Grallator Hitchcock, 1858

Niedźwiedzki, Grzegorz, 2011, A Late Triassic dinosaur-dominated ichnofauna from the Tomanová Formation of the Tatra Mountains, Central Europe, Acta Palaeontologica Polonica 56 (2), pp. 291-300 : 295

Ichnogenus Grallator Hitchcock, 1858

Type species: Grallator parallelus Hitchcock, 1858 ; South Hadley , Massachusetts, USA, Portland Formation, Lower Jurassic .

cf. Grallator isp.

Fig. 3A .

Description.— One specimen of this ichnogenus preserved as natural cast was found (field observation from Czerwone Żlebki). Grallator is the ichnogeneric name applied to relatively small (generally <15 cm long pes) tridactyl tracks of functionally bipedal dinosaurs from the Late Triassic and Early–Middle Jurassic ( Olsen et al. 1998; Clark et al. 2004). The pes is narrow, tulip−shaped and digit III projects far anteriorly relative to digits II and IV, which are rather sub−equal in length. The single specimen shows all these characteristics. The angle between the digits II and III is 9 °, while the angle between the digits III and IV is 18 °.

Remarks.— Grallator tracks are very common in Upper Triassic and Lower Jurassic strata (e.g., Lockley and Hunt 1995; Olsen et al. 1998; Gaston et al. 2003). They are found in the United States, Canada, Europe, Australia and China but are most abundant on the east coast of North America, especially the Upper Triassic and lowermost Jurassic formations of the northern part of the Newark Supergroup ( Haubold 1984; Olsen et al. 1998).

Figures

Fig. 3. Tridactyl tracks (pes prints) of small to medium sized theropod dinosaurs. A. cf. Grallator isp. B–E Anchisauripus isp. A, E. Specimens from Czerwone Żlebki site, Tomanová Formation (?late Norian–Rhaetian), Poland. B–D. Specimens from Červený Ŭplaz site, Tomanová Formation (?late Norian–Rhaetian), Slovakia. A, C, E. Specimens left in field.B. Specimen Z 14 297 housed at Slovak National Museum, Bratislava, Slovakia. D. Specimen deposited at Tatra Mountains National Park, Zakopane, Poland. Photographs (A1–E1) and drawings (A2–E2). Scale bars 5 cm.