A new paper:
Mostafa Oukassou,Hendrik Klein, Abdelouahed Lagnaoui, Andrà CharriÃre, Hafid Saber, Gerard D. GierliÅski, Jens N. Lallensack, Abdelkbir Hminna, Ayoub Boumaalif, Ahmed Oussou & Driss Ouarhache (2019)
Polyonyx-like tracks from Middle-?Upper Jurassic red beds of Morocco: implications for sauropod communities on southern margins of Tethys.
Palaeogeography, Palaeoclimatology, Palaeoecology (advance online publication)
https://doi.org/10.1016/j.palaeo.2019.109394 https://www.sciencedirect.com/science/article/abs/pii/S0031018219306145
Highlights
Diverse dinosaur-dominated ichnofauna are reported from Jurassic red beds at Imilchil, Morocco.
We describe, in detail, a long sauropod trackway of Polyonyx type.
Ichnotaxonomy of Middle Jurassic-Early Cretaceous sauropod tracks is reviewed.
Findings improve knowledge of sauropods along the southern margin of the Tethys.
Abstract
A new dinosaur tracksite is reported from continental red beds of the Jurassic (Late Bathonian-?Callovian) Isli Formation along the northern flank of the AÃt Ali ou Ikkou Syncline of the Imilchil area, Central High Atlas, Morocco. The succession was deposited in a fluvio-lacustrine environment, and contains at least fourteen track-bearing levels. The diverse dinosaur-dominated ichnofauna includes the footprints of crocodylomorphs, pterosaurs, theropods, sauropods and ornithischians, together with numerous invertebrate traces. Here, we focus on a long sauropod trackway, which comprises nine consecutive manus-pes sets preserved as concave epireliefs. The low heteropody and asymmetry of manus prints with a large digit I (pollex) impression oriented medially, and a large triangular claw trace, which is posteriorly oriented, are characteristic of the ichnogenus Polyonyx. Different from typical Polyonyx is the narrow gauge pattern compared to the wide gauge observed in the type trackway from Portugal. Additional material from Morocco, similar to Polyonyx, comprises the trackway of a very small (?juvenile) individual found close to the main trackway, as well as a short trackway from a different locality in the Isli Formation. Our data from the Moroccan High Atlas indicates the presence of basal eusauropods in the Middle Jurassic-Early Cretaceous interval in the northwestern part of Gondwana for the first time, and suggests they inhabited a lacustrine paleoenvironment.