Pes Imprints Research Articles

Oligocene vertebrate footprints from the Lower Red Formation, Central Iran

The Lower Red Formation (LRF) in Central Iran consists of the alternation of red-brown terrigenous sediments, marls and evaporites with basalt intercalations, exposed under the Chattian-Burdigalian Qom Formation and deposited on Eocene volcaniclastic sediments. The LRF is considered Rupelian in age. In the Deh Nar area, between Qom and Kashan cities, the LRF includes a basal conglomerate, alternations of brown-red sandstone and shale, colored marls with evaporite diapirs and top eroded red sandstone, with dark gray and green basalt lava intercalations. These sedimentary rocks are deposited in fluvial and playa environments, influenced by volcanic activities. Lower sandstone layers of the LRF in Deh Nar contain numerous vertebrate footprints, mostly preserved as convex hyporeliefs. Bird footprints are identified as Ardeipeda egretta, Aviadactyla vialovi, Avipeda phoenix and Gruipeda dominguensis. Small bird footprints are attributed to small, incumbent anisodactyl shoreline birds, such as sandpipers, and the larger of them to Gruiformes and Ciconiiformes, such as Ardeidae and Ciconiidae. Mammal footprints include Dehnaripus incognitusign. nov. and isp. nov., Lophiopus isp., Moropopus elongatus, Moropopus kashanensisisp. nov., Platykopus stuartjohnstoni, and Zanclonychopus isp. Dehnaripus incognitus is large circular manus and pes imprints; usually, they show unorganized, large, radial surface wrinkles and their digital or metatarsal/ metacarpal imprints are ambiguous. Moropopus kashanensis is tridactyl mammal pes and manus imprints and is distinguished by sharp, claw-like imprints in lateral digits of the manus from Moropopus elongatus. Most probably, the mammal tridactyl footprints of Deh Nar made by three toed, medium- to large sized terrestrial herbivores perissodactyls such as Tapiroidea. Platykopus and Zanclonychopus, however, were remained by large carnivores such as Amphicyonidae or Ursidae. Trackmakers of footprints in the LRF of Deh Nar area lived under hot and dry conditions of terrestrial and evaporitic environments, after cool and dry conditions of the Early Oligocene.

A new pterosaur tracksite from the Lower Cretaceous of Wuerho, Junggar Basin, China: inferring the first putative pterosaur trackmaker.

We report the discovery of 114 small pterosaur footprints preserved in a greyish-green fine sandstone slab comprising 57 manus imprints and 57 pes imprints. Due to the chaotic distribution of footprints, the trackways are difficult to recognize. The pes imprints are sub-triangular and enlongate, the metatarsal part is roughly subequal to the digital part. The manus imprints are asymmetrical, longer than wide, and the lengths of digits I–III gradually increase. According to the diagnostic features of the Wuerho small pterosaur tracks, the present set was classified as Pteraichnus and is different from the nine reported valid ichnospecies of Pteraichnus. We therefore propose a new ichnospecies, Pteraichnus wuerhoensis isp. nov. The description is based on the anatomical characteristics (lengths of digits I–IV, length of digital part, length of metatarsal part) extracted from the pes imprints and comparisons with the pes bone fossils of Noripterus complicidens. We infer that the footprints were probably left by N. complicidens and the total width of the wings was presumably 2–2.3 m. In addition, the high density (365 per square meter) and varied sizes of the Wuerho small pterosaur tracks suggest that many pterosaurs of different ages lived in Huangyangquan Reservoir tracksite 1 area. Thus the trackmakers may have had gregarious behavior.

The first possible choristoderan trackway from the Lower Cretaceous Daegu Formation of South Korea and its implications on choristoderan locomotion

Here we report a new quadrupedal trackway found in the Lower Cretaceous Daegu Formation (Albian) in the vicinity of Ulsan Metropolitan City, South Korea, in 2018. A total of nine manus-pes imprints show a strong heteropodous quadrupedal trackway (length ratio is 1:3.36). Both manus and pes tracks are pentadactyl with claw marks. The manus prints rotate distinctly outward while the pes prints are nearly parallel to the direction of travel. The functional axis in manus and pes imprints suggests that the trackmaker moved along the medial side during the stroke progressions (entaxonic), indicating weight support on the inner side of the limbs. There is an indication of webbing between the pedal digits. These new tracks are assigned to Novapes ulsanensis, n. ichnogen., n. ichnosp., which are well-matched not only with foot skeletons and body size of Monjurosuchus but also the fossil record of choristoderes in East Asia, thereby N. ulsanensis could be made by a monjurosuchid-like choristoderan and represent the first possible choristoderan trackway from Asia. N. ulsanensis also suggests that semi-aquatic choristoderans were capable of walking semi-erect when moving on the ground with a similar locomotion pattern to that of crocodilians on land.

Unusual archosaur trackway and associated tetrapod ichnofauna from Irohalene member (Timezgadiouine formation, late Triassic, Carnian) of the Argana Basin, Western High Atlas, Morocco

ABSTRACT An archosaur trackway consisting of 10 successive pes imprints has been recovered from the Late Triassic Irohalene Member of the Timezgadiouine Formation (Argana Basin, Morocco). Footprints are tetradactyl-pentadactyl, and show an elongated ‘heel’, probably enclosing the trace of digit V. The trackway lacks a manus impression, which could be due to bipedal progression of the trackmaker or be a preservational phenomenon. It is assigned to cf. Parachirotherium isp. based on similarities with the ichnogenus that has been described from the same stratigraphic unit. Other footprints of this assemblage are assigned to the ichnotaxa Grallator-Eubrontes (dinosauromorphs/crocodilian-stem archosaurs), Brachychirotherium isp. (crocodilian-stem archosaurs), Rhynchosauroides isp. (lepidosauromorphs/archosauromorphs), and indeterminate ichnotaxa. Associated with the footprints are numerous invertebrate traces such as Scoyenia gracilis. The ichnofauna of the Irohalene Member supports a cosmopolitan distribution of pentadactyl but functionally tridactyl chirotheres (Parachirotherium) and grallatorids across the Ladinian-Carnian boundary. Similar assemblages are known from the Germanic Basin and from Eastern North America. Furthermore, it documents the occurrence of very large Eubrontes trackmakers in the early Carnian. The depositional environment of the lower part of the Irohalene Member is interpreted as wet red beds of a flood basin transitional to a distal braid plain.

Tracheria troyana (Krapovickas and Nasif, 2011): Redefinition, Environmental Distribution, and Heritage Conservation

ABSTRACTThe South American caviomorph ichnogenus Tracheria troyana is reevaluated here based on recently discovered specimens that allow a more thorough investigation of footprint taphonomy and ichnotaxonomy. The footprints include detailed autopodium morphology and more complete gait patterns than previously reported. The redefinition of T. troyana involves key aspects as digit impressions of the manus asymmetrically arranged and digit V being the shortest and at times do not print. It generally lacks metacarpal pads, resulting in almost digitigrade impressions and regularly preserved as tridactyl footprints. In the pes imprints, digits have a symmetrical arrangement. Phalangeal and metapodial pad impressions are preserved, occasionally showing the presence of two heel pads. Trackways denote a marked overstep in which the pes impressions are placed in front of the manus. New data about T. troyana environmental distribution shows that typically characterizes overbank facies of anastomosing and meandering fluvial systems, which may be reflecting a habitat preference the producer. Here, we also present new digitized 3D images of the original type material of T. troyana, in order to preserve these materials, which were previously only available for viewing in the field.

First Early Jurassic Ornithischian and theropod footprint assemblage and a new ichnotaxon Shenmuichnus wangi ichnosp. nov. from Yunnan Province, southwestern China

The new ichnospecies, Shenmuichnus wangi ichnosp. nov., is the first evidence for the presence of large ornithischians in the Early Jurassic of Yunnan Province, whereas the known skeletal record documents small species only. Until now Shenmuichnus was known from a single locality in Shaanxi Province by the ichnospecies Shenmuichnus youngteilhardorum. Compared with the latter, Shenmuichnus wangi is larger and shows a different trackway configuration, particularly in the relative position of manus and pes imprints. Palecologically, the occurrence of Shenmuichnus wangi in a red bed facies indicates the preference of distinctive environments of trackmakers of both ichnospecies, questioning former hypotheses of exclusivity of ornithischians in more humid climates. By abundance both skeletons and footprints of ornithischians suggest their role as a minor component in Early Jurassic saurischian dominated dinosaur faunas in this region.

Current situation of the ichnological locality of São Domingos from the Corda Formation (Lower Cretaceous), northern Tocantins state, Brazil

In the 80's, Leonardi treated the presence of a vertebrate ichnological locality from the Barremian Corda Formation, Parnaíba Basin, on the left bank of the Tocantins river, near of the São Domingos town, Itaguatins, State of Tocantins, Brazil. Originally, the record was composed of at least seven in situ trackways, accounting for fifty six tracks. Since 2011, the Hydroelectric Power Plant do Estreito has begun to work, causing the development of a water reservoir 160 km upstream to the ichnological site, causing periodic and highly energetic floods over the footprints-bearing level and altering it. The imprints are poorly to moderate preserved, but it is possible to distinguish the general morphology and the spatial arrangement of the footprints. The specimens are represented by pes imprints, mostly circular to subcircular, with no digital and claw impressions. No distinguishable manus imprints are present. The trackways are relative narrow with respect to the size of the tracks, so they are considered into the Parabrontopodus-like category. The São Domingos tracks have been originally assigned to iguanodontid dinosaurs, and posteriorly related to a sauropodian origin. This idea is herein accepted, particularly to a basal sauropod, basal macronarians, or diplodocoids. Up to date, the tracks from the São Domingos locality are the only vertebrate fossil record from the Corda Formation, meaning an important contribution to the Cretaceous ichnofauna from South America.

Carboniferous tetrapod footprints from the Lublin Basin, SE Poland

Evidence of tetrapod footprints is scarce in the Carboniferous rocks of Europe and only a dozen sites have been found. Here is presented the first description of the Carboniferous tetrapod traces collected from the Bogdanka Coal Mine, Lublin Basin, south-eastern Poland. The footprints occur in reddish, white-gray sandstone or black-brown siltstone-mudstone, fluvial and lacustrine in origin, of the Westphalian A and B (about 315 and 310 Ma, lower-middle Pennsylvanian) of the Lublin Formation. Based on the study of 19 specimens (isolated and usually poorly preserved manus or pes imprints), I discern two distinct types of tetrapod footprints and also problematic traces (or scratches) made by swimming tetrapods. Footprints are assigned to the two ichnotaxa: Batrachichnus–Limnopus plexus and aff. Pseudobradypus isp. Traces described as Tetrapoda indet. A–C represent poorly preserved footprints, which are similar to the ichnogenera Ichniotherium, Dimetropus and Attenosaurus. The described trace fossils were produced by small amphibians (temnospondyls) and medium-sized amniotes (reptiliomorphs and reptiles). The tetrapod ichnofauna from the Bogdanka Coal Mine is similar in composition to Pennsylvanian ichnofaunas from Europe and North America.

First chirothere and possible grallatorid footprint assemblage from the Upper Triassic Baoding Formation of Sichuan Province, southwestern China

Trackways of archosaurs have recently been discovered in sandstones of the Upper Triassic (Norian–Rhaetian) Baoding Formation of Panzhihua City in southern Sichuan Province, China. Based on their overall-morphology, pes imprints are of characteristic chirotheriid shape showing a compact and symmetrical anterior group of digit traces II–IV with the trace of digit III being the longest, and a posterolaterally positioned, long and slender trace of digit V. Imprints of digit I and the manus are not preserved. This could be related to substrate conditions and the relatively shallow impressions, even if peculiarities in the gait such as overstep of the manus by the pes or bipedal movement cannot completely be excluded. Ichnotaxonomically, the imprints are assigned tentatively to cf. Chirotherium. There are some similarities with the type ichnospecies C. barthii from the Middle Triassic that has a global distribution and that was described also from the Guanling Formation (Middle Triassic) of adjacent Guizhou Province. However, the long and slender digit V that lacks a distinct large oval basal pad, the relatively short stride/step length, the low pace angulation, and the slight inward rotation of the imprints toward the midline are different. The peculiar shape of digit V and the lack of digit I in all imprints also preclude an assignment to the common Late Triassic ichnogenus Brachychirotherium or similar ichnotaxa such as Pseudotetrasauropus. An isolated tridactyl footprint on the same surface is different in shape from the chirotheriid ones by the stronger mesaxony and narrower digit divarication. It is considered here as a possible large grallatorid. This is the first occurrence of tetrapod footprints in the Baoding Formation of Sichuan Province and the second record of chirotheriids in the Triassic of China. The Baoding Formation has also yielded a characteristic Upper Triassic flora with cycads, filicopsids, gingkos, and conifers as well as bivalve fossils. The depositional environment can be designated as fluvial-lacustrine with occasional opening to marine areas. Considering biostratigraphic and palaeobiogeographic aspects, the late occurrence of chirotheriids cf. Chirotherium in China supports the view that basal crown-group archosaurs with a distinct tendency toward a functionally tridactyl pes developed and dispersed in parallel to typical tridactyl dinosaurs.

First perissodactyl footprints from Flysch deposits of the Barail Group (Lower Oligocene) of Manipur, India

Two pes imprints of a perissodactyl mammal constituting a single step of a trackway have recently been discovered in Oligocene Flysch deposits of the Barail Group in Manipur, India. The tridactyl, mesaxonic imprints (~7 cm in length) show strong similarities to footprints known from the Paleogene of China and can be attributed to a tapiroid, rhinocerotoid or equoid trackmaker. This is the first record of perissodactyl footprints from the Lower Oligocene of India and the first evidence of mammals in the Barail Group of the age. Remarkable is the occurrence in a marginal marine setting, whereas other known perissodactyl footprints from the Eocene–Oligocene in particular from North America, Europe and China come from fluvio-lacustrine strata.

Metatetrapous valdensis Nopcsa, 1923 and the Presence of Ankylosaur Tracks (Dinosauria: Thyreophora) in the Berriasian (Early Cretaceous) of Northwestern Germany

Metatetrapous valdensis Nopcsa, 1923 from the late Berriasian of northwestern Germany was the first dinosaur ichnotaxon ever attributed to a thyreophoran trackmaker. However, the subsequent lost of the original material made this identification and the status of the ichnotaxon questionable for many subsequent authors. This situation was aggravated by the fact that there are only very brief original descriptions accompanied by a single drawing. A reconsideration of the original description recognizes M. valdensis as a valid ichnotaxon, which, albeit showing great resemblance in pes morphology to similar ichnotaxa, stands out from them by a tetradactyl manus. It not only holds its original systematic attribution, but also has sparked early hypotheses on the phylogeny of dinosaurs already in 1922, possibly for the first time based upon tracks. Two surviving natural hypichnial casts of ankylosaurian pes imprints from the same stratum cannot be straightforwardly identified with the type material due to a lack of documentation. However, comprehensive circumstantial evidence, including complete accordance in size and morphology among others, strongly supports such an association. The tracks confirm the presence of ankylosaurs in this lacustrine-deltaic setting as a very rare element of the local dinosaur fauna.

An unusual trackway of a possibly bipedal archosaur from the Late Triassic of the Sichuan Basin, China

The Longguan dinosaur tracksite in the Sichuan Basin (China) is described. It is located in the uppermost part of the Upper Triassic Xujiahe Formation and displays a single, unusual trackway consisting of 19 deeply impressed pes imprints. All tracks have suffered from erosion over many years of exposure, but they still reveal interesting details such as conspicuous elongated grooves, interpreted here as toe and claw drag marks. The trackmaker, a medium-sized archosaur, was walking in a thick and relatively soft layer of sand. The elongated, oval shape of the footprints resembles the ichnogenus Eosauropus from North America and Europe, assigned to facultative bipedal sauropodomorphs. The Chinese track differs by inward rotation of the footprints toward the midline, whereas in Eosauropus, these are turned strictly outward. Other ichnotaxa and possible trackmakers are discussed, but presently, a distinct assignment cannot be given. The Longguan trackway enlarges the scarce footprint record from the Triassic ...

Historical and Comparative Study of the First Spanish Vertebrate Paleoichnological Record and Bibliographic Review of the Spanish Chirotheriid Footprints

In 1897, Salvador Calderón y Arana published a study of the first vertebrate footprint from Spain. It was found in the Buntsandstein of Rillo de Gallo (Guadalajara), probably in the Rillo Mudstone and Sandstone Formation (middle Anisian-Landian). This isolated left pes imprint was classified as “Cheirotherium” sp. We conducted a historical study of this specimen, mentioned by several authors for more than a century, but never analyzed in detail. This well-preserved footprint, in which skin marks are present, is described here. Its characters are compared with those of valid chirotheriid ichnogenera. This work is complemented with a bibliographic analysis of the chirotheriid footprints recorded in Spain. This record is remarkable for its abundance and ichnodiversity.

Vertebrate Footprints from the Miocene Upper Red Formation, Shokorchi Area, Zanjan Province, NW Iran

Bird, carnivore, and artiodactyl mammal footprints were found in the Miocene Upper Red Formation in the Shokorchi area, west Zanjan, NW Iran. The Upper Red Formation section (about 50 m thick) to the east of Shokorchi village is mainly composed of marls and hard, thin- to thick-bedded sandstone layers. Sinuous ripple marks, mud cracks, and raindrop prints are common on the bedding planes, and flute casts and ripple marks show north-northwest to south-southeast paleocurrent directions. The bird tracks include digitigrade tridactyl footprints without hallux or metatarsus imprints and are assigned to Iranipeda, Antarctichnus and Avipeda isp. These bird tracks were made mainly by charadriiform birds such as sandpipers or snipes and large birds such as cranes. Mammal tracks include carnivore footprints with manus and pes imprints. The manus imprints are better preserved than the pes imprints and are semiplantigrade with five short digits. Digit V is clearly distinct from digits I-IV. The tips of manus digit traces are rounded without claw marks. The pes imprints are poorly preserved as a rounded or oval shape with no digit imprints and only one or two depressions in the mid to front parts of pes imprints. It seems that these footprints belonged to a carnivore in which the forefeet supported most of the animal's weight. These imprints determined as Platykopus ilycalcator and were made by large ursid. Artiodactyl footprints vary from wedge to rounded rectangular or heart shaped. Digits III and IV imprints are distinct with interungual ridges in the median or posterior region. The artiodactyl footprints are Pecoripeda (Gazellipeda) gazella, and because of the high density of tracks, distinguishing pes and manus imprints are impossible. These may have been made by a herd of artiodactyls that traversed a broad area.

The first pterosaur trackways from Japan

In 1990, five well-preserved pterosaur trackways were discovered in the Kitadani Formation (Lower Cretaceous) of the Kitadani Dinosaur Quarry, Fukui Prefecture, Japan. They occur on the surface of an isolated dark grey siltstone slab (70 × 50 cm) along with amphibian and bird tracks as well as feeding marks. All pterosaur trackways (a total of 64 imprints) show a clear quadrupedal gait pattern comprising manus and pes prints which reflect their detailed anatomy of the feet. Manus and pes imprint is very small, average 22.6 mm and 21.9 mm long, respectively. The manus has an anteriorly oriented digit I imprint with a medially oriented hook-like sharp claw mark, which makes a high divarication (average 155.4°) between the posteriorly oriented digit III imprint. The high digital abduction clearly shows that digit I of the manus could be more hyper-extended anteriorly than previously thought: spreading the digits as much as possible would provide a more stable contact with substrate as well as better support the center of pterosaur body mass displaced anteriorly. The interdigital webbing of the pes imprint extends from the metatarso-phalangeal joint near to the bases of four claws. As these features clearly distinguish the Kitadani pterosaur trackways from five known ichnospecies of Pteraichnus, we assign them to a new ichnospecies, Pteraichnus nipponensis. Abundant small pterosaur ichnotaxa from Spain, Korea, and Japan indicate that many small pterodactyloid pterosaur species existed in the Early Cretaceous although there is no single skeletal datum yet.

New pterosaur tracks from the Hasandong Formation (Lower Cretaceous) of Hadong County, South Korea

In 2004, fifty new pterosaur tracks were discovered in the Hasandong Formation (Lower Cretaceous), South Korea. They are preserved as natural casts on the surface of an isolated dark grey mudstone block (70 × 50 cm). Manus and pes imprints are very small, averaging 25.6 mm and 25.7 mm long, respectively. The manus imprints (N = 25) are tridactyl and digit I, II, III are strongly asymmetric. Fully plantigrade pes imprints (N = 25) were left by elongate metatarsals with short four digits (the ratio of digit to whole pes length is 2.6). There is no trace of the 5th phalanx of the pes. As these features clearly distinguish the Hadong tracks from the type species of the ichnogenus Pteraichnus, we assign them to a new species, Pteraichnus koreanensis. They are stratigraphically the oldest pterosaur tracks in Korea and are distinguished by size and morphology from the two pterosaur ichnotaxa, Haenamichnus uhangriensis and Pteraichnus isp., previously reported from the Uhangri and Haman formations. Pteraichnus koreanensis is the smallest pterosaur track currently reported from Asia.

China: Panzhihua/Pangang — nanoparticulate TiO 2

Trackways of archosaurs have recently been discovered in sandstones of the Upper Triassic (Norian–Rhaetian) Baoding Formation of Panzhihua City in southern Sichuan Province, China. Based on their overall-morphology, pes imprints are of characteristic chirotheriid shape showing a compact and symmetrical anterior group of digit traces II–IV with the trace of digit III being the longest, and a posterolaterally positioned, long and slender trace of digit V. Imprints of digit I and the manus are not preserved. This could be related to substrate conditions and the relatively shallow impressions, even if peculiarities in the gait such as overstep of the manus by the pes or bipedal movement cannot completely be excluded. Ichnotaxonomically, the imprints are assigned tentatively to cf. Chirotherium. There are some similarities with the type ichnospecies C. barthii from the Middle Triassic that has a global distribution and that was described also from the Guanling Formation (Middle Triassic) of adjacent Guizhou Province. However, the long and slender digit V that lacks a distinct large oval basal pad, the relatively short stride/step length, the low pace angulation, and the slight inward rotation of the imprints toward the midline are different. The peculiar shape of digit V and the lack of digit I in all imprints also preclude an assignment to the common Late Triassic ichnogenus Brachychirotherium or similar ichnotaxa such as Pseudotetrasauropus. An isolated tridactyl footprint on the same surface is different in shape from the chirotheriid ones by the stronger mesaxony and narrower digit divarication. It is considered here as a possible large grallatorid. This is the first occurrence of tetrapod footprints in the Baoding Formation of Sichuan Province and the second record of chirotheriids in the Triassic of China. The Baoding Formation has also yielded a characteristic Upper Triassic flora with cycads, filicopsids, gingkos, and conifers as well as bivalve fossils. The depositional environment can be designated as fluvial-lacustrine with occasional opening to marine areas. Considering biostratigraphic and palaeobiogeographic aspects, the late occurrence of chirotheriids cf. Chirotherium in China supports the view that basal crown-group archosaurs with a distinct tendency toward a functionally tridactyl pes developed and dispersed in parallel to typical tridactyl dinosaurs.