Digital Data in Biodiversity Research Conference

Each specimen housed within natural history collections represents a treasure trove of anatomical knowledge waiting to be uncovered. To reveal soft tissues inside fluid-preserved specimens, diffusible iodine-based contrast-enhanced CT (diceCT) is a commonly used method that involves staining specimens with an iodine solution, increasing the radiopacity of soft tissues so they can be imaged using X-ray CT. The recent diceCT effort at the Florida Museum of Natural history is one of the largest and most taxonomically broad soft tissue imaging efforts in the world, with over 200 datasets produced covering fishes, amphibians, reptiles, and mammals. As part of the openVertebrate (oVert) Thematic Collections Network, these datasets are freely available via MorphoSource for research, education, art, and other purposes. We have refined methods for the application of diceCT for natural history collections, and we explore best practices informed by recent work in the field. We present recommendations including predictions for staining duration, suggestions for optimal staining techniques, and recommendations for scanning and post-processing. As diceCT continues to be a widely employed method for non-destructively documenting the soft anatomy of alcohol-preserved museum specimens, we hope that these datasets and methods will contribute towards the growing stock of digital anatomy in online repositories.