Revisional notes on the Permian tetrapod ichnofauna from the Tiddas Basin, central Morocco

During the mid-1980s, structural geological field work in the up to 300 m thick red-bed sequence of the Permian Tiddas Basin, central Morocco, revealed the first occurrence of Palaeozoic tetrapod footprints in NW Africa. Preservational ambiguity of part of the few published trace fossils and resulting taxonomic inconsistency necessitate a long-needed reanalysis of the type locality. Based on 110 recently collected specimens the revised tetrapod ichnofauna of the study area comprises tracks of Batrachichnus Woodworth, 1900 — Limnopus Marsh, 1894, Amphisauropus Haubold, 1970, Dimetropus Romer and Price, 1940, Varanopus Moodie, 1929 — Hyloidichnus Gilmore, 1927, and Dromopus Marsh, 1894 which can be referred to small and medium-sized temnospondyl, seymouriamorph, basal synapsid (‘pelycosaur’), captorhinomorph, and araeoscelid trackmakers. This assemblage is interpreted to represent a late Early Permian (Artinskian–Kungurian) tetrapod ichnofauna. Due to the relative abundance of footprints assigned to semiaquatic tetrapods and sedimentological evidence for pronounced humid palaeoclimatic conditions we propose correlation of the track-bearing strata with the late Artinskian/early Kungurian wet phase. Regarding the quality, quantity, and peculiar diversity of its fossils, including the earliest record of seymouriamorph and advanced captorhinomorph tracks from the African continent, the Tiddas Basin could be of great importance for the reconstruction of late Early Permian terrestrial ecosystems in proximity to the interface of Euramerican and Gondwanan biotic provinces.