ARTHROPOD TERRESTRIALIZATION: NEW ICHNOLOGICAL DATA FROM THE LATE SILURIAN CLAM BANK FORMATION, NEWFOUNDLAND

Late Silurian arthropod trackways, back-filled burrows and unusual foraging traces, from the Clam Bank Formation in Newfoundland, eastern Canada, bolster evidence suggesting that arthropods were already exploiting terrestrial environments by the Late Silurian. Among these trace fossils are three Diplichnites trackways, which were produced by myriapods. Based on biomechanical formulae of arthropod locomotion and theoretical bauplans based on computational and functional analyses, probable producers (e.g. eoarthropleurid and kampecarid myriapods) are assigned to these trackways.

Additionally, the Clam Bank Formation has recently produced a Beaconites burrow, demonstrating an adaptive burrowing/aestivation strategy amongst these arthropods to cope with the strenuous terrestrial landscape. Furthermore, a distinct array of scratch-bundles, which resembles Striatichnium (known previously only from the Rotliengendes of Germany), extends the stratigraphic range of this rare ichnogenus, and provides convincing evidence for foraging behavior in a myriapod or euthycarcinoid producer.