Novel discovery of lamellar papillae on the grooming organ in Synsphyronus (Garypidae: Pseudoscorpiones)

The chelicerae, the first pair of appendages in Chelicerata, exhibit morphological and functional variation across arachnid orders. The two-segmented chelicerae of pseudoscorpions serve multiple functions including grooming, courtship, and grasping prey. Scanning electron microscopy was used to investigate structures found on the chelicera; the serrulae interiores and exteriores, grooming organs, were given special attention. Functional analogies were made between the cheliceral structures documented in pseudoscorpions and those found in other arthropods. The novel discovery of vestitural papillae and a patch of elongate papillae on the serrula exterior are reported. The focal taxon for the study is Synsphyronus (Garypidae), an Australasian genus.

► Chelicerae of pseudoscorpions were investigated using scanning electron microscopy.
► Exteriors and interiors serrulae, grooming organs on the chelicerae, were imaged.
► Novel discovery of lamellar papillae on the serrula exterior.