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Ornithopod tracks, theropod with trail trace, and bird track from the Cretaceous of Korea

Ben Creisler

A new paper:

Jeong Yul Kim, Martin G. Lockley & Hee Young Chun (2016)
New dinosaur tracks from the Lower Cretaceous
(Valanginian-Hauterivian) Saniri Formation of Yeongdong area, central
Korea: Implications for quadrupedal ornithopod locomotion.
Cretaceous Research 61: 5–16

Newly discovered tracks of a large quadrupedal ornithopod and a
theropod with trail trace, and a bird track from the Cretaceous Saniri
Formation of Yeongdong area are described. One ornithopod trackway is
very unusual in having large (length width ∼15 and >15 cm
respectively) clover-leaf-like manus tracks situated anteromedial to
the pes tracks with atypical negative, inward rotation of 45°.
Ornithopod pes tracks are quadripartite with three separated,
elongate-oval, nearly parallel sided, wide digit impressions and a
separate suboval heel impression (mean length and width about 41 and
36 cm respectively: l/w ratio 1.13). Manus track morphotypes are a
clover-leaf-shaped configuration of three digit impressions,
representing digits II–IV, in triangular configuration and registered
just in front of (anteromedial to) pes track digits II and III. The
pes morphotype is typical of Caririchnium, but the manus morphotype is
quite distinct from previously described ichnotaxa, thus justifying a
new ichnotaxon: Caririchnium yeondongensis ichnosp. nov., probably
representing a facultatively-quadrupedal Iguanodon-like trackmaker.

Theropod tracks are composed of three tapered pes digit impressions
with interdigital angles between digits II and IV 45°. Length and
width about 22.8 cm and 15.5 cm, respectively. Pace, stride, and pace
angles are about 51 cm, 101 cm, and 170°, respectively. Theropod
tracks are characteristically associated with a nearly continuous tail
trace, which is up to 360 cm in length, 4.5 to 6 cm in width, and
broad “U” shaped in cross section. Expulsion rims and dragging striae
occur intermittently. In addition, dinosaur skin impressions, poorly
preserved large sauropod tracks, a bird track, invertebrate and plant
fossils are found from the lake margin deposits also containing rain
drop impressions and desiccation cracks. Dinosaur tracks of the
Yeongdong area represent the oldest (Valanginian-Hauterivian) dinosaur
tracks of Korea.