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First Upper Cretaceous dinosaur track assemblage from Jordan (Middle East) : preliminary results

Klein Hendrik, Gierliński Gerard, Lallensack Jerns N., Abu Hamad Abdalla, Al-Mashakbeh Habes, Alhejoj Ikhlas, Konopka Marcin, Błoński Marcin

Annales Societatis Geologorum Poloniae

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2020

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Vol. 90, No. 3

331--342

EN

Dinosaur tracks from Jordan (Middle East) have only been briefly reported in geological overview papers and books. We present here the first description and documentation of Jordanian dinosaur tracks based on a new tracksite from the south-central part of the country. The track-bearing strata belong to marginal marine (tidal flat) deposits of the Na’ur Formation (Upper Cretaceous, Cenomanian). This unit largely consists of well-bedded limestones, dolomites and marls that contain abundant marine invertebrate fossils such as bivalves, ammonites and foraminifers. The dinosaur ichnofauna occurs on four different levels and comprises abundant theropod tracks and trackways as well as isolated sauropod and ornithopod tracks. Theropod trackways consist of two different morphotypes. Morphotype 1 is tridactyl (26 cm pes length) and with a broad, but short metatarsal area and resembles the ichnogenus Picunichnus from the Lower Cretaceous (Albian) of Argentina. Morphotype 2 (36 cm pes length) has extensive and narrow metatarsal impressions continuously occurring along regularly-spaced trackways. This suggests either a plantigrade movement of the trackmaker or reflects preservational factors. By their over-all-shape with thin digits, Morphotype 2 resembles described penetrative tracks suggesting a strong influence of the substrate. Sauropod tracks are relatively small (40 cm pes length) and show low heteropody with a kid-ney-shaped manus imprint, pointing to a Sauropodichnus-like form. The single ornithopod pes track (18 cm in length) is similar to material described as Ornithopodichnus from the Lower Cretaceous of Korea. Due to the incomplete material of sauropod and ornithopod prints, no concrete assignment is given to this material and further study is needed. The presence of dinosaur tracks proves a temporary subaerial exposure of the surface whereas the main part of the Na’ur Formation is dominated by subaqueous activity of marine faunas.

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Jurassic tetrapod footprint ichnofaunas and ichnofacies of the Western Interior, USA

Lockley M., Gierlinski G.

Volumina Jurassica

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2014

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Vol. 12, no. 2

133-150

EN

The Jurassic tetrapod track record of the Western Interior, USA, is one of the most diverse, complete and well-studied in the world, spanning a relatively continuous representation of Lower, Middle and Upper Jurassic formations. Although a few of these formations, notably the Morrison Formation, have yielded abundant body fossils, the majority lack abundant skeletal remains and, while trackrich, are in some cases completely barren of body fossils. Thus, the track record assumes great importance as the most complete and representative record of changing tetrapod faunas through time in a region where the body fossil record is often sparse or absent. In the Lower and Middle Jurassic, many distinctive assemblages are associated with eolian units (Wingate, Navajo and Entrada) that are almost devoid of body fossils. However, the former two units are rich in synapsid tracks characterized as the Brasilichnium ichnofacies. In the Middle Jurassic, fluctuating sea-levels exerted important controls on the distribution of theropod and pterosaur-dominated ichnofaunas associated with coastal plain and marginal marine settings. The Morrison ichnofauna is a reliable reflection of the body fossil record of that formation. Ongoing efforts to group and classify the various tetrapod ichnofaunas into tetrapod ichnofacies and tetrapod biochron categories have, in some cases, provoked stimulating, if sometimes inconclusive, debate.

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Candidate sections for the GSSP of the base of the Bathonian Stage (Middle Jurassic)

Fernandez-Lopez S.

Volumina Jurassica

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2009

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Vol. 7, no. 1

77-88

EN

In accordance with the recommendations of the International Commission on Stratigraphy (ICS), the leading candidate for the Global Boundary Stratotype Section and Point (GSSP) of the base of the Bathonian Stage is located in the Ravin du B?s (Bas Auran area, SE France). This section was formally proposed as candidate nineteen years ago. A second potential candidate section is located in the Cabo Mondego area (Portugal). This Portuguese section, however, has not been formally proposed as a candidate for the Bathonian basal boundary stratotype. The formal selection and proposal of a GSSP for the Bathonian Stage is the responsibility of the Bathonian Working Group (BtWG) and is expected by September 2007. In accordance with the procedures to ratify GSSPs, a formal ballot on the selection and proposal of a GSSP for the Bathonian Stage, by post or email, by all members of the BtWG is the responsibility of the convenor and the International Subcommission on Jurassic Stratigraphy Executive, and will be carried out within this time scale.

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A Grallator-dominated tracksite from the Chinle Group (Late Triassic), Moab, Utah

Lockley M. G., Gierlinski G. D.

Geological Quarterly

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2009

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Vol. 53, No 4

433-440

EN

Two roadside localities on the northern fringes of Moab, Grand County, Utah yield previously un-described Upper Triassic vertebrate tracks from the Chinle Group (Rock Point Formation). The first locality, designated the high way 191 site, yields dozens of small theropod dinosaur tracks (Grallator) preserved on a single, fallen slab. The tracks form a monospecific assemblage preserved as natural casts. The assemblage is representative of what has been referred to as Rhaetic assemblage II which is dominated by small Grallator tracks. In situ Grallator tracks are also described from a nearby locality, referred to as the Matrimony Spring site, where they are found in association with the ichnogenus Brachychirotherium. Many other sites with similar, often more-diverse, Late Triassic ichnofaunas are known from the region.

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Global Jurassic tetrapod biochronology

Lucas S.

Volumina Jurassica

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2008

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Vol. 6, no. 1

99-108

EN

Jurassic tetrapod fossils are known from all of the continents, and their distribution documents a critical paleobiogeographic juncture in tetrapod evolution – the change from cosmopolitan Pangean tetrapod faunas to the provincialized faunas that characterize the late Mesozoic and Cenozoic. Two global tetrapod biochronological units (faunachrons) have been named for the Early Jurassic – Wassonian and Dawan – and reflect some Early Jurassic tetrapod cosmopolitanism. However, after the Dawan, a scattered and poorly-dated Middle Jurassic tetrapod record and a much better understood Upper Jurassic tetrapod record indicate that significant provincialization of the global tetrapod fauna had begun. Middle Jurassic tetrapod assemblages include distinct local genera of sauropod dinosaurs, which are large, mobile terrestrial tetrapods, and this suggests marked provinciality by Bajocian time. The obvious provincialism of well known Chinese Middle-Upper Jurassic dinosaur faunas also documents the end of tetrapod cosmopolitanism. The distribution of some Late Jurassic dinosaur taxa defines a province that extended from the western USA through Europe into eastern Africa. Provincial tetrapod biochronologies have already been proposed for this province and for the separate eastern Asian Late Jurassic province. Tetrapod footprints only identify two global assemblage zones, one of Early Jurassic and the other of Middle-Late Jurassic age. The incomplete state of Jurassic tetrapod biochronology reflects both an inadequate record with poor temporal constraints and a relative lack of study of the biostratigraphy of Jurassic fossil vertebrates.

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Reptile tracks (Rotodactylus) from the Middle Triassic of the Djurdjura Mountains in Algeria

Kotański Z., Gierliński G., Ptaszyński T.

Geological Quarterly

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2004

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Vol. 48, No 1

89--96

EN

In 1983, during stratigraphic investigations in the Djurdjura Mountains, vertebrate tracks were discovered in the Middle Triassic Haizer–Akouker Unit at the Belvédčre (Bkherdous) locality in Algeria. The footprints are about 2 cm long and consist of impressions of four clawed digits (I–IV), plus a reverted digit V. Manus imprints were overstepped by those of the pes. Originally interpreted as lizard footprints, they have been recently diagnosed as Rotodactylus cf. bessieri Demathieu 1984. In the current literature, Rotodactylus trackmakers are regarded as a group closest to dinosaurs among stem archosaurs. The footprints demonstrate a terrestrial sedimentary regime in the Maghrebids area during the ?late Anisian.

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New ornithischian dinosaur footprints in the Jurassic of Poland

Gierliński G., Gaździcka E., Niedźwiedzki G., Pieńkowski G.

Geological Quarterly

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2001

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Vol. 45, No 2

205-210

EN

New stratigraphic horizons with the ornithischian footprints have been found in central Poland. Basal thyreophoran ichnites are reported from the middle Hettangian Skloby Formation of Gromadzice. They support the previous conclusion that small and medium-sized Early Jurassic ornithischians preferred a coastal habitat with low-rise vegetation. Another find, an ornithopod footprint, came from the early Kimmeridgian Glowaczow Formation of Ożarow quarry. The track was discovered within the shallow-marine succession of calcareous deposits, which contributes to the interpretation of synsedimentary emersion of that area during the early Kimmeridgian.