Late Paleozoic larval paleobiology and evolutionary dynamics inferred from molluscs of the Buckhorn Asphalt and other lagerstätten

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Many important paleobiological questions can only be solved by the analysis of exceptionally wellpreserved fossils such as the molluscs (especially gastropods) from the Pennsylvanian Buckhorn Asphalt (Oklahoma, USA). This fossil lagerstätte contains by far the best preserved Paleozoic mollusc material including larval shells, original shell mineralogy and microstructures. Mollusc shells reflect ontogenetic change to a high degree. Paleozoic early ontogenetic shells including larval shells are rarely preserved and have been used for taxonomic purposes only. However, the information content of early ontogenetic shells is much higher. The abundance of gastropod larval shells with planktotrophic larval development forms a proxy for ancient primary production even if direct fossil record of phytoplankton is lacking as is the case during the enigmatic Late Paleozoic ¿Phytoplankton Blackout¿. We want to quantify the proportion of planktotrophic mollusc species from the Buckhorn Asphalt and other sites with exceptional preservation as evidence for primary production during the Carboniferous. This will be an important step towards the reconstruction of Late Paleozoic food webs, paleocommunities, and paleodiversity. We are aware that planktotrophic gastropod larval shells may or may not resemble adult shells within the same individual. Therefore, we want to test the activity of heterochrony through a comparative morphospace analysis of larval and adult shells. Heterochrony is one of the most discussed evolutionary processes and gastropods belong to the best objects to study these processes in deep time.