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.Supplementary Figure 1Fig. S1: 3D interactive model of the complete Limulus polyphemus specimen, as modelled from CT-scanning.Fig._S1.pdfSupplementary Figure 2Fig. S2: 3D interactive model of the Limulus polyphemus chelicera, as modelled from iodine staining and micro-CT-scanning.Fig._S2.pdfSupplementary Figure 3Fig. S3: 3D interactive model of the Limulus polyphemus walking leg, as modelled from iodine staining and micro-CT-scanning.Fig._S3.pdfSupplementary Figure 4Fig. S4: 3D interactive model of the Limulus polyphemus male pedipalp, as modelled from iodine staining and micro-CT-scanning.Fig._S4.pdfSupplementary figure 5Fig. S5: 3D interactive model of the Limulus polyphemus pushing leg, as modelled from iodine staining and micro-CT-scanning.Fig._S5.pdfSupplementary Figure 6Fig. S6: 3D interactive model of the Limulus polyphemus chilaria, as modelled from iodine staining and micro-CT-scanning.Fig._S6.pdfSupplementary Figure 7Fig. S7: 3D interactive model of the Limulus polyphemus genital operculum, as modelled from iodine staining and micro-CT-scanning.Fig._S7.pdfSupplementary Figure 8Fig. S8: 3D interactive model of the Limulus polyphemus gill operculum, as modelled from iodine staining and micro-CT-scanning.Fig._S8.pd