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

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Annales Societatis Geologorum Poloniae (2020), vol. 90: 331 – 342 doi: https://doi.org/10.14241/asgp.2020.10
FIRST UPPER CRETACEOUS DINOSAUR TRACK ASSEMBLAGE
FROM JORDAN (MIDDLE EAST) – PRELIMINARY RESULTS
Hendrik Klein 1 *, Gerard GierlińsKi 2, Jens N. lallensacK 3, Abdalla abu Hamad 4,
Habes al-masHaKbeH 5, Ikhlas alHejoj 4, Marcin KonopKa 6 & Marcin błońsKi 7
1 Saurierwelt Paläontologisches Museum, Alte Richt 7, D-92318 Neumarkt, Germany;
e-mail: hendrik.klein@saurierwelt.de
2 Polish Geological Institute, Rakowiecka 4, 00-975, Warszawa, Poland;
e-mail: gierlinski@yahoo.com
3 School of Natural Sciences and Psychology, Liverpool John Moores University,
James Parsons Building, Bryon Street, Liverpool L3 3AF, UK;
e-mail: jens.lallensack@gmail.com
4 Environmental and Applied Geology Department, The University of Jordan, 11942 Amman, Jordan;
e-mail: a.abuhamad@ju.edu.jo; i.alhejoj@ju.edu.jo
5 Department of Applied Earth and Environmental Sciences, Al al-BaytUniversity, Mafraq, Jordan;
e-mail: Habes2819@aabu.edu.jo
6 Department of Sports Cardiology and Noninvasive Cardiovascular Imaging,
Medical University of Warsaw, Kondratowicza 8, 03-242 Warsaw, Poland;
e-mail: marcin.konopka@op.pl
7 Department of Musculoskeletal Trauma Surgery and Orthopaedics,
Centre of Postgraduate Medical Education, Konarskiego 13, 05-400 Otwock, Poland;
e-mail: mblo@wp.pl
*Corresponding author
Klein, H., Gierliński, G., Lallensack, J. N., Abu Hamad, A., Al-Mashakbeh, H., Alhejoj, I., Konopka, M.
& Błoński, M., 2020. First Upper Cretaceous dinosaur track assemblage from Jordan (Middle East) – preliminary
results. Annales Societatis Geologorum Poloniae, 90: 331 – 342.
Abstract: Dinosaur tracks from Jordan (Middle East) have only been briey reported in geological overview
papers and books. We present here the rst 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
at) 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 mor-
photypes. 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 reects preservational factors. By their over-
all-shape with thin digits, Morphotype 2 resembles described penetrative tracks suggesting a strong inuence
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.
Key words: Ajlun Group, Na’ur Formation, Cenomanian, footprints, theropod, sauropod, ornithopod.
Manuscript received 17 June 2020, accepted 9 September 2020

332 H. Klein et al.
Cretaceous dinosaur tracksites have been described in
numerous articles, documenting extensive material from
all continents, and mentioning only the most important
here would go beyond the scope of this paper. More recent
studies have been provided, for example, by Romilio et al.
(2013), Xing et al. (2015a, b), Segura et al. (2016), Lockley
et al. (2018), and Heredia et al. (2020). For an overview see
references therein.
Dinosaur tracks from the Middle East are scarcely known.
Thus far, reports concern theropod, sauropod and orni-
thopod tracks from the Upper Jurassic of Yemen (Schulp
et al., 2008a; Schulp and Wosabi, 2012; Al-Wosabi and Al-
Aydrus, 2015), theropod tracks from the Upper Cretaceous
(Cenomanian) of Jerusalem (Avnimelech, 1962a, b), or-
nithopod tracks from the Lower Cretaceous of Palestine
(Owais, 2020) and possible sauropod and other tracks from
the Lower Cretaceous of Lebanon (Gèze et al., 2016). From
Jordan, dinosaur tracks were briey mentioned by Bandel
and Salameh (2013, pp. 125, 133). According to these au-
thors, they occur in the uppermost Kurnub Group (Lower
Cretaceous, Albian) in interdunal sediments of Wadi Salihi
north of Amman. Here we present the rst documentation
of dinosaur tracks from Jordan that have recently been
found in the overlying Na’ur Formation (Ajlun Group).
The locality has the local name Jabal Safaha and is locat-
ed in the south-central part of the country, southwest of the
city of Shobak (30°29′48.77″N; 35°28′31.80″E; Fig. 1A).
It was discovered in 2019 by two of us, Marcin Konopka
and Marcin Błoński, while tracking the wadis between
Shobak and the historical Petra site. In the fall of the same
year, the authors started an expedition to the tracksite to re-
locate and document the surfaces. In the following, we
present preliminary results that will be elaborated on by
future, more detailed eldwork in the area
GEOLOGICAL SETTING
The footprints described here come from four different
levels in the Na’ur Formation of the Ajlun Group (Upper
Cretaceous, Cenomanian; Fig. 1B, C) that was rst intro-
duced by Quenell (1951). The Ajlun Group crops out in
northern, central and southern Jordan, and can be traced
from Ajlun in the North to Ras an Naqab in the South.
The lower boundary of the Ajlun Group is marked by the
rst appearance of the Wadi Juheira Member of the Na’ur
Formation, representing the rst marine transitional zone
above the Kurnub Group (Fig. 1B). In northern and cen-
tral Jordan the upper boundary is marked by the presence
of pelagic chalk deposits of the Belqa Group (Wadi Umm
Ghudran Formation), while to the south this facies is gradu-
ally replaced by chert, phosphatic, quartz-arenitic and dolo-
mitic rocks. The Ajlun Group has been variously considered
Albian-Early Cenomanian in age (Wetzel and Morton 1959;
Bender 1974), or the top being late Turonian in age (Wetzel
and Morton, 1959; Basha 1978). Six formations are recog-
nized in this group (Fig. 1B). The thickness is variable from
166 m in Ras an Naqab, southern Jordan, 515 m in Mujib,
central Jordan, to 253 m in Burma, northern Jordan.
The Na’ur Formation in the study area is ~80 m thick sec-
tion which begins with ~20 m of ne- to medium-grained
sandstone and glauconitic sandstone-siltstone, followed by
the carbonate unit.
The footprints occur on upper bedding planes of hard
limestone and dolomitic limestone beds that are about
INTRODUCTION
Fig. 1. Location and stratigraphy. A. Map of Jordan with the position of the study area and the tracksite (star icon). B. Stratigraphy
of the Early–Late Cretaceous units in Jordan and position of the described dinosaur tracksite in the Na’ur Formation (footprint icon).
Modied after Powell and Moh’d (2011). C. Lithostratigraphic section showing the succession of Ajlun Group deposits in Wadi Mujib,
central Jordan. Modied after Abed (2017).

333First Upper CretaCeoUs dinosaUr traCk
0.5–1.5 m thick. These were exposed by erosion of the in-
terbedded marls.
In the north of Jordan four members have been recognized
in the Na’ur Formation, whereas in the south these are un-
identiable. The Na’ur Formation rests unconformably on
the uvial Lower Cretaceous Kurnub Group that locally has
yielded dinosaur footprints (see above; Powel and Moh’d,
2010; Bandel and Salameh, 2013), while the former is rich
in marine body fossils such as foraminifers, bivalves, gas-
tropods, ammonites, ostracods, echinoids, sponges, corals,
stromatolites and sh teeth (Bandel and Salameh, 2013).
Burrows and more intensive bioturbation, by different in-
vertebrates, are common, and Bandel and Salameh (2013)
mention Ophiomorpha, Planolites and Thalassinoides. The
age of the strata is well-dened based on ammonites and
foraminifera (Schulze et al., 2005; Khalifa and Abed, 2010).
The track-bearing unit was deposited in a shallow marine
and tidal at environment with uctuating water levels.
Surfaces with ripple marks are common. In the Cenomanian,
Jordan was positioned at the northwestern border of the
Arabo-Nubian shield. It was largely ooded by transgres-
sions from the southern Tethys ocean and controlled by the
shelf sea during the whole of the Late Cretaceous (Bandel
and Salameh, 2013). The warm Cretaceous climate and
high water temperatures favoured deposition of carbonate
sediments, partly from algae and cyanobacterial produc-
tion, while uvial and deltaic siliciclastic input came from
rivers originating from the African continent (Bandel and
Salameh, 2013).
MATERIAL AND METHODS
The studied material consists of ve trackways and nu-
merous isolated specimens preserved as concave epireliefs.
All were examined directly in the eld and in situ under
natural light conditions. They were catalogued and consec-
utively numbered with the prex SPMN-JTP = Saurierwelt
Paläontologisches Museum Neumarkt, Jordan Track Project.
All specimens were left in the eld. Photogrammetric doc-
umentation was performed using a Nikon D5200 with an
18–70 mm Nikkor lens and photos processed in Agisoft
Metashape 1.6.3 Standard Edition (agisoft.com). The re-
sulting 3D models were tted to the horizontal plane us-
ing MeshLab v2020.6 (meshlab.net), and 2D visualizations
including orthophotographs, height maps, ambient occlu-
sions and inclination plots produced with ParaView 5.8
(paraview.org; for further details see Lallensack et al., in
press). Interpretive outline drawings were made on transpar-
ency lm and digitalized in Adobe Illustrator CS5 software.
Measurements were taken based on standard procedures
recommended by Leonardi (1987; Table 1).
The quality of track preservation is determined using
the scale of Marchetti et al. (2019).
DINOSAUR TRACKS
Theropod tracks cf. Picunichnus
Material. Trackway SPMN-JTP 1 consisting of 7 successive
pes imprints; trackway SPMN-JTP 2 with 6 successive pes
imprints; several indistinct trackways and isolated imprints,
uncatalogued; all on the lowermost (main) track surface
(Figs 2, 3A–D, 4; Table 1).
Description. Mesaxonic tridactyl imprints, longer than wide
but relatively broad, 21–26 cm in length and up to 18 cm
in width, some deeply impressed (up to 5 cm), with robust
broad and relatively short digits terminating in elongated
sharp claw traces. Digit proportions with digit III long-
est, II and IV shorter, with digit IV being longer than dig-
it II. No hallux impression can be observed. Divarication
Tracktype cf. Picunichnus Elongate theropod tracks Sauro-
pod
Ornitho-
pod
Specimen SPMN-JTP 1 SPMN-JTP 3 SPMN
-JPT 5
SPMN
-JTP 6
SPMN-
JTP 7
pl 26* 36* 24* 40 18
pw 18* 11* 10* 37 20
pl/pw 1.4* 3.3* 2.4* 1.1 0.9
ml – – – – – – – – – – – – – 20 –
mw – – – – – – – – – – – – – 30 –
ml/mw – – – – – – – – – – – – – 0.7 –
PL 72 71 74 72 58 66 63 63 61 66 56 46 53 – –
SL 142 144 142 117 128 125 120 115 126 98 – –
PA 160° 160° 177° – –
Table 1
Measurements (in millimetres and degrees) and ratios of described trackways
from the Na’ur Formation (Upper Cretaceous, Cenomanian) of Jordan.
* – average value based on all imprints in the trackway.
Abbreviations: pl – pes length; pw – pes width; ml – manus length; mw – manus width;
PL – pace length; SL – stride length; PA – pace angulation.

334 H. Klein et al.
Fig. 2. Overview of lowermost track surface (track level 1). A. Photograph showing the Jabal Safaha locality out-
crop with its limestone-marl succession of the Na’ur Formation (Upper Cretaceous, Cenomanian) and exposed footprint
surface with theropod trackways (bottom). Metrestick for scale = 200 cm. B. Photograph showing theropod trackway
SPMN-JTP 1 (cf. Picunichnus). Metrestick for scale = 200 cm. C. Interpretive outline drawing of trackway in B.

335First Upper CretaCeoUs dinosaUr traCk
Fig. 3. Photogrammetric 3D models of footprints described here from the Na’ur Formation of Jordan. A–D. Two theropod tracks
cf. Picunichnus from trackway SPMN-JTP 1 as orthophotograph (left; A, C) and inclination plot (right; B, D). E–G. Elongate theropod
track from trackway SPMN-JTP 3 as orthophoto (left; E), ambient occlusion image (center; F) and inclination plot (right; G); notice ex-
tensive metatarsal impression. H–J. Sauropod pes-manus set (top) and pes imprint (bottom) SPMN-JTP 6 as orthophotograph (left; H),
ambient occlusion image (center; I) and false-colour depth map (right; J).

336 H. Klein et al.
Fig. 4. Photographs showing details of cf. Picunichnus tracks from trackway SPMN-JTP 1 and SPMN-JTP 2 (A–D). Scale sections of
metrestick in D = 10 cm.
II–IV ~ 65°. Posterior end of tracks with broad and round-
ed metatarsal area that can be rather short or elongated
depending on the substrate. Trackways with average val-
ues for pace lengths being 72 cm, for stride lengths 142 cm
and for pace angulation 160°. The degree of morphological
preservation is “2” (Marchetti et al., 2019).
Discussion. The overall shape of the imprints with robust
digit traces, low mesaxony (digit III anterior projection com-
pared to that of digits II and IV), the broad rounded metatar-
sal region, and digit II being shorter and sometimes medial-
ly directed, are similar to Picunichnus described originally
by Calvo (1991) from mid-Cretaceous deposits of Argentina

337First Upper CretaCeoUs dinosaUr traCk
and recently revisited by Melchor et al. (2019). In their di-
agnosis, Melchor et al. (2019) list further characters such as
the distinct pad impressions and an occasional hallux trace.
Both are not observed in the tracks from Jordan. The lack or
indistinct appearance of the former could be a preservation-
al effect, however, a hallux trace might be expected at least
in some imprints that are up to 5 cm deep. Furthermore,
the robust appearance of digit traces could also be enhanced
by the soft substrate. Because of these uncertainties, we re-
frain from assigning the material from Jordan to a distinct
ichnotaxon; instead, we propose a more tentative attribution
to cf. Picunichnus based on the above-mentioned similar-
ities in morphology. Tridactyl theropod tracks are in need
of revision (see Castanera et al., 2016a and Melchor et al.,
2019 for discussion).
Elongate theropod tracks
Material. Trackway SPMN-JTP 3 with 8 successive pes
imprints; trackway SPMN-JTP 4 with 5 successive pes
imprints; trackway SPMN-JTP 5 with 3 successive pes im-
prints; several indistinct trackways and isolated imprints,
uncatalogued; all on the same surface at a slightly higher
level relative to the main surface (Figs 3E–G, 5; Table 1).
Description. Tridactyl, plantigrade pes imprints, up to 36 cm
in overall length (including the impression of the metatar-
sals) and 11 cm in width, with very slender digits that can
be straight or curved and terminate in sharp ends. Middle
digit by far longest, II and III short and with large divarica-
tion angle, > 80°, occasionally > 90°. No hallux impression
was observed. In particular, trackway SPMN-JTP 3 has ex-
tensive metatarsal impressions, reaching about half of the
overall pes length. These consist of a broader distal part
connected to the triangular digital area (4–5 cm in width),
proximally followed by a narrow portion (2 cm in width)
and ending in a broad rounded “heel” (4 cm in width). The
trackway pattern is very narrow with high pace angulation
between 160° and 177°. Pace lengths range between 56 cm
and 66 cm and stride lengths are between 115 and 128 cm.
Imprints of trackways SPMN-JTP 4 and SPMN-JTP 5 have
a similar morphology of the portion with digits II, III, IV
but have only a relatively short broad “heel,” which in some
tracks can be missing.
SPMN-JTP 5 shows a pes length of 24 cm and a pes
width of 10 cm. The trackway has pace lengths of 46 cm and
53 cm and a stride length of 98 cm. The degree of morpho-
logical preservation is “2” (Marchetti et al., 2019).
Discussion. Tridactyl footprints with more or less exten-
sive metatarsal impressions have been documented from
numerous sites (e.g., Kuban, 1989; Lockley et al., 2003,
2006; Milàn et al., 2008; Milner et al., 2009; Wilson et al.,
2009; Farlow et al., 2012; Perez-Lorente, 2015; Xing et al.,
2015a; Citton et al., 2015; Romano and Citton, 2017).
They have been explained by these authors as the result of:
1) walking in a plantigrade manner; 2) soft substrate, where
metatarsals were registered because the foot was deep-
ly sinking in; 3) sitting (crouching or squatting) position,
sometimes even leaving a mark of the ischium or the tail,
when the left and right foot was impressed side by side. This
is documented from both ornithischian and theropod tracks
(Olsen and Rainforth, 2003; Milner et al., 2009; Wilson et
al., 2009). In particular, some ornithischian tracks, such as
the Jurassic ichnogenera Anomoepus and Moyenisauropus,
commonly show impressions of the metatarsals, pedal digit
I (hallux) and, additionally, an imprint of the manus while
resting (Ellenberger, 1974; Gierliński et al., 2009; Wilson
et al., 2009). In walking trackways of these ichnotaxa of-
ten only digits II III, IV are registered, and an impression
of the metatarsals is missing. Nevertheless, there are ex-
amples that show metatarsal impressions while performing
a wider gauge (Wilson et al., 2009). In theropod trackways
“resting positions” are rare but well known (Milner et al.,
2009). Morphotype 2 trackways from the Na’ur Formation
of Jordan, however, indicate a normal walking progression
without any irregularities that might support a peculiar gait
on an unstable and slippery substrate. They are very narrow
and the pes imprints are equally spaced, although the stride
and pace are relatively short compared to Morphotype 1.
The possibility that at least some dinosaurs occasionally
walked in a plantigrade manner, is widely accepted and also
cannot be excluded for the makers of the Jordanian track-
ways (Kuban, 1989; Wilson et al., 2009). Another expla-
nation is considered in the following. Imprints are not very
deep and digit traces are mostly thin, anteriorly elongated
and lack distinct phalangeal pad impressions. Their shape
resembles penetrative tracks (Milàn and Bromley, 2006;
Falkingham and Gatesy, 2019; Falkingham et al., 2020;
Turner et al., 2020) that are registered on multiple layers
when digits are penetrating downwards into the substrate.
These are different from transmitted undertracks and char-
acteristically often display very thin digits, a phenomenon
that may partly be related to mud-collapse. The presence
of penetrative tracks could also explain the registration of
metatarsals that, together with the digits, penetrated several
layers, leaving their traces at different levels of the substrate.
In a strict sense, penetrative tracks are “true tracks,” because
the substrate was in direct contact with the foot. The thero-
pod that left the Jordanian trackways may have walked over
a relatively soft substrate, sunk in more deeply, registering
the three digits and the metapodium on several layers, one of
them exposed on the examined surface. More intensive inves-
tigation is needed of the sedimentology and preservation of
these trackways during our future eldwork at the site.
Ichnotaxonomically we refrain here from a concrete as-
signment. Presently, it can’t be excluded that the elongate
theropod tracks and cf. Picunichnus represent the same
ichnotaxon, the former being an extramorphological (sub-
strate- and/or gait-related) variation. Similarities of both
morphotypes with some variation in the metatarsal area may
support this.
Sauropod tracks
Material. SPMN-JTP 6, pes-manus set and associated pes
from horizon higher than theropod track levels (Figs 3H–J,
6A; Table 1).
Description. The right set consists of an oval pes imprint,
40 cm in length and 37 cm in width, and a half-moon to
kidney-shaped manus imprint anterior to the pes imprint,
which is 20 cm in length and 30 cm in width. The associated

338 H. Klein et al.
Fig. 5. Theropod trackway SPMN-JTP 3 with elongate footprints from track level 2. A. Photograph showing surface with track-
way consisting of 8 pes imprints. B. Detail of trackway in A, with arrows pointing to isolated imprints. C–D. Interpretive outline
drawings with part of the trackway and detail. Numbers correspond to the position in different images.

339First Upper CretaCeoUs dinosaUr traCk
Fig. 6. Sauropod and ornithopod tracks. A. Photograph with detail of sauropod pes-manus set SPMN-JTP 6 from track level 4.
B, C. Ornithopod pes imprint SPMN-JTP 7 from track level 3 as a photograph and interpretive outline drawing.
left pes imprint is of similar shape and size. The degree of
morphological preservation is “1” (Marchetti et al., 2019).
Discussion. The oval shape of the pes and the half-moon or
kidney-shaped manus is characteristic of sauropod tracks.
The position and rotation of the manus relative to the pes
suggests a right set, with the manus showing a stronger out-
ward rotation relative to the pes.
Possibly the associated left pes imprint belongs to the
same trackway and represents the preceding trace. Outward
rotation of pes imprints in sauropod trackways is highly
variable and can be very large (Lallensack et al., 2018).
Unfortunately, no complete trackway is known from this
surface. Moreover, the imprints lack distinct digit traces.
The laterally extended (“digit-like”) narrow portion of the
pes imprint is rather an artefact of the soft substrate. It is
difcult to compare these tracks with known sauropod ich-
notaxa. The heteropody is similar to Brontopodus (Farlow
et al., 1989; Lockley et al., 1994). This ichnogenus shows
low heteropody (manus relatively large compared to the
pes), while Parabrontopodus has generally high heteropo-
dy (manus relatively small compared to the pes; Lockley
et al., 1994). However, the kidney-shaped manus imprint is
different from that of Brontopodus, which is rather horse-
shoe-shaped (Castanera et al., 2016). There is a strong
resemblance of the specimen from Jordan with the ichno-
genus Sauropodichnus (Calvo, 1991; Calvo and Rivera,
2018) from the Candeleros Formation (Upper Cretaceous,
Cenomanian). This concerns the kidney-shaped manus im-
print and the subtriangular pes imprint. More complete ma-
terial is needed for a denitive assignment.
Ornithopod track
Material. SPMN-JTP 7, isolated pes imprint from the horizon
above the level with sauropod tracks (Fig. 6B, C; Table 1).
Description. The isolated tridactyl pes imprint SPMN-JTP 7
is wider than long, about 18 cm in length and 20 cm in
width. It shows broad digits with thick and rounded pads

340 H. Klein et al.
and indistinct blunt claw traces. The posterior margin is
slightly incomplete. The degree of morphological preserva-
tion is “1.5” (Marchetti et al., 2019).
Discussion. The overall broad symmetrical shape of the
imprint with the relatively short and wide middle digit III is
characteristic of ornithopod tracks such as Iguanodontipus
or Caririchnium (Lucas et al., 2011; Díaz-Martínez et al.,
2015). However, the small size together with the extreme-
ly short, subequal digits and the pes being wider than long
strongly resembles ornithopod tracks described by Kim
et al. (2009) from the Lower Cretaceous of Korea and as-
signed to Ornithopodichnus. After Díaz-Martínez et al.
(2015) Ornithopodichnus should be considered a nomen
dubium. Therefore, we refrain from using the name here for
any formal assignment. More generally, the features of the
Jordanian material, such as the broad, mesaxonic and overall
subsymmetrical shape, and the presence of large pads in the
digits, are diagnostic of the ichnofamily Iguanodontipodidae
Vialov (sensu Díaz-Martínez et al., 2015) and suggest an
attribution to the latter. Similar features can also be ob-
served in ornithopod footprints described from the Lower
Cretaceous of Palestine (Owais, 2020).
The lack of a manus can indicate bipedal progression or
a preservational effect. Nevertheless, the isolated specimen
does not allow a concrete assignment and further material is
needed for a better evaluation.
IMPLICATIONS FOR
PALAEOENVIRONMENT
The discovery of dinosaur footprints in the Na’ur
Formation, a unit dominated by marine transgressions with
carbonate rocks and characteristic marine body fossil as-
semblages, suggests uctuating water levels when surfaces
were subaerially exposed and dinosaurs frequented the shore
searching for food. This indicates a typical tidal at environ-
ment, possibly intertidal, with a high potential for footprint
preservation. The dinosaur community that roamed the area
consisted of small to medium-sized theropods, small sauro-
pods and small ornithopods. Thus far no footprints of large
forms have been found.
The represented groups coarsely match those known
from skeletal dinosaur fossils found in the Cretaceous
of the Middle East. Theropod skeletal remains have been
described from the Upper Cretaceous of Syria, Oman and
Saudi Arabia (Hooijer et al., 1968; Schulp et al., 2000; Kear
et al., 2013). Brachiosaurid, titanosaurian and indetermi-
nate sauropod remains are known from the Lower–Upper
Cretaceous deposits of Lebanon, Jordan, Oman and Saudi
Arabia (Buffetaut et al., 2006; Wilson et al., 2006; Schulp et
al., 2008b; Kear et al., 2013), and ornithopod skeletal fossils
are known from the Upper Cretaceous (Maastrichtian) of
Jordan and Oman (Martill et al., 1996; Schulp et al., 2008b).
The footprint assemblage described from Jordan is char-
acterized by its higher diversity, if compared to formerly
known tracksites from this Middle East region (Avnimelech,
1962a, b; Gèze et al., 2016; Owais, 2020), with the co-oc-
currence of trackways left by theropods, sauropods and or-
nithopods. This implies a ourishing habitat with different
carnivorous and herbivorous dinosaurs, extending along
the Tethys coast and tidal ats that formed the Na’ur
Formation environment.
CONCLUSIONS
The footprint assemblage from the Na’ur Formation
(Upper Cretaceous, Cenomanian) of Jordan suggests the
presence of a dinosaur community composed of small to
mid-sized theropods, sauropods and ornithopods. While the
latter two are documented by scarce isolated tracks only,
theropods are abundant with two different tridactyl mor-
photypes along several trackways: 1) Morphotype 1 dis-
plays a prominent, broad proximal part that represents the
distal metatarsal region and is tentatively assigned here to
cf. Picunichnus based on several morphological similari-
ties; 2) Morphotype 2 shows extensive, narrow metatarsal
impressions and digits are of a very thin, elongate shape,
resembling penetrative tracks that have been dened more
recently based on computer simulations (Falkingham and
Gatesy, 2019; Falkingham et al., 2020; Turner et al., 2020).
If these morphotypes refer to different ichnotaxa and track-
maker groups, or if they are the result of extramorphologi-
cal variation, is unclear. No ichnotaxonomic assignment is
given here to the sauropod and ornithopod tracks, because
these are isolated imprints with more general features.
Future prospecting should include the Albian Kurnub
Group and a re-location of dinosaur footprints mentioned
in former papers. It will be important to nd out if there are
differences to the assemblage from the Na′ur Formation and
possible faunal changes across the Lower-Upper Cretaceous
boundary.
Acknowledgments
The authors thank Spencer G. Lucas and Diego Castanera for
their constructive reviews and comments that improved the manu-
script. Abdalla Abu Hamad from the University of Jordan, Amman
is thanked for eld work support.
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