Data from: A 3D anatomical atlas of appendage musculature in the chelicerate arthropod Limulus polyphemus

Limulus polyphemus, an archetypal chelicerate taxon, has interested both
biological and paleontological researchers due to its unique suite of
anatomical features and as a useful modern analogue for fossil arthropod
groups. To assist the study and documentation of this iconic taxon, we
present a 3D atlas on the appendage musculature, with specific focus on
the muscles of the cephalothoracic appendages. As L. polyphemus appendage
musculature has been the focus of extensive study, depicting the muscles
in 3D will facilitate a more complete understanding thereof for future
researchers. A large museum specimen was CT scanned to illustrate the
major exoskeletal features of L. polyphemus. Micro-CT scans of
iodine-stained appendages from fresh, non-museum specimens were digitally
dissected to interactively depict appendage sections and muscles. This
study has revealed the presence of two new muscles: one within the pushing
leg, located dorsally relative to all other patella muscles, and the other
within the male pedipalp, located in the modified tibiotarsus. This atlas
increases accessibility to important internal and external morphological
features of L. polyphemus and reduces the need for destructive fresh
tissue dissection of specimens. Scanning, digitally dissecting, and
documenting taxa in 3D is a pivotal step towards creating permanent
digital records of life on Earth.