (similar to the ichnogenus Caririchnium) occur in the same horizon. The ornithopod Trackways show a parallel orientation, suggesting gregarious behavior of the trackmakers, which may have been iguanodontiforms and/or hadrosauriforms. The co-occurrence of theropod swim tracks and theropod walking tracks suggests a fluctuation of water depth within a distinct time span.
Christopher A. Racay - One of the best experts on this subject based on the ideXlab platform.
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A Long Mortichnial Trackway of Mesolimulus walchi from the Upper Jurassic Solnhofen Lithographic Limestone near Wintershof, Germany
2017Co-Authors: Dean Lomax, Christopher A. RacayAbstract:A 9.7 metre long Trackway was discovered in a plattenkalk quarry near the village of Wintershof, Bavaria; Germany in 2002. The huge ichnofossil derives from the Lower Tithonian, Upper Jurassic Solnhofen Lithographic Limestone. The Trackway is complete from beginning to end and consists of footprints, telson drag impressions and is identified as the ichnotaxon Kouphichnium isp. Preserved at the very end of the Trackway is a complete specimen of Mesolimulus walchi confirming the Trackway as a mortichnia (‘death march’). Trackways and trace makers preserved together in the fossil record are rare and such specimens allow unique insights into behaviour and ecology. The events that led to M. walchi preserved in this sediment are unknown; however a most likely scenario is that the limulid was washed into the lagoonal environment during a harsh storm.
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A Long Mortichnial Trackway of Mesolimulus walchi from the Upper Jurassic Solnhofen Lithographic Limestone near Wintershof, Germany
Ichnos, 2012Co-Authors: Dean R. Lomax, Christopher A. RacayAbstract:A 9.7 m long Trackway was discovered in a plattenkalk quarry near the village of Wintershof, Bavaria, Germany, in 2002. The huge ichnofossil derives from the Lower Tithonian, Upper Jurassic Solnhofen Lithographic Limestone. The Trackway is complete from beginning to end and consists of footprints, telson drag impressions, prosoma imprints and is identified as the ichnotaxon Kouphichnium isp. Preserved at the very end of the Trackway is a complete specimen of Mesolimulus walchi confirming the Trackway as a mortichnia (death march). Trackways and trace makers preserved together in the fossil record are rare and such specimens allow unique insights into behavior and ecology. The events that led to M. walchi preserved in this sediment are unknown; however, a most likely scenario is that the limulid was washed into the lagoonal environment during a harsh storm.
Simon J. Braddy - One of the best experts on this subject based on the ideXlab platform.
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Eurypterid Trackways from Early Devonian tidal facies of Alken an der Mosel (Rheinisches Schiefergebirge, Germany)
Palaeobiodiversity and Palaeoenvironments, 2010Co-Authors: Markus Poschmann, Simon J. BraddyAbstract:Arthropod Trackways from the Early Devonian of Alken an der Mosel are described, assigned to the ichnospecies Palmichnium pottsae and attributed to medium-sized eurypterids known from the assemblage. Ichnological and sedimentological evidence suggests that several similarly sized animals simultaneously crawled towards, or away from, the shoreline traversing the lower intertidal zone, where conditions for Trackway preservation were most favourable. Comparison with modern horseshoe crabs suggests that this synchronized behaviour may have been part of the reproductive cycle of eurypterids, supporting the previously formulated ‘mass-moult-mate’ hypothesis.
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Eurypterid Trackways from Early Devonian tidal facies of Alken an der Mosel (Rheinisches Schiefergebirge, Germany)
Palaeobiodiversity and Palaeoenvironments, 2010Co-Authors: Markus Poschmann, Simon J. BraddyAbstract:Arthropod Trackways from the Early Devonian of Alken an der Mosel are described, assigned to the ichnospecies Palmichnium pottsae and attributed to medium-sized eurypterids known from the assemblage. Ichnological and sedimentological evidence suggests that several similarly sized animals simultaneously crawled towards, or away from, the shoreline traversing the lower intertidal zone, where conditions for Trackway preservation were most favourable. Comparison with modern horseshoe crabs suggests that this synchronized behaviour may have been part of the reproductive cycle of eurypterids, supporting the previously formulated ‘mass-moult-mate’ hypothesis.
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The neoichnology of terrestrial arthropods
Palaeogeography Palaeoclimatology Palaeoecology, 2007Co-Authors: Robert B. Davis, Nicholas J. Minter, Simon J. BraddyAbstract:A comprehensive systematic neoichnological study was conducted to investigate the affect of substrate conditions on the morphology and survivorship of terrestrial arthropod Trackways. Experiments utilized five different extant arthropods, representing a range of body forms and higher taxa: discoid cockroaches (Blaberus discoidalis), emperor scorpions (Pandinus imperator), Chilean rose tarantulas (Grammostola rosea), African giant black millipedes (Archispirostreptus gigas), and common woodlice (Oniscus asellus). Trackways were produced on substrates of various grain size and moisture content, in protocols simulating subaerial and transitional subaqueous–subaerial depositional settings. The results are illustrated systematically to provide a comprehensive record of the morphological variation that can occur in arthropod Trackways under different substrate conditions. General morphological trends, of increased definition of individual tracks and loss of tracks within series, are highlighted as “dry to dampground” and “soft to firmground” surface moisture taphoseries in the subaerial and transitional subaqueous–subaerial protocols respectively. Heavier arthropods produced Trackways across a broader moisture and grain size range, whilst different arthropods can produce similar Trackways under certain conditions. Undertrack fallout was investigated using discoid cockroaches, and the resultant undertrack taphoseries mimics the surface moisture taphoseries. Previous hypotheses on the factors that influence Trackway survivorship were also investigated. Increasing concentrations of clay minerals exponentially increases the survivorship of Trackways subjected to an air current, whereas increasing surface moisture has a linear affect, and a combination of the two provides excellent conditions for Trackway survivorship. The results of this study are fundamental to the study of fossil arthropod Trackways and can be used to aid ichnotaxonomic revisions, whilst also facilitating the identification of trace fossil producers and highlighting potential biases in palaeoecological reconstructions based on trace fossils.
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Arthropod Trackways from the Early Devonian of South Wales: a functional analysis of producers and their behaviour
Geological Magazine, 2003Co-Authors: A. Smith, Simon J. Braddy, Susan B. Marriott, Derek E. G. BriggsAbstract:Abundant arthropod Trackways, assigned to Diplichnites gouldi , are described from the Lower Old Red Sandstone (Early Devonian; Lochkovian) of Pant-y-Maes quarry, Brecon Beacons, South Wales. The Trackways are preserved on bedding planes of finely laminated planar and rippled siltstones. The sedimentology of the succession indicates that these units represent bar top and marginal deposits in a braided fluvial setting. Two Trackway types are recognized (Type A and B); comparisons with contemporaneous myriapodous producers favour kampecarid and eoarthropleurid myriapods, respectively. Functional analysis of the Trackways indicates that the producers were not using the most efficient, stable, walking techniques, but instead utilized in-phase ‘swimming stroke’-like gaits. Together with their occurrence on rippled surfaces, and lateral displacement of some Trackways (attributed to currents), this indicates that they were produced sub-aqueously.
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Eurypterid Trackways from the Table Mountain Group (Ordovician) of South Africa
Journal of African Earth Sciences, 1999Co-Authors: Simon J. Braddy, John E. AlmondAbstract:Abstract Eurypterid Trackways in paralic facies of the Graafwater and Peninsula Formations, lower Table Mountain Group (Ordovician) of the Western Cape Province, South Africa, are reviewed. The ichnotaxonomy of Trackways preserved on the ‘Brandenburg slab’ from the Graafwater area is reassessed, with the recognition of two distinct forms: (1) Palmichnium capensis (Anderson, 1975), consisting of a series of four tracks, many accessory imprints and (usually) an intermittent bilobed medial impression; and (2) Petalichnus brandenburgensis isp. nov., a much narrower Trackway with nine to ten tracks per series and no medial impression. Palmichnium capensis is interpreted as the locomotory trace of an onychopterellan eurypterid (Chelicerata: Eurypterida). Petalichnus brandenbergensis is provisionally ascribed to the Trilobita. The likely walking techniques employed by onychopterellan eurypterids are assessed from the revised ichnological evidence, comparisons with extant taxa and modelling procedures; subaqueous locomotion was achieved by a series of short hops across the substrate and on land these animals were slow-moving and cumbersome, employing an ungainly, undulatory gait.
