Manus Prints Research Articles

Possible eucynodont (Synapsida: Cynodontia) tracks from a lacustrine facies in the Lower Jurassic Moenave Formation of southwestern Utah.

Eight fossil tetrapod footprints from lake-shore deposits in the Lower Jurassic Moenave Formation at the St. George Dinosaur Discovery Site (SGDS) in southwestern Utah cannot be assigned to the prevalent dinosaurian (Anomoepus, Eubrontes, Gigandipus, Grallator, Kayentapus) or crocodyliform (Batrachopus) ichnotaxa at the site. The tridactyl and tetradactyl footprints are incomplete, consisting of digit- and digit-tip-only imprints. Seven of the eight are likely pes prints; the remaining specimen is a possible manus print. The pes prints have digit imprint morphologies and similar anterior projections and divarication angles to those of Brasilichnium, an ichnotaxon found primarily in eolian paleoenvironments attributed to eucynodont synapsids. Although their incompleteness prevents clear referral to Brasilichnium, the SGDS tracks nevertheless suggest a eucynodont track maker and thus represent a rare, Early Mesozoic occurrence of such tracks outside of an eolian paleoenvironment.

Crocodile tail traces and dinosaur footprints. Bathonian?- Callovian. Imilchil. High Central Atlas. Morocco

Three types of ichnites from a new site discovered in Imilchil were studied and described. The structures of pes and manus prints and tail traces of tetrapods provide data to separate: real ichnites (theropod footprints and crocodile tail drag marks); and sauropod’ subtraces. Most of the theropod footprints are deformed by collapse of their walls, the sauropod subtraces show the strong deformation of about ten well-stratified sedimentary levels. The surface on which we can see theropod and crocodile ichnites is the tracking surface, i. e. the original surface on which they were printed.

The makers of Rhamphichnus ispp. reinterpreted as lepidosaurian and crocodilian, not pterosaurian

Three ichnospecies of the Late Jurassic trace fossil genus Rhamphichnus were first described and interpreted as the walking tracks of non-pterodactyloid pterosaurs like Rhamphorhynchus. This despite not resembling any previously identified pterosaur tracks and having a morphology unmatched by pterosaur skeletal elements. To fit the pterosaurian model, elongated imprints of R. pereiraensis and R. lafaurii, displaying four or five digit impressions were interpreted as manus prints, while shorter, five-digit prints were interpreted as imprints made by pedes with dislocated metatarsals and disarticulated phalanges. Comparison of published images and descriptions of Rhamphichnus ispp. to skeletal elements of six contemporaneous non-pterodactyloid taxa, skeletons and tracks from pterodactyloid pterosaurs, and modern and ancient lepidosaurs and crocodilians suggests an alternative interpretation. R. crayssacensis closely resembles crocodilian (Crocodylopodus (Sustenodactylus) isp.) and crocodylomorph (Batrachopus isp.) tracks; its holotype trackway was found 50 cm away from and parallel to a crocodilian swimming trackway with the same sized feet, possibly made by the same individual. R. pereiraensis and R. lafaurii strongly resemble lepidosaurian tracks and match the size and morphology of contemporary rhynchocephalians. Prints originally interpreted as manual and pedal in R. pereiraensis and R. lafaurii are reinterpreted and transposed in light of new data from pterosaurian, lepidosaurian, and crocodilian tracks and anatomy. Identification of fossil trackmakers depends on comparisons of a wide range of candidate taxa and elimination of those that cannot be considered further. With this reinterpretation of Rhamphichnus, there are no non-pterodactyloid pterosaurian tracks yet identified in the fossil record.

A new occurrence of archosaur footprints from the Löwenstein Formation (Late Triassic, Middle Norian) of southern Germany

Two sandstone slabs from a new Norian tetrapod tracksite in the Löwenstein Formation of southern Germany preserve a set of tracks including both tridactyl and pentadactyl ichnites, referred to theropod dinosaur and sphenosuchian crocodylomorph trackmakers, respectively. A very large manus print hints at the presence of a hitherto unknown large quadrupedal archosaur in the Norian fauna of southern Germany. The material includes one of the oldest records of crocodylomorph tracks presently known, in agreement with the skeletal record from the same formation.

A juvenile ornithopod tracksite from the Lower Cretaceous Haman Formation, South Korea

A new dinosaur tracksite with footprints of non-adult ornithopods was discovered from the Lower Cretaceous Haman Formation (Albian), Gunbuk District, Haman County, South Gyeongsang Province of South Korea in 2018. The tracksite consists of 58 ornithopod footprints (seven short trackways and 26 isolated footprints) within three track-bearing horizons partially exposed on the small creek bottom. Lithofacies and sedimentary structures of the track-bearing horizons and overlying strata suggest a marginal lacustrine environment. All tracks are sub-symmetrical tridactyl and small- to medium-sized pes prints. They have wide, blunt, short digital impressions with a large, rounded heel pad impression. No manus print is observable in the tracksite. Tracks are generally longer than their width with a distinctly developed digit III. Trackways show the inward (negative) rotation of footprints. The morphological characteristics of the footprints are most likely attributable to ichnogenus Caririchnium. A relatively small pes size (lengths range from 13 to 27 cm) indicates that the trackmakers were juvenile to subadult ornithopods when compared with the contemporary large ornithopods in South Korea. The majority of the trackways show preferred orientations with trends of parallel to subparallel groupings on each surface, suggesting gregarious behavior. Notably, the tracksite consists exclusively of juvenile ornithopod dinosaurs, which is an uncommon phenomenon when compared to other ornithopod tracksites with age-mixed or large ornithopod footprints reported from other localities around the world. The absence of the adult ornithopod tracks may be interpreted as the spatial segregation of an ornithopod population based on their ages and the formation of juvenile-only communities without parental care.

New ankylosaurian trackways (cf. Tetrapodosaurus) from an uppermost Cretaceous level of the El Molino Formation of Bolivia

Since the second half of the 20th Century, the study of fossil tracks in South America has steadily increased. A large number of tetrapod ichnogenera is currently known mainly from Argentina, Bolivia and Brazil. In this study, we present a new record consisting of several trackways that we refer to cf. Tetrapodosaurus, representing the first explicit mention of the ichnogenus in South America. These tracks come from the lacustrine to transitional El Molino Formation, deposited in Maastrichtian-Danian times, at the locality of Niñu-Mayu, near Sucre, Bolivia. These tracks preserve a quite similar manual morphology to that of Tetrapodosaurus borealis and minor differences in its pedal prints. Tetrapodosaurus is a typical ichnogenus of the northern hemisphere and commonly assigned to an ankylosaurian trackmaker. Tracks assigned to ankylosaurs were already reported from other sites of Bolivia, Brazil and tentatively Argentina; the new finding further improves our understanding of the ankylosaurian record from South America. A detailed morphological analysis allows us to make an accurate trackmaker identification and footprints are attributed to a member of the ankylosaurian family, the Nodosauridae. The trackways from Niñu-Mayu also have paleobiological implications. Manus prints are complete, pes prints generally lack the proximal region of the pes, the sole pad, expulsion rims are proximally placed in pes prints and the trackway parameters are highly variable, suggesting formation influenced by certain buoyancy of the trackmakers.

Turtle and pterosaur tracks from the Los Cayos Dinosaur Tracksite, Cameros Basin (Cornago, La Rioja, Spain): tracking the Lower Cretaceous bio-diversity

New fossil turtle and pterosaurian tracks have been found at the Los Cayos locality (Cornago township, La Rioja province, Spain). The Los Cayos tracksite is situated in the Cameros Basin, ant it is included in the Enciso Group, which is late Barremian-Early Aptian in age (Lower Cretaceous). The turtle tracks are formed by parallel isolated digit impressions. Digits show acuminate distal ends and relatively blunt proximal margins. Most of the tracks show three digits, and only two of them are pentadactyl. No trackways can be observed but only different track alignments suggesting some kind of direction of movement. Two track-bearing layers have yielded 5 pterosaur manus prints. No pes footprints or trackways have been discovered at these outcrops yet. These prints are tridactyl, with digit I, the shortest, and III, the longest. The angles between the digits are variable: angle I-II is significantly bigger than between II-III. These tracks from Los Cayos were the first discovery of pterosaur tracks in the Enciso Group.

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.

Footprints of Batrachopus isp. From the Imilchil megatracksite. Middle? - Upper Jurassic, central High Atlas (Morocco)

In this work we present the description and analysis of a palaeoichnological site (7.9TAG) that only contains crocodile tracks. The site contains well preserved and abundant crocodilian manus and pes prints; there are no belly and/or tail traces. The crocodyle tracks have been mapped and the biomorphic and morphometric characters of the tracks and trackways have been studied. Between the digit traces of the pes prints (not in manus prints) there is a graded depression that indicates the presence of a foot webbing. The number of crocodilian footprints (93) and trackways (8) of the site is sufficient to define, and to support with confidence the data shown in the article. As consequence a crocodiliform ichnogenus, Batrachopus has been defined, characterized by the presence of a trace of a probably interdigital membrane in the pes prints, the trace of a bulge on toe V, the lack of tail traces, and the very narrow gauge trackway. A comparative study is done with all the fossil crocodile footprints described so far. The 7.9TAG footprints printed on sediments of Middle?-Upper Jurassic age (Isli Formation) are the first Batrachopus ichnites described both from this age and in the African continent.

Polyonyx-like tracks from Middle-?Upper Jurassic red beds of Morocco: Implications for sauropod communities on southern margins of tethys

A new dinosaur tracksite is reported from continental red beds of the Jurassic (Late Bathonian-?Callovian) Isli Formation along the northern flank of the Aït Ali ou Ikkou Syncline of the Imilchil area, Central High Atlas, Morocco. The succession was deposited in a fluvio-lacustrine environment, and contains at least fourteen track-bearing levels. The diverse dinosaur-dominated ichnofauna includes the footprints of crocodylomorphs, pterosaurs, theropods, sauropods and ornithischians, together with numerous invertebrate traces. Here, we focus on a long sauropod trackway, which comprises nine consecutive manus-pes sets preserved as concave epireliefs. The low heteropody and asymmetry of manus prints with a large digit I (pollex) impression oriented medially, and a large triangular claw trace, which is posteriorly oriented, are characteristic of the ichnogenus Polyonyx. Different from typical Polyonyx is the narrow gauge pattern compared to the wide gauge observed in the type trackway from Portugal. Additional material from Morocco, similar to Polyonyx, comprises the trackway of a very small (?juvenile) individual found close to the main trackway, as well as a short trackway from a different locality in the Isli Formation. Our data from the Moroccan High Atlas indicates the presence of basal eusauropods in the Middle Jurassic-Early Cretaceous interval in the northwestern part of Gondwana for the first time, and suggests they inhabited a lacustrine paleoenvironment.

Large Carnivore Footprints from the Late Pleistocene of Argentina

ABSTRACTThe aim of the present contribution is to describe large felipedid footprints from a new ichnological site from the Late Pleistocene of Buenos Aires Province, Argentina. The prints are referred as the new ichnospecies Felipeda miramarensis nov. ichnosp. Based on size and morphology, this new ichnotaxon may have been produced by the large machairodontine felid Smilodon populator. Track analysis indicates that the producer of the tracks had fully retractile claws, a plantigrade feet, and lacked strong supination capabilities on pes and manus. The size and depth differences between manus and pes prints indicate that the producer had notably robust anterior limbs. If correctly assigned, the new ichnospecies reinforces the idea that Smilodon was an ambush predatory mammal.

Trackways of the American Crocodile (Crocodylus acutus) in Northwestern Costa Rica: Implications for Crocodylian Ichnology

ABSTRACTWe documented trackways of free-living Crocodylus acutus on beaches at the mouths of Tamarindo and Ventanas estuaries, Costa Rica. Our crocodiles had estimated total lengths of 1–3 meters or more. Manus prints have five digits, with digits I–III bearing claw marks. Pes prints have four digits, with claw marks on digits I–III. The pes is plantigrade. Claws generally dig into the substrate. Apart from claw marks, digit I and the heel of the pes are usually the most deeply impressed parts of footprints. Trackways are wide-gauge. Pes prints are usually positioned just behind ipsilateral manus prints of the same set and may overlap them. Manus and pes prints angle slightly outward with respect to the crocodile's direction of movement. Claw-bearing digits of both the manus and pes may create curved, concave-toward-the-midline drag marks as the autopodium is protracted. The tail mark varies in depth and clarity, and in shape from nearly linear to markedly sinuous. Sometimes the tail mark hugs the trackway midline, but sometimes it is closer to, or even cuts across, prints of one side. American crocodile footprints and trackways are similar to those observed in other extant crocodylian species, indicating substantial trackway conservatism across the group.

Anza palaeoichnological site. Late Cretaceous. Morocco. Part I. The first African pterosaur trackway (manus only)

Cretaceous pterosaurs tracksites are very rare worldwide. Until now,only one African Cretaceous site withtracks of (Agadirichnus elegans and Pteraichnus) was known. This makes the discovery of a new outcrop in the Upper Cretaceous of Anza (Morocco) the third manifestation of this type of footprint in Africa, extending the existence of such traces from the Coniacian-Santonian to the Maastrichtian. The site contains only manus tracks, which can be explained as a result of erosion of pes prints. The lack of pes prints and the morphometric characteristics of the manus prints only allow us to relate these prints to Agadirichnus, Pteraichnus or maybe to a new ichnogenus. It is possible that the trackmakers are related to Ornithocheiroidea or Azhdarchoidea superfamilies whose fossil bones have been found from the Late Cretaceous in Morocco.

Pentadactyl ankylosaurian manus tracks from the Lower Cretaceous of Galve (Teruel, Spain): first occurrence of Tetrapodosaurus in the Iberian Peninsula

This work is a detailed description of ankylosaurian natural casts found in Galve (Teruel, Spain), with the identification and classification of the major dynamic and static structures that depend on the phase of autopodial (hand) movement. Specimens come from the Lower Cretaceous (Barremian) of the eastern sector of the Iberian Range. The depositional environment is of continental coastal influence with both fluvial and tidal current structures. We studied the morphology and main features of approximately 50 manus casts of Tetrapodosaurus. The structures were correlated with the different stages of the movement during the formation of the print (footprint formation phases of Thulborn and Wade 1989). We describe the prints, lithological composition and the features observed at the top, the base and the walls of the casts (striae, lineations, grooves and polygonal scales) for understand the autopodial shape, the response of the pads and the hand movement. Manus prints of sauropods, stegosaurs and ankylosaurs may show a similar morphology. However, the presence of five perfectly-distinct, protruding and separate digits in the Galve specimens make these ichnites incompatible with those of stegosaurs or with those of sauropods. We examine the original definition and the diagnosis of Tetrapodosaurus, including other similar pentadactyl tracks; also the global distribution and palaeoenvironments of these ankylosaurian ichnites, and the possible affinities of the trackmaker. The first citation of Tetrapodosaurus in Galve (Spain) confirms the palaeontological importance of this area, due to the variety of sites and dinosaur fossil types found. Careful examination of the casts has allowed reconstruction of the kinds of joint and forelimb movements that are independent of, but consistent with, interpretations based on functional aspects of the forelimb skeleton. The structures observed in the walls and in the base of the casts indicate that the digital pads of the ankylosaur hands were flexible calluses.

NEW DINOSAUR TRACKSITE IN THE LATE JURASSIC OF KIRMENJAK QUARRY (ISTRIA)

A new dinosaur tracksite was found in the Kirmenjak quarry in Istria. It is located about one kilometre from an already existing tracksite. The footprints are placed on a slightly inclined bedding plane at the base of the succession represented by heavily stylolitised limestones of the Kirmenjak informal lithostratigraphic unit. The age of the limestones is late Tithonian. Fifteen footprints of circular shape with no clear digit or claw impressions were found at the site and are interpreted to have been formed on a tidal flat during a sea-level fall. All of the footprints belong to sauropod dinosaurs. Pes prints are circular to elliptical in shape, whereas manus prints are more elliptical and of smaller size. The average length of the pes prints is 55 cm, which would correspond to a sauropod of approximately 16 meters in length. The trackway is of narrow-gauge type, where the internal trackway width often has a negative value. The length of the strides indicates slow movement of the individual with a speed of less than 2 km/h. Based on stratigraphic position and footprint morphology, the new and the pre-existing tracksites represent the same trackbearing layer.

A New Look at Morphological Variation in the IchnogenusAnomoepus, with Special Reference to Material from the Lower Jurassic Newark Supergroup: Implications for Ichnotaxonomy and Ichnodiversity

Numerous new trackways of the small, ornithischian dinosaurs ichnogenus Anomoepus were discovered in the Lower Jurassic (Hettangian) East Berlin Formation in Holyoke, Massachusetts. This new material consists of 16 trackways, on two bedding surfaces 1.5 cm apart, all in close proximity to each other. The abundant pedal and manual impressions have well-preserved digital pad impressions, and claw marks are often discernible also. An Osteometric analysis allows reconstruction of the pedal digits and weight-bearing portions of the metatarsals. On the basis of their small size, as well as distinctive features and proportions of both the manus and pes impressions, these prints are assigned to the ichnospecies Anomoepus lacertoideus (comb. nov.). Three ichnospecies of Anomoepus can be recognized in the Lower Jurassic of the Newark Supergroup: A. lacertoideus, A. scambus and A. crassus. The A. lacertoideus footprints described herein provide evidence that this small, ornithischian track maker engaged in a variety of locomotion-related behaviors. Trackways mostly consist of digitigrade pes prints, reflecting bipedal locomotion, but intervals of quadrupedal progression also are documented by metatarsal and manus imprints in seven trackways. The longest trackways, each consisting of 10 to 15 pes impressions, vary in morphology as a result of the presence or absence of an impression of the distal parts of metatarsals II and IV. The manus prints show two distinct digital divarication angles, 120° and 180°, depending on whether the animal was walking normally or stopping. Variations in substrate consistency influenced locomotor behavior, as shown by the variable pattern of body weight distributions on the pedal digits. Such differences are especially apparent in the longest trackways, which vary in stride and pace lengths. The trends of the abundant trackways at this site also suggest group behavior in Anomoepus, something previously unrecorded for this ichnogenus in the Connecticut River Valley. Evidence from the East Berlin Formation suggests that ichnogenus Anomoepus is not monospecific as some authors have suggested.

A possible pterosaur manus track from the Late Cretaceous of Alberta

Bell, P.R., Fanti, F. & Sissons, R. 2012: A possible pterosaur manus track from the LateCretaceous of Alberta. Lethaia, DOI: 10.1111/let.12006.An isolated track from the latest Campanian–Maastrichtian Wapiti Formation (Alber-ta) is tentatively identified as a pterosaur manus print. The basic digital formula (digitI < digit II < digit III) is consistent with the plesiomorphic condition in pterosaurs.The track measures 25.5 cm in length, making it the largest putative pterosaur manusprint (estimated wingspan 7.7 m) from North America. Although precise chrono-stratigraphic data are lacking, sedimentary evidence indicates the track comes from amid- to late Campanian fluvial deposits that accumulated approximately 400 km fromthe closest shoreline within a high-latitude (65°N) setting.

Los Cayos S y D: dos afloramientos con icnitas de saurópodos, terópodos y ornitópodos en el Cretácico inferior del área de Los Cayos (Cornago, La Rioja, España)

Although most part of the Los Cayos area track-bearing layers have yielded almost non-avian theropod footprints, Los Cayos S and D have revealed the presence of fossil prints belonging to sauropods and ornithopods respectively. Los Cayos S contains ten track-bearing layers, but the most significant one shows a short sauropod trackway that, based on manus print morphology, it is identified with the ichnogenus Titanosaurimanus . This trackway was caused by a titanosaurid sauropod or at least by a titanosauriform. On the contrary, Los Cayos D has yielded abundant footprints —most of them isolated— that have been produced by relatively big ornithopod dinosaurs. We identify these tracks with the ichnogenus Iguanodontipus . The existence of both footprint morphotypes is very interesting for the Los Cayos area due to it represents the presence of large herbivorous dinosaurs in those Cretaceous ecosystems that produced the sediments of the Enciso Group.

FIRST RECORD OF DINOSAURS IN THE LATE JURASSIC OF THE ADRIATIC-DINARIDIC CARBONATE PLATFORM (CROATIA)

Abstract All previously known dinosaur remains on the Adriatic-Dinaridic carbonate platform (ADCP) were described from Cretaceous deposits. A new trackbearing locality is late Tithonian in age and represents the oldest evidence of dinosaurs on the ADCP. The site is in an active quarry near the village of Kirmenjak in western Istria. Almost a thousand sauropod footprints including 23 single trackways have been found on the outcrop. Oval impressions represent pes prints, and horseshoe-shaped impressions represent manus prints; pes prints are 23 to 52 cm long. Calculated heights at the hip range from 153 to 306 cm. The main direction of dinosaur movement was toward the northeast, and some of the individuals were moving together. The trackways show a characteristic narrow gauge, and pace and stride lengths indicate a slow walk. The footprints are similar to Parabrontopodus ichnogenus, and the ichnocoenosis could be assigned to the Brontopodus ichnofacies. The presence of the sauropods on the Adriatic-Dinaridi...

A NEW DINOSAUR TRACKSITE IN THE CENOMANIAN OF ISTRIA, CROATIA

The new locality with dinosaur footprints has been discovered in the port of Karigador village in Istria. The site is situated in peritidal limestones of late Cenomanian age. The track-bearing horizon is bioclastic wackestone-packstone deposited in a subtidal environment. A single trackway which consist of 28 pairs of footprints and a group of 4 track pairs was registered at the site. Trackways belong to quadrupedal dinosaurs and are assigned to sauropods. Oval-circular shaped footprints represent the pedal prints and horseshoe-semicircular shaped ones represent the manus prints. The trackway is of narrow-gauge type with outwardly rotated manus and pedal prints. The average length of the pedal prints is 33 cm what indicates the length of the individual of app. 10 m. The preferred gait of the individual was a normal walk, taking normal strides with a speed of around 3 km/h. The trackmaker was a non-titanosaurian sauropod. Together with the other late Cenomanian sauropod localities in Istria (Fenoliga and Ladin Gaj), the Karigador site represents an example of sauropod tracks in a carbonate platform environment which can be assigned to Brontopodus ichnofacies.