Exploring the preservation of a parasitic trace in decapod crustaceans using finite elements analysis

The fossil record of parasitism is poorly understood, due largely to the scarcity of strong fossil evidence of parasites. Understanding the dynamics of preservation for fossil parasitic evidence is critical to contextualizing the fossil record of parasitism. Here, we present the first use of X-ray computed tomography (CT) scanning and finite elements analysis (FEA) to analyze the impact of a parasite-induced fossil trace on host preservation. Seven fossil and modern decapod crustacean specimens with branchial swellings attributed to an epicaridean isopod parasite were CT scanned and examined with FEA to assess differences in the magnitude and distribution of stress between normal and swollen branchial chambers. The results of the FEA show highly localized stress peaks in reaction to point forces, with higher peak stress on the swollen branchial chamber for all specimens, suggesting a possible shape-related decrease in the preservation potential of these parasitic swellings. Broader appl..., Specimen acquisition
            Seven specimens of recent and fossil decapod crustacean specimens with swellings attributable to K. crusta were studied through institutional loans: three Recent specimens of Munida valida from the Gulf of Mexico preserved in 70% ethanol (Fig 1 A-C), three complete fossil specimens of Macroacaena rosenkrantzi in siderite concretions from the Maastrichtian of Greenland, from a site referred to as the oyster-ammonite locality (Fig 1 D-F), and one isolated fossil carapace of Panopeus nanus in lower Miocene limestone from the Duncans Quarry, Trelawny Parish, Jamaica (FLMNH-IP locality XJ015) (Fig 1 G). These specimens were studied through institutional loans from Texas A&M University in College Station, Texas, USA (TAMU), the Natural History Museum of Denmark in Copenhagen, Denmark (NHMD) stored in the Type and Illustrated Paleontology Collection, and the University of Florida, Florida Museum of Natural History, Invertebrate Paleontology in Gainesville, ..., , # Exploring the preservation of a parasitic trace in decapod crustaceans using finite elements analysis

[https://doi.org/10.5061/dryad.8cz8w9gz4](https://doi.org/10.5061/dryad.8cz8w9gz4)

## Description of the data and file structure

The associated CSV file contains unordered von Mises stress values associated with vertices from finite elements analysis performed on healthy and swollen (ichnotaxon *Kanthyloma crusta*) branchial chambers of CT-scanned fossil and modern decapod crustaceans. See dataset and dataset description for information about the specimens. All values are von Mises stress in pascals. For more information, see the associated article.