New ichnological clues shed light on the Permian tetrapod fauna from “Torre del Porticciolo” (NW Sardinia, Italy)

PAOLO CITTON; MARCO ROMANO; EVA SACCHI; CIPRIANI ANGELO; MAGANUCO, SIMONE; AUSONIO RONCHI; INNAMORATI GIULIA; ZUCCARI COSTANTINO; CARATELLI MARTINA; MANUCCI FABIO; NICOSIA, UMBERTO

Virtual

Congreso; 4th Palaeontological Virtual Congress; 2023

Ancient continental deposits bearing skeletal and ichnological tetrapod remains provide complementary information that improve our understanding of faunal composition in deep time terrestrial ecosystems. A suggestive case is represented by the uppermost Cisuralian-lowermost Guadalupian Cala del Vino Formation (Sardinia, Italy). Two ‘pelycosaurs’ (medium- to large- and giant-sized) and footprints referred to Merifontichnus isp. (medium-sized producer) were reported from silty-sandy sediments at approximately the same stratigraphic level within this unit. Newly recovered ichnological material enables corroborating the occurrence of Merifontichnus isp. and adding more footprint morphologies. The new record consists of five trackways and a plethora of traces (as overtracks, true tracks and undertracks), most of which were left by small-sized producers crossing a puddle that was filling up by muddy sediments, allowing the preservation of traces. A first morphology, found in association with raindrop prints, is represented by plantigrade, tetradactyl, wider than long footprints, with stout and rounded digit tip imprints, referred to Limnopus isp. A second morphology includes negatively rotated, longer than wide, tetradactyl pedal and pentadactyl manual prints, displaying slender and straight digit traces, referred to Hyloidichnus isp. A third morphology is represented by didactyl to tetradactyl pedal and manual prints with slender and curved digit traces referred to Dromopus isp. The new track record highlights different preservational demands for differently sized body- and ichnofossils. It adds tiny to medium-sized tetrapods, among which most likely temnospondyls, captorhinids, areoscelids and synapsids, to the late Cisuralian-early Guadalupian terrestrial palaeofauna of Sardinia, spurring further comparison with penecontemporaneous ecosystems across Pangaea.