Walk 'n Jump: Associated Insect Walking and Landing Trace Fossils from the Early Permian of the Southern Alps

Abstract

ABSTRACTWe describe a compound trace fossil Stiaria cf. intermedia C Avolatichnium isp. from the lower Permian of Southern Alps (North Italy) and confidently attribute it to a wingless (apterygote) jumping insect producer belonging to the order Monura (Insecta: Archaeognatha). We discuss the common features linking the ichnogenera Avolatichnium, Rotterodichnium and Tonganoxichnus, and suggest a close affinity for their producers. Grounded on previous studies and on some exceptional features preserved in the described material, we provide a biomechanical model for jumping in Archaeognatha and hypothesize that Paleozoic Archaeognatha performed jumps with high vertical and very low horizontal component and only later acquired the ability to heighten the horizontal component of their jumps, therefore, becoming more efficient in propelling themselves far ahead as extant species do.