In depth
Walliserops is a unique type of trilobite with it having a trident on its head. It also had spines all around it but one common similarity with all Walliserops species that they all have the signature trident on there head.
Walliserops shows sexual selection through combat with jousting with the trident they have. Walliserops has the earliest know from of sexual combat. Walliserops used there trident like some modern day beetles use there horns as a from as sexual selection.
With Walliserops has their trident combat to get the females attention. This does give the possibility for Walliserops as well some other trilobites to have sexual dimorphism like some modern day arthropods.
Further reading
A.D. Gishlick, & R.A. Fortey, Trilobite tridents demonstrate sexual combat at 400 Mya, Proc. Natl. Acad. Sci. U.S.A. 120 (4) e2119970120, https://doi.org/10.1073/pnas.2119970120 (2023).
