Researchers have identified a new species, Megachelicerax cousteaui, from a 500-million-year-old fossil found in Utah's West Desert, which is now recognized as the earliest known chelicerate. This discovery extends the history of chelicerates, which include spiders and horseshoe crabs, by 20 million years. The fossil showcases a claw, the first clear evidence of a chelicera from the Cambrian period, indicating that important anatomical features of modern chelicerates were already developing during this time. The study, published in *Nature*, emphasizes the complexity of early arthropods and their evolutionary significance. The fossil was painstakingly uncovered over 50 hours of work, revealing intricate structures that suggest a transitional form between earlier arthropods and later species. Named after the famed marine explorer Jacques Cousteau, this finding underscores the importance of museum collections in advancing scientific knowledge and highlights how chelicerates have influenced ecosystems and human life throughout history.