Exploring hemipteroid morphology with microCT

The Hemipteroid Tree of Life project aims to use both phylogenomic and morphological data to resolve the evolutionary relationships among major lineages of hemipteroid insects (Psocodea, Thysanura, and Hemiptera) at and above the family level. Along with using conventional microscopy methods for the morphological component of this task, it is possible to use micro-computed tomography (microCT) to confirm homologies and fill gaps in knowledge of internal anatomy. The non-invasive nature of CT scanning allows specimens to be retained in collections after their use, which means internal systems and soft tissue are retained in their natural configuration and can be made visible in reconstructions. This can assist in investigating anatomical structures that are lost, damaged or appear cryptic in conventional methods of preparation and visualization, as well as finding novel character states that were previously overlooked.

Recent work has allowed for refinement of preparation and scanning techniques to maximize the amount of data that can be captured from individual scans. In this project, representatives from major groups of Thysanura and Hemiptera are visualized using an XRadia BioCT scanner, with a goal of describing internal characters from the digestive tract as well as visualizing the brain and major ganglia. In doing so, it evaluates the reliability of microCT as a form of data acquisition for morphological phylogenetics across a diverse range of taxa and demonstrates the potential phylogenetic significance of internal characters. Included in the presentation will be several images of the internal anatomy visualized from these scans.