Review of Japanese Cenozoic (Miocene–Modern) Vertebrate Tracks

One hundred and seventy three Cenozoic vertebrate track sites from Miocene to 1600 A.D have been reported in Japan. Three ichnofaunas can be recognized: a perissodactyl and artiodactyl ichnofauna in the Miocene, an artiodactyl and proboscidean ichnofauna in the Plio-Pleistocene, and human ichnofauna from about 900–800 B.C. to about 1400–1600 A.D. Track data indicate that a predominance of large vertebrates in fluvio-lacustrine environment in lowland changed from perissodactyls to proboscidean through Miocene to Plio-Pleistocene, and ancient people then occupied lowlands instead of large animals. Pes length of proboscidean tracks revealed temporal variation, and the relationship between proboscidean body sizes and tracks was observed. The Cenozoic Japanese proboscidean trackways can be distinguished on the basis of trackway width, as narrow- and wide-gauge, but the difference between of those narrow- and wide-gauge trackways probably indicates generic level differences. The Cenozoic Japanese bird tracks can be identified as four types: ?crane (Family Gruidae?), ?heron (Family Ardeidae?), ?stork (Family Ciconiidae?), and ?shorebird tracks.     

Bird and Mammal Footprints From the Tertiary of Navarre (Western Pyrenees)

A rich variety of vertebrate footprints is known from a number of Upper Eocene to Lower Miocene localities of Navarre (western Pyrenees). The sediments were deposited in a wide range of depositional environments, from marginal marine to diversified terrestrial. Abundant bird tracks have been found in the coastal deposits of the Upper Eocene Liedena Sandstone of the Yesa and Itzagaondoa areas. Ciconiiformes-like (Leptoptilostipus pyrenaicus) and Charadriiformes-like (Charadriipeda ichnospp.) footprints have been recognized. Mammal ichnites have been discovered in the Oligocene and Lower Miocene deposits of Navarre. Equoid perissodactyl ichnites similar to those of Plagiolophustipus occur in the Oligocene fluviatile rocks of the Mués Sandstone of Olexoa and the Rocaforte Sandstone near Oibar and Sada. Trackways of entelodontids (Entelodontipus) are known in fluviatile-palustrine beds of the Oligocene Mués Sandstone of Olkotz. Additionally, bird (Charadriiformes-like) tracks are known in fluviatile-palustrine floodplain deposits of the Lower Miocene Ujué Formation of Los Arcos. In the same area, the Desoio and Los Arcos outcrops have also yielded perissodactyl trackways of possible Equoidea. Trackways of rhinocerotids (?) and artiodactyls (possibly Pecoripeda) are described from the Lower Miocene (Ramblian) palustrine limestones marginal to the Lerín Formation of Kaparroso and from alluvial fan deposits of the Uncastillo-Perdón Formation of Altzorritz, respectively.     

First dinosaur tracks from the Arabian Peninsula

Background

The evolutionary history of Mesozoic terrestrial vertebrates from the Arabian Peninsula is virtually unknown. Despite vast exposures of rocky outcrops, only a handful of fossils have yet been described from the region. Here we report a multi-taxon dinosaur track assemblage near Madar village, 47 km north of Sana''a, Republic of Yemen. This represents the first dinosaur tracksite from the Arabian Peninsula, and the only multi-taxon dinosaur ichnosite in the Middle East.

Methodology/Findings

Measurements were taken directly from trackway impressions, following standard ichnological conventions. The presence of bipedal trackmakers is evidenced by a long series of pes imprints preserving smoothly rounded posterior margins, no evidence of a hallux, bluntly rounded digit tips and digital divarication angles characteristic of ornithopod dinosaurs. Nearby, eleven parallel quadrupedal trackways document a sauropod herd that included large and small individuals traveling together. Based on the morphology of manus impressions along with a narrow-gauged stance, the quadrupedal trackways were made by non-titanosauriform neosauropods. Additional isolated tracks and trackways of sauropod and ornithopod dinosaurs are preserved nearby.

Conclusions/Significance

Taken together, these discoveries present the most evocative window to date into the evolutionary history of dinosaurs of the Arabian Peninsula. Given the limited Mesozoic terrestrial record from the region, this discovery is of both temporal and geographic significance, and massive exposures of similarly-aged outcrops nearby offer great promise for future discoveries.     

Trackway Ratio: A New Look at Trackway Gauge in the Analysis of Quadrupedal Dinosaur Trackways and its Implications for Ichnotaxonomy

A new parameter, the Trackway Ratio (TR), is proposed to supplement the previously used trackway gauge to describe and quantify the relative width of trackways in dinosaur quadrupedal gaits. It is expressed as the ratio of the width of the tracks relative to the total width of the trackway (both measured perpendicular to the long axis of the trackway). The ratio may be used with either pes (PTR) or manus (MTR) tracks. The PTR range of values for wide-, medium- and narrow-gauge trackways of previous authors are provisionally suggested to be ≤35%, 36–49% and ≥50%, respectively. The application of such a ratio would permit a more consistent ichnotaxonomy to be adopted where both track morphology and trackway parameters are used to define ichnotaxa.

Determination of the TR, as well as other parameters, will be affected by track preservation quality. Recent experiments on track simulation in the laboratory have shed further light on observations made in the field concerning the value of track measurements (in particular track length and width) recorded from below the surface on which the maker was moving. Experimental track simulations in the laboratory have shown that the dimensions of transmitted tracks preserved below the surface on which the foot was impressed may vary from 65% to 135% of the true dimensions of the indenter. Two case studies are presented that quantify the errors that may be made on calculating TR and the size, gait and speed of the maker, from trackways if the preservation of the tracks are not fully understood.

It is shown that in individual trackways the PTR may vary along the length of the trackway; so that part of the trackway may be classified as wide-gauge and other parts medium-gauge. There is a relationship between variation in PTR and that of pace angulation along the length of a single trackway. An analysis of 42 trackways, principally sauropod, shows a temporal distribution that does not agree closely with previous suggestions relating to narrow- and wide-gauge trackways.     

The first record of Anomoepus tracks from the Middle Jurassic of Henan Province,Central China

Small, gracile mostly tridactyl tracks from the Middle Jurassic of Henan Province represent the first example of the ichnogenus Anomoepus from this region. They represent a growing number of reports (at least eight) of this ichnogenus from the Jurassic of China. In conjunction with Changpeipus and Eubrontes, they appear characteristic of known global footprint biochrons. Anomoepus indicates the presence of ornithischian dinosaurs that are often scarce or unknown from skeletal remains in coeval deposits. When first discovered, these tracks were informally referred to as bird tracks. This interpretation reflects convergence between small Jurassic Anomoepus and avian theropod tracks that are hitherto known only from the Cretaceous and the Cenozoic. However, most Anomoepus are larger and more robust than any hitherto known Mesozoic avian tracks.     

Theropod and Ornithischian Footprints from the Middle Jurassic Yanan Formation of Zizhou County,Shaanxi, China

New tracksites reported from the Zizhou area elucidate the nature of the Early-Middle Jurassic dinosaurian ichnofaunas in Shaanxi Province. The assemblage is composed of footprints and trackways of medium- to large-sized theropods that show similarities with both the ichnogenera Kayentapus and Eubrontes and of small bipedal ornithischians that are referred to AS Anomoepus isp. Additionally tracks of a quadruped are present and assigned to Deltapodus isp. that may be related to a stegosaurian. Anomoepus isp. is similar to the holotype of Shensipus tungchuanensis which is, although apparently lost, re-assigned here and considered to be a subjective junior synonym of Anomoepus. It is therefore placed in new combination as Anomoepus tungchuanensis comb. nov. Identical tracks have been reported from well-preserved trackways both in the Zizhou and Shenmu areas, where they also co-occur with theropod tracks (Kayentapus and Grallator) and tracks of quadrupedal ornithischians (Shenmuichnus and Deltapodus). Thus, it appears that the carbonaceous (coal-bearing) facies of the region reveal ichnofaunas with both relatively abundant saurischian (theropod) and ornithischian tracks. This is in contrast with many areas where the ichnofaunas are heavily or exclusively saurischian (theropod) dominated.     

A dinosaur ichnocoenosis from the middle jurassic of Yorkshire,UK

An assemblage of dinosaur tracks from the undersurface of a sandstone bed in the Saltwick Formation (Middle Jurassic) of Yorkshire shows a range of morphological types, preservational variants and behavioral styles. The tracks are combinations of transmitted prints and underprints and include three distinct trackways. One trackway was made by an animal walking on exposed damp sand, another was left by an animal swimming diagonally across a current and being swept down current, while the third may have been made by an animal either running or pushing off with its feet as it drifted down current. Environmental conditions that existed during the formation of the trackways varied between crevasse splay floods and exposed damp sand. The morphology of the swimming tracks is sufficiently distinctive to warrant the erection of a new ichnogenus and ichnospecies—Characichnos tridactylus. Previously described material from Kansas, Wyoming and New Mexico can be attributed to this new ichnogenus, while specimens from Germany and Utah are only provisionally referred to it. This indicates a known range from Triassic to Cretaceous.     

Middle Triassic horseshoe crab reproduction areas on intertidal flats of Europe with evidence of predation by archosaurs

A systematically excavated track site in a 243.5 Myr old Middle Triassic (Karlstadt Formation, Pelsonian, middle Anisian) intertidal carbonate mud‐flat palaeoenvironment at Bernburg (Saxony‐Anhalt, central Germany) has revealed extensive horseshoe crab trackways attributable to the Kouphichnium Nopsca, 1923 ichnogenus. The exposed track bed of a Germanic Basin‐wide spanned intertidal megatrack site is a mud‐cracked biolaminate surface on which detailed tracks have been preserved because of rapid drying and cementation as a result of high temperatures, followed by rapid covering with a protective layer of arenitic storm or tsunami sediments. The different trackway types and their orientations have allowed a tidal sequence to be reconstructed, with the initial appearance of swimming horseshoe crabs followed by half‐swimming/half‐hopping limulids under the shallowest water conditions. The Bernburg trackways, which have mapped lengths of up to 40 m, were all produced by adult animals and exhibit a variety of shapes and patterns that reflect a range of subaquatic locomotion behaviour more typical of mating than of feeding activities. The closest match to the proportions and dimensions of the horseshoe crab tracks at Bernburg is provided by the largest known Middle Triassic limulid Tachypleus gadeai, which is known from the north‐western Tethys in Spain. The horseshoe crab body fossils recognized in the German Mesozoic intertidal zones, instead, are from juveniles. The uniformly adult size indicated by the trackways therefore suggests that they may record the oldest intertidal reproductive zones of horseshoe crabs known from anywhere in the world, with the track‐makers having possibly migrated thousands of kilometres from shallow marine areas of the north‐western Tethys to reproduce in the intertidal palaeoenvironments of the Germanic Basin. Chirotherium trackways of large thecodont archosaurs also appeared on these flats where they appear to have fed on the limulids. With the tidal ebb, smaller reptiles such as Macrocnemus (Rhynchosauroides trackways) appeared on the dry intertidal flats, probably feeding on marine organisms and possibly also on horseshoe crab eggs. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 76–105.     

Saurischian (theropod–sauropod) track assemblages from the Jiaguan Formation in the Sichuan Basin,Southwest China: ichnology and indications to differential track preservation

Saurischian (theropod and sauropod) tracks and trackways from the Jiaguan Formation (Lower Cretaceous) of the Sichuan Basin are exposed as natural casts with associated undertrack or transmitted print casts. The theropod tracks (cf. Eubrontes and Grallator) were left by differently sized trackmakers. This is a further example for the occurrence of characteristic Lower Jurassic ichnotaxa in the Cretaceous that obviously had a more extended stratigraphic range in East Asia. The sauropod trackway is tentatively assigned to cf. Brontopodus based on imprint morphology and (nearly wide) gauge. The tracks, however, allow a detailed study of their formation and the taphonomic processes under different substrate conditions. Differential preservation and erosion of primary sedimentary structures, and post-burial deformation structures, give insight into a complex preservational history during a low energy phase interrupting the deposition of a sequence of thick high energy sandstones. This is the sixth report of dinosaur tracks from the Jiaguan Formation and the fifteenth report from the Lower Cretaceous of Sichuan Province. Thus, the tetrapod ichnological record in this region is rapidly becoming of major importance for our knowledge of dinosaur faunas in south-western China.     

In the Footprints of Our Ancestors: An Overview of the Hominid Track Record

Hominid footprints are particularly appealing and evocative of the living activity of our ancestors. The most famous and oldest (Late Pliocene, ca. 3.7 Ma) hominid footprints, from Laetoli in East Africa, have been attributed, with some uncertainly, to genus Homo or Australopithecus. The African track record also yields Early Pleistocene (～1.5 Ma) tracks attributable to Homo erectus. The only well-documented Middle Pleistocene tracks (age ～325,000-385,000 yrs) are reported from Italy and presumably represent a pre-Homo sapiens species.

The oldest Late Pleistocene tracks (～117,000 yrs), from southern Africa, may represent modern humans. However, the majority of Late Pleistocene sites are European, associated with caves in Romania, Greece, France and elsewhere, where hominid track preservation is often of high quality. Dates range from ～10,000 to ～62,000 BP Cavesite mammal tracks are almost exclusively those of carnivores, thus representing a distinctive underground ecology. Late Pleistocene open air sites are reported from widely scattered locations in Africa, Turkey, Tibet, Korea, Australia and even in the New World (Chile, Argentina and Mexico).

Early to Middle Holocene sites (> ～4,000 yrs BP) mainly occupy riparian, lacustrine, estuarine and littoral settings where the ichnofaunas are dominated by ungulates and shorebirds. Among these sites from England, Nicaragua, Argentina and Mexico and the United States, a few have been described in some detail. Younger Holocene sites are frequently associated with specified cultural periods (e.g., Neolithic, Bronze Age) or specific indigenous cultures, where supplemental archeological evidence may be directly associated with the footprint evidence.

At most surficial and some subterranean hominid tracksites, mammal and/or bird tracks are quite common and of use in creating a paleoecological picture of local faunas. The global distribution of human and hominid tracks is consistent with body fossil evidence and the record of archeological, cultural artifacts. However, in a few cases tracks suggest colonization of certain regions (Tibetan Plateau and the New World) earlier than previously thought. Tracks also give clues to behavior, age and health status of the trackmakers.     

Hominid Ichnotaxonomy: An Exploration of a Neglected Discipline

Although more than 60 ancient hominid track sites ranging in age from 3.7 million to less than 500 B. P. are recorded from all continents except Antarctica, no ichnotaxonomic names have ever been formally proposed for hominid tracks. There is no prohibition to the naming of fossil footprints of species that created tracks and trackways similar to those of living species. On the contrary, there is precedent for the naming of ichnotaxa corresponding to the dominant extant vertebrates classes: mammals = Mammalipedia and birds = Avipeda. The hominid track site sample includes only about a dozen sites where footprint preservation is good enough to show details of diagnostic foot morphology and typical trackway morphology. We infer that the Acahualinca Footprint Museum site in Nicaragua represents the most important ancient hominid track site that combines accessibility, a large sample of well-preserved trackways and reliable dating. For this reason, we select the Nicaraguan tracks as the type sample for the new ichnotaxon Hominipes modernus ichnogen., and ichnsp. et ichnosp. nov., which we infer to represent fully modern Homo sapiens. Our preliminary investigations of other track sites suggest that the majority also yield H. modernus. However, at many sites preservation is insufficient to make an ichnotaxonomic designation at the species level or to infer that the trackmaker was H. sapiens. Thus, at many sites including the famous Laetoli site, we apply the more general label of Hominipes isp. indet.     

Vertebrate Ichnopathology: Pathologies Inferred from Dinosaur Tracks and Trackways from the Mesozoic

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 consisting of three footprints (one right, two left) with the two left prints exhibiting repetitive ichnopathology of a partially missing Digit II impression.     

America's Most Famous Human Footprints: History,Context and First Description of Mid-Holocene Tracks from the Shores of Lake Managua,Nicaragua

Human tracks discovered in 1874 at a site named El Cauce or Acahualinca near the shores of Lake Managua, Nicaragua, are the most famous and abundant human tracks in the Americas. They represent a landmark ichnological discovery during the late 19th century that generated much debate regarding their age and origins. Reported dates for the tracks range from 2,120 to 6,500 B.P. The site, which is now situated within the limits of Nicaragua's capital city of Managua, forms the basis of the Acahualinca Tracks Museum (Huellas de Acahualinca) and has been in place since 1953. However, it is still little known and has not been systematically studied, despite being an important window into Meso-American prehistory. Two exposures of a surface of volcanic ash reveal hundreds of human tracks comprising a minimum of 12 clearly defined trackways, and a trampled zone or path representing at least three more individuals, all heading in the same northwesterly direction. Tracks of deer, opossum and at least one bird are also present. Bison tracks collected from another nearby site (El Recreo) that is no longer accessible are on display at the museum. The Acahualinca tracks are noteworthy for the exceptional quality of preservation. We herein present the first maps of the two exposures, which combine to tell a story of human and animal activity along the shores of ancient Lake Managua several thousand years ago.     

Triassic turtle tracks and the origin of turtles

Turtle (Testudines) tracks, Chelonipus torquatus, reported from the early Middle Triassic (Anisian) of Germany, and Chelonipus isp. from the late Early Triassic (Spathian) of Wyoming and Utah, are the oldest fossil evidence of turtles, but have been omitted in recent discussions of turtle origins. These tracks provide significant clues as to how early the turtle Bauplan originated. Turtle trackways are quite distinctive: the manus and pes form tracks nearly parallel to the midline and indicate an unusually wide gait in which the trackway width is nearly equal to the stride length. These tracks do not fit what would be expected to be made by Triassic Pappochelys or Odontochelys, a supposed prototurtle and an early turtle, respectively. In contrast, these tracks are consistent with what would be expected from the Triassic turtles Proganochelys and Palaeochersis. The features inferred to be present in Triassic turtle tracks support the notion that Odontochelys is a derived aquatic branch of the turtle stem lineage rather than the ancestral state of all turtles. Chelonipus also resembles the Permian track Pachypes dolomiticus, generally assigned to a pareiasaur trackmaker. These revelations highlight the need to consider all available evidence regarding turtle origins, rather than just the body fossils.     

Extant Lizard Tracks: Variation and Implications for Paleoichnology

In this study, I collected tracks and trackways from nine species of extant lizards representing all five major lizard clades. Previously, tracks from species of only two of these clades were described. Lizard tracks conventionally are regarded as having curved digit imprints that progressively increase in length from digit I to IV, with a smaller digit V directing antero-laterally. However, the zygodactylous feet of chameleons (Calumma parsonii and Furcifer pardalis), the posteriorly directed digit V in the pes of ground-dwelling geckos (Eublepharis macularius) and the rounded feet of blue-tongued skinks (Tiliqua scincoides) did not make “typical” lizard tracks, and demonstrate that even within a limited taxonomic sample there can be considerable variation in the morphologies of lizard tracks. Among the lizards examined, mode of locomotion and how the feet function have more influence on the morphology of tracks than does the phylogenetic affinities of the trackmaker. This preliminary neoichnological study increases the known variation in lizard tracks and aids in interpreting the fossil trackway record by providing comparative information that can be used to identify fossil tracks made by lizards.     

Tracking a Legend: An Early Cretaceous Sauropod Trackway from Zhaojue County,Sichuan Province,Southwestern China

Cretaceous tetrapod (dinosaur and pterosaur) tracks from Zhaojue County in Sichuan Province are locally very abundant. Large scale quarrying operations at the Sanbiluoga Copper Mine site have produced extensive exposures, and track material for detailed study. However, natural track-bearing outcrops also occur at a site in Jiefang Township. The traditions of the local Yi people, indigenous to the area, attribute such tracks to Zhigealu, a central creator hero-ancestor, who made the footprints while riding his heavenly steed through the area. Through seeing tracks exposed by quarrying the local people offered these legend-based interpretations, and reported the Jiefang site which was previously unknown to scientists from outside the area. Thus, it is important to pay attention to local legends about track makers since they may lead directly to significant fossil footprint discoveries. Thereby paleontology and ichnological research can benefit largely from archeological sciences as well as from oral narratives from the local people. The recently discovered sauropod trackway from Jiefang is an excellent example. It comprises 16 pes-manus sets arranged in a narrow-gauge pattern. A peculiarity is the combination of this feature with morphological characteristics known from typical wide-gauge Brontopodus trackways suggesting a tentative assignment to cf. Brontopodus. The discovery enlarges the distribution and diversity of Brontopodus-like trackways and their producers in the Cretaceous Sichuan Basin.     

Pterosaur Stance and Gait and the Interpretation of Trackways

The tracks ascribed to pterosaurs from the Late Jurassic limestones at Crayssac, France, must be pterosaurian because the manus prints are so far outside those of the pes, the pes print is four times longer than wide, and the manus prints appear to preserve distinct traces of a posteromedially directed wing-finger. These tracks are different in important ways from previously described Pteraichnus trackways, which have been variably considered pterosaurian, crocodilian, or indeterminate. No Pteraichnus (sensu stricto: those not from Crayssac) tracks have diagnostic features of pterosaurs and in none can a complete phalangeal or digital formula be reconstructed; however, all published Pteraichnidae tracks fulfill the criteria of poor preservation, and some have some diagnostic features of crocodile tracks. Reconstructions of pterosaurs walking in pteraichnid tracks do not fit those tracks well, but crocodiles do. In contrast, the Crayssac tracks demonstrate the erect stance and parasagittal gait previously reconstructed for pterosaurs. They also demonstrate that the footfall pattern was not as in typical reptiles (LH-RF-RH-LF), but that the manus must have been raised before the next forward step of the ipselateral foot (LH-LF-RH-RF), suggesting that the quadrupedal pattern was secondary. The metatarsus in pterosaurs was set low at the beginning of a stride, as it is in crocodilians and basal dinosaurs. The diagnosis of the Ichnofamily Pteraichnidae comprises features of possible crocodilian trackmakers, but not of possible pterosaurian trackmakers. Trackways considered for attribution to pterosaurs should show (1) manus prints up to three interpedal widths from midline of body, and always lateral to pes prints, (2) pes prints four times longer than wide at the metatarso-phalangeal joint, and (3) penultimate phalanges longest among those of the pes.     

New Data on Therangospodus oncalensis from the Berriasian Fuentesalvo Tracksite (Villar del Río,Soria, Spain): An Example of Gregarious Behaviour in Theropod Dinosaurs

Therangospodus oncalensis is a Berriasian theropod ichnotaxon from the Cameros Basin (Soria Province, Spain). We discovered new trackways assigned to this ichnotaxon during cleaning and conservation works at the type locality (Fuentesalvo), enabling us to describe it more precisely. Therangospodus oncalensis was made by a medium-sized theropod dinosaur and is characterized by a single tapering pad on each toe, a rounded heel impression and a narrow trackway. In addition to having similar morphometric characteristics, most of the trackways at the Fuentesalvo site show comparable size and biometric features. This indicates that, in terms of size and age, a homogeneous population of a single theropod species could have produced these tracks. Moreover, the similar orientation (lying within a range of only 15°) and estimated speed suggested by most of the trackways, lend weight to the hypothesis that the trackmaker of Therangospodus oncalensis was able, at least at times, to move in structured packs displaying gregarious behaviour. Furthermore, this is the first structured pack of theropods to be described.     

Preliminary Report on the Courtedoux Dinosaur Tracksite from the Kimmeridgian of Switzerland

In 2002 a new dinosaur tracksite was discovered in calcareous laminites of early Late Kimmeridgian age along the future course of the “Transjurane” highway in Courtedoux, Canton Jura, Northern Switzerland. The site has an extraordinary scientific potential, as the laminites, which have been deposited in an intertidal to supratidal environment, contain at least 6 track-bearing levels in a total thickness of about 1 m. The laminites are being systematically excavated by the “Section de paleontologie” over an area of approximately 1500 m². So far the main track level has been uncovered over an area of about 650 m², which reveals 2 trackways of theropods and 17 trackways of sauropods. The sauropod tracks are the smallest known in the Kimmeridgian so far, and the trackways belong to the ichnogenus Parabrontopodus, which has been revealed for the first time in Switzerland. The tracksite belongs to the “Middle Kimmeridgian megatracksite” sensu Meyer (2000), and represents the most important dinosaur tracksite in Switzerland, perhaps with the potential for development into one of the world's largest sauropod tracksites. It will be protected in situ underneath an especially constructed highway-bridge, thus offering opportunities for future research and the development of an interpretative center for education and tourism.