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Tracks of a large thyreophoran dinosaur from the Early Jurassic of Poland

June 1999
Acta Palaeontologica Polonica 44(2):231-234

Authors:

Państwowy Instytut Geologiczny

The origin of a large ornithischian track Moyenisauropus karaszevskii Gierlinski, 1991, from the Hettangian of the Holy Cross Mountains of Poland, needs reappraisal, Hitherto, this taxon was difficult to compare with any known Liassic ichnotaxon from the Northern Hemisphere. Its previous taxonomic assignment is controversial as well. M, karaszevskii has been previously considered as a track of some unknown earliest iguanodontian, despite the lack of a supporting osteological record nor phylogenetic inferences based on timing and evolutionary patterns in advanced ornithopods, Thus, a new interpretation is proposed: this footprint may fit the foot of a basal thyreophoran such as Scelidosaurus harrisonii Owen, 1861 or a more stegosaur-like form. Also, the problematic Early Jurassic tracks Moyenisauropus natator Ellenberger, 1974 and Anomoepus pienkovskii Gierlinski, 1991, appear to be intermediate forms between the basal ornithischian tracks of Anomoepus Hitchcock, 1848 and the early advanced thyreophoran track of M. karaszevskii.

A. Pes of Scelidosaurus harrisonii Owen, 1861 (from Owen 1863) superimposed (B) onto Moyenisauropus karaszevskii Gierliliski, 1991 from the late Hettangian of Gliniany Las, Poland (C). D-F. Computer-generated topographic maps of the M. karaszevskii, digitized by J.O. Farlow in 1995. The illustrated track owned by author; its plaster cast ZPAL z.p.R.1111 is housed in the Institute of Palaeobiology of the Polish Academy of Sciences.

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Am4

PAWE@mU@OGA

P@NMOEA

Vol.

44,

No.

pp.

231

234,

Warszawa,

1999

Brief

report

Tracks of

large thyreophoran dinosaur from

the

Early

Jurassic of Poland

GERARD

GIERL~SKI

The origin of a large ornithischian track

Moyenisauropus karaszevskii

Gierliiiski, 1991, from

the Hettangian of the Holy Cross Mountains of Poland, needs reappraisal. Hitherto, this taxon

was difficult to compare with any known Liassic ichnotaxon from the Northern Hemisphere.

Its

previous taxonomic assignment is controversial as well.

karaszevskii

has been previously

considered as a track of some unknown earliest iguanodontian, despite the lack of a supporting

osteological record nor phylogenetic inferences based on timing and evolutionary patterns in

advanced ornithopods. Thus, a new interpretation is proposed: this footprint may fit the foot of

a basal thyreophoran such as

Scelidosaurus harrisonii

Owen, 1861 or a more stegosaur

form. Also, the problematic Early Jurassic tracks

Moyenisauropus natator

Ellenberger, 1974

and

Anonoepus pienkovskii

Gierliiiski, 1991, appear to be intermediate forms between the

basal ornithischian tracks of

Anornoepus

Hitchcock, 1848 and the early advanced thyreo-

phoran track of

kuraszevskii.

The ichnogenus Moyenisauropus Ellenberger, 1974 has remained one of the most problematic

ichnotaxa among the Early Jurassic tridactylous tracks. Ellenberger (1974) erected the ichnogenus

Moyenisauropus to comprise eight ichnospecies of the Liassic ornithischian ichnites from Lesotho:

Moyenisauropus natator, M. minor, M. vermivorus,

dodai,

natatilis,

levicauda, M. longi

cauda and M. minimus. Subsequent authors considered Moyenisauropus as junior synonym of

Anomoepus Hitchcock, 1848 (Olsen

Galton 1984; Thulborn 1994). There are indeed no morpho

logical differences between Anomoepus and most ichnospecies of Moyenisauropus to distinguish

them at the ichnogeneric level. However, Moyenisauropus natator (the type ichnospecies of Moyeni

sauropus) is different from any anomoepodid tracks.

M. natator the length ratio (sensu Olsen et al.

1998) of digit

III/IV

equals 0.66, which is below the value typical for anomoepodid tracks. Such ra

tios measured in the pes of supposed Early Jurassic anomoepodid trackrnakers (Lesothosaurus,

Scutellosaurus, Heterodontosaurus) are never lower than 0.7, according to Olsen et al. (1998: table

3).

Moreover, M. natator demonstrates a feature unusual among Liassic tridactylous tracks: it has

only two phalangeal pads on digit

III.

This may have been caused either by having only two

phalangeal joints on that digit, or three joints, if the penultimate phalanx was so short that the two dis

tal joints correspond to one distal pad. As exemplified by lateral toes of extant Rhea americana

(Farlow

Chapman 1997: fig. 36.1 I), very short distal non

ungual phalanges of the iguanodontid

and scelidosaurid pedal digit

III

may have been covered by a single distal phalangeal pad on that

digit, actually corresponding to more than one terminal phalangeal joint.

Distinctive features of Moyenisauropus natator are even more expressed in Moyenisauropus

karaszevskii Gierlifiski, 1991 from the late Hettangian of Gliniany Las, Poland (Fig. 1C-F). The Pol

ish form is more robust, with phalangeal pads much wider than those of M. natator. The metatar

sal

phalangeal pads of M. karaszevskii are almost fused into a large swollen proximal pad, a so

called

heel pad. The track length reaches 25 cm, being markedly larger than anomoepodids, whose pedal

imprints are usually about 10 cm long. Thus, the size (pedal length about 20 cm) and shape of M.

natator seem to be morphologically intermediate between Anomoepus and

karaszevskii.

Brief report

Fig. 1.

Pes of Scelidosaurus harrisonii Owen, 1861 (from Owen 1863) superimposed

(B)

onto Moyeni

sauropus karaszevskii Gierliliski, 1991 from the late Hettangian of Gliniany Las, Poland

(C).

Com

puter

generated topographic maps of the M. karaszevskii, digitized

J.O. Farlow in 1995. The illustrated

track owned by author; its plaster cast ZPAL z.p.R.1111 is housed in the Institute of Palaeobiology of the Pol

ish Academy of Sciences.

ACTA PALAEONTOLOGICA POLONICA (44) (2) 233

M. karaszevskii has been previously considered as an ichnite of some unknown early iguano-

dontid (Gierliriski 1991). However, no Early Jurassic remains of such purported trackmaker are

known. New evidence pertaining to the identity of the M. karaszevskii trackmaker appeared with the

recent discovery of similar, if not conspecific, footprints from the Hettangian of Dordogne, France.

The French tracks led Le Loeuff et al. (1998, 1999) to conclude of a basal thyreophoran affinity for

their trackmaker. Their conclusion was mainly supported by the features preQcted for stegosaur

tracks. Contrary to the Polish bipedal trackway, the French one contains manual imprints, which re-

semble a manus impression of Stegopodus czerkasi Lockley

Hunt, 1998, a Late Jurassic track from

Utah attributed to a stegosaur.

However, the stegosaur

like affinity suggested for the French and Polish tracks is not the only

available interpretation. The presence of hallux imprints in these tracks is discrepant with the strictly

tridactyl pes of stegosaurs. The phalangeal pad formula 1

2-2

0 (metatarsal

phalangeal pads not

included in the count) of the tracks in question does not fit the stegosaurian foot pattern well (contra

Le Loeuff et al. 1999). The primitive stegosaurian phalangeal formula 0-2

Huayangosaurus

is reduced to 0

2-0 in the more advanced forms like Stegosaurus (Galton 1990). Thus, the

phalangeal pads, if they correspond to the phalangeal joints, constitute a formula 0- 1

0 for primi-

tive stegosaurs, and 0

1-1

1-0 for the advanced ones. So, conceivably, the advanced stegosaur foot

pattern might have produced an iguanodontid-like track, with single phalangeal pads on each toe (see

Bakker 1996).

In my opinion, the pedal morphology and the Hettangian age of both Polish and French tracks

speak in favor of a pre

stegosaurian trackmaker. The foot of the basal thyreophoran Scelidosaurus

harrisonii Owen, 1861 shows a phalangeal formula of 2-3

0 (Fig. 1A). Extremely short distal

phalanges of Scelidosaurus digit

I11

and

may have resulted in the reduction of pad numbers in

these digits. Consequently, a foot of Scelidosaurus superimposed onto the footprint of Moyeni-

sauropus karaszevskii, fits quite well (Fig. 1B). Alternatively, M. karaszevskii may represent pedal

morphology linking the scelidosaurid foot pattern with the derived stegosaurian pattern (with re

duced phalangeal count in digits I11 and IV). In this case, the Scelidosaurus foot would be expected

to produce a more anomoepodid

like track than the stubby moyenisauropodid one. Then, another

ichnotaxon from the Gliniany Las, Anomoepus pienkovskii Gierlinski, 1991, is worth mentioning

here. This unusual anomoepodid, with pedal digit ratios close to those of M. natator and the two

distal pads on the digit I11 almost fused, is another candidate for a track of scelidosaurid origin (an

idea considered by Gierliiiski 1995b). Differences between A. pienkovskii and M. karaszevskii may

represent either low

level taxonomic, or ontogenetic variation (A. pienkovskii is 14 cm long, while

M. karaszevskii reaches 25 cm; estimated length of a digitigrade footprint of S. harrisonii would be

intermediate between the two).

These data require a reappraisal of the interpretation of Otozoum Hitchcock, 1847 as a scelido-

saurid

like thyreophoran track (Gierlinski 1995a). Otozoum, characterized by three well developed

phalangeal pads on digit

111,

does not fit the above scenario, where the shortening of basal

thyreophoran phalanges is reflected in reduction of the number of digital nodes. As recently noted by

Martin Lockley (written communication 1998), Otozoum is marked by a highly segmented pattern of

the foot which is much more theropod

like than in any configuration seen

large ornithischian

tracks. Moreover, the Otozoum hallux is a little too long for Scelidosaurus (Gierliriski 1995a).

Finally, new comparisons (Olsen et al. 1998) of the digit length ratios of prosauropod feet with those

of Otozoum support its traditional attribution to prosauropod origin (e.g., Lull 1953; Haubold 197 1;

Lockley

Hunt 1995).

Additionally, the interpretation of Moyenisauropus karaszevskii as a scelidosaurid track suggests

occasionally bipedal gait in these thyreophorans. Moreover, if Le Loeuff et al. (1998,1999) are right

about the stegosaurian nature of the trackmaker, such an early stegosaurian might also walked

bipedally, as did possibly later forms. If so, tracks of later, at least facultatively bipedal, stegosaurs

would be difficult to discern from bipedal iguanodontian tracks (especially the most robust thick-

toed forms) in the Late Jurassic and Early Cretaceous track assemblages.

Brief report

References

Bakker, R.T. 1996. The real Jurassic Park: Dinosaurs and habitats at Como Bluff, Wyoming.

In:

M. Morales

(ed.), The Continental Jurassic.

Museum of Northern Arizona Bulletin

60,34-49.

Ellenberger, P. 1974. Contribution

la classification des Pistes de Vertkbrks du Trias: les types du

Stormberg d'Afrique du Sud (II).

Palaeovertebrata, Mhoire extraordinaire,

201.

Farlow, J.O.

Chapman, R.E. 1997. The scientific study of dinosaur footprints.

In:

J.O. Farlow

M.K.

Brett

Surman (eds),

The Complete Dinosaur,

5 19

553. Indiana University Press, Bloomington and In

dianapolis.

Galton, P.M. 1990. Stegosauria.

In:

D.B. Weisharnpel, P. Dodson,

H. Osm6lska (eds),

The Dinosauria,

435455. University of California Press, Berkeley.

Gierlifiski, G. 1991. New dinosaur ichnotaxa from the Early Jurassic of the Holy Cross Mountains, Poland.

Palaeogeography, Palaeoclimatology, Palaeoecology

85,137

148.

Gierlifiski, G. 1995a. Thyreophoran affinity of

Otozoum

tracks.

Przeglqd Geologiczny

43,123

125.

Gierliliski, G. 1995b. ~ladami polskich dinozaurbw [in Polish]. 88 pp. BGW, Warszawa.

Haubold, H. 1971. Ichnia Amphibiorum et Reptiliorum fossilium.

In:

0. Kuhn (ed.),

Encyclopedia of

Paleoherpetology

18, 1

124. Gustav Fisher Verlag, Stuttgart.

Hitchcock, E. 1847. Description of two new species of fossil footmarks found in Massachusetts and Con

necticut, or of the animal that made them.

American Journal of Science

4,4657.

Hitchcock, E. 1848.

attempt to discriminate and describe the animals that made the fossil footmarks of

the United States, and especially New England.

Memoirs of the American Academy ofArts and Sci

ence

3,129

256.

Le Loeuff, J., Lockley, M.G., Meyer, C.A.,

Petit, J.

P. 1998. Earliest tracks of Liassic basal thyreo-

phorans.

Journal of Vertebrate Paleontology

18, Appendix to 3,58-59A.

Le Loeuff, J., Lockley, M.G., Meyer, C.A.,

Petit, J.

P. 1999. Discovery of a thyreophoran trackway in the

Hettangian of central France.

Comptes Rdndues de l'Acad6mie des Sciences Paris, Sciences de la

terre et des planf?tes

328,215

219.

Lockley, M.G.

Hunt, A.P. 1995

Dinosaur Tracks and Other Fossil Footprints of the Western United

States.

338 pp. Columbia University Press, New York.

Lockley, M.G.

Hunt, A.P. 1998. A probable stegosaur track from the Morrison Formation of Utah.

Modem Geology

23,33 1

342.

Lull, R.S. Triassic life of the Connecticut Valley.

State of Conecticut, State Geological and Natural His

tory Survey Bulletin

81, 1

336.

Olsen, P.E.

Galton, P.M. 1984. A review of the reptile and amphibian assemblages from the Stormberg of

South Africa, with special emphasis on the footprints and the age of the Stormberg.

Palaeontologia

Afrzcana (Haughton Memorial Volume)

25, 87

1 10.

Olsen, P.E., Smith, J.B.,

Mc Donald, N.G. 1988. The material of the type species of the classic theropod

footprint genera

Eubrontes, Anchisauripus

and

Grallator

(Early Jurassic, Hartford and Deerfield bas

ins. Connecticut and Massachusetts, U.S.A.).

Journal of Vertebrate Paleontology

18,586

601.

Owen, R. 1861. A monograph of the fossil Reptilia of the Lias formations. Part I:

Scelidosaurus harrisonii.

Palaeontographical Society Monographs

13, 1

14.

Owen, R. 1863. A monograph of the fossil Reptilia of the Lias formations. Part 11:

Scelidosaurus ham'sonii

Owen of the Lower Lias.

Palaeontographical Society Monographs

14, 1

26.

Thulborn, R.A. 1994. Ornithopod dinosaur tracks from the Lower Jurassic of Queensland.

Alcheringa

18,247-258.

Gerard Gierliriski, Paristwowy Instytut Geologiczny, ul. Rakowiecka

975 Warszawa, Poland.

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Extensive and well-preserved tracksites in the coastally exposed Lower Cretaceous (Valanginian–Barremian) Broome Sandstone of the Dampier Peninsula provide almost the entire fossil record of dinosaurs from the western half of the Australian continent. Tracks near the town of Broome were described in the late 1960s as Megalosauropus broomensis and attributed to a medium-sized theropod trackmaker. Brief reports in the early 1990s suggested the occurrence of at least another nine types of tracks, referable to theropod, sauropod, ornithopod, and thyreophoran trackmakers, at scattered tracksites spread over more than 80 km of coastline north of Broome, potentially representing one of the world's most diverse dinosaurian ichnofaunas. More recently, it has been proposed that this number could be as high as 16 and that the sites are spread over more than 200 km. However, the only substantial research that has been published on these more recent discoveries is a preliminary study of the sauropod tracks and an account of the ways in which the heavy passage of sauropod trackmakers may have shaped the Dampier Peninsula's Early Cretaceous landscape. With the other types of dinosaurian tracks in the Broome Sandstone remaining undescribed, and the full extent and nature of the Dampier Peninsula's dinosaurian tracksites yet to be adequately addressed, the overall scientific significance of the ichnofauna has remained enigmatic. At the request of the area's Goolarabooloo Traditional Custodians, 400+ hours of ichnological survey work was undertaken from 2011 to 2016 on the 25 km stretch of coastline in the Yanijarri–Lurujarri section of the Dampier Peninsula, inclusive of the coastline at Walmadany (James Price Point). Forty-eight discrete dinosaurian tracksites were identified in this area, and thousands of tracks were examined and measured in situ and using three-dimensional photogrammetry. Tracksites were concentrated in three main areas along the coast: Yanijarri in the north, Walmadany in the middle, and Kardilakan–Jajal Buru in the south. Lithofacies analysis revealed 16 repeated facies types that occurred in three distinctive lithofacies associations, indicative of an environmental transgression between the distal fluvial to deltaic portions of a large braid plain, with migrating sand bodies and periodic sheet floods. The main dinosaurian track-bearing horizons seem to have been generated between periodic sheet floods that blanketed the preexisting sand bodies within the braid plain portion of a tidally influenced delta, with much of the original, gently undulating topography now preserved over large expanses of the present day intertidal reef system. Of the tracks examined, 150 could be identified and are assignable to a least eleven and possibly as many as 21 different track types: five different types of theropod tracks, at least six types of sauropod tracks, four types of ornithopod tracks, and six types of thyreophoran tracks. Eleven of these track types can formally be assigned or compared to existing or new ichnotaxa, whereas the remaining ten represent morphotypes that, although distinct, are currently too poorly represented to confidently assign to existing or new ichnotaxa. Among the ichnotaxa that we have recognized, only two (Megalosauropus broomensis and Wintonopus latomorum) belong to existing ichnotaxa, and two compare to existing ichnotaxa but display a suite of morphological features suggesting that they may be distinct in their own right and are therefore placed in open nomenclature. Six of the ichnotaxa that we have identified are new: one theropod ichnotaxon, Yangtzepus clarkei, ichnosp. nov.; one sauropod ichnotaxon, Oobardjidama foulkesi, ichnogen. et ichnosp. nov.; two ornithopod ichnotaxa, Wintonopus middletonae, ichnosp. nov., and Walmadanyichnus hunteri, ichnogen. et ichnosp. nov.; and two thyreophoran ichnotaxa, Garbina roeorum, ichnogen. et ichnosp. nov., and Luluichnus mueckei, ichnogen. et ichnosp. nov. The level of diversity of the main track types is comparable across areas where tracksites are concentrated: Kardilakan–Jajal Buru (12), Walmadany (11), and Yanijarri (10). The overall diversity of the dinosaurian ichnofauna of the Broome Sandstone in the Yanijarri–Lurujarri section of the Dampier Peninsula is unparalleled in Australia, and even globally. In addition to being the primary record of non-avian dinosaurs in the western half of Australia, this ichnofauna provides our only detailed glimpse of Australia's dinosaurian fauna during the first half of the Early Cretaceous. It indicates that the general composition of Australia's mid-Cretaceous dinosaurian fauna was already in place by the Valanginian–Barremian. Both sauropods and ornithopods were diverse and abundant, and thyreophorans were the only type of quadrupedal ornithischians. Important aspects of the fauna that are not seen in the Australian mid-Cretaceous body fossil record are the presence of stegosaurians, an overall higher diversity of thyreophorans and theropods, and the presence of large-bodied hadrosauroid-like ornithopods and very large-bodied sauropods. In many respects, these differences suggest a holdover from the Late Jurassic, when the majority of dinosaurian clades had a more cosmopolitan distribution prior to the fragmentation of Pangea. Although the record for the Lower Cretaceous of Gondwana is sparse, a similar mix of taxa occurs in the Barremian–lower Aptian La Amarga Formation of Argentina and the Berriasian–Hauterivian Kirkwood Formation of South Africa. The persistence of this fauna across the Jurassic-Cretaceous boundary in South America, Africa, and Australia might be characteristic of Gondwanan dinosaurian faunas more broadly. It suggests that the extinction event that affected Laurasian dinosaurian faunas across the Jurassic-Cretaceous boundary may not have been as extreme in Gondwana, and this difference may have foreshadowed the onset of Laurasian-Eurogondwanan provincialism. The disappearance of stegosaurians and the apparent drop in diversity of theropods by the mid-Cretaceous suggests that, similar to South America, Australia passed through a period of faunal turnover between the Valanginian and Aptian. -------- In: Society of Vertebrate Paleontology Memoir (Journal of Vertebrate Paleontology Vol. 36, supplement to 6, November 2016).

Type material of the type species of the classic theropod footprint genera Eubrontes, Anchisauripus, and Grallator (Early Jurassic, Hartford and Deerfield Basins, Connecticut and Massachusetts, U.S.A.)

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Sep 1998

The classic Early Jurassic age theropod footprints Eubrontes giganteus, Anchisauripus sillimani, and Grallator parallelus were established by Edward Hitchcock in 1836–1847 and are the type ichnospecies of their respective ichnogenera. We identify, describe, and figure the type specimens in detail for the first time since they were named. We also figure and describe the other elements of the type series as well as specimens mistakenly thought to be the types. All of the tracks come from cyclical lacustrine and marginal lacustrine to fluvial strata from an interval spanning about one million years in the Early Jurassic age Meriden and Agawam groups of the Hartford and Deerfield basins of Connecticut and Massachusetts. Based on osteometric comparisons with skeletal material, these three ichnospecies were most likely made by theropod dinosaurs, as usually assumed. Although treated here as distinct ichnogenera, it is possible that their major proportional differences derive from allometric growth with individuals of several related species in one genus or even within one species of trackmaker. The rigorous establishment of these classic ichnological taxa forms a basis for more wide ranging studies of theropod diversity in the early Mesozoic.

Type material of the type species of the classic theropod footprint genera Eubrontes, Anchisauripus and Grallator Early Jurassic, Hartford and Deerfield basins, Connecticut and Massachusetts, USA

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