Sacabambaspis is a jawless, prehistoric fish from the Ordovician period that swam into modern pop culture in 2023. The meme exploded after a photo of an anatomically questionable reconstruction model at the Helsinki University Museum of Natural History went viral on Japanese Twitter (X). Users were instantly captivated by its stunned expression, featuring forward-facing eyes and a permanently open, O-shaped mouth. It has since become the ultimate symbol for a state of total bewilderment or a 'no thoughts, head empty' mindset, inspiring massive amounts of fan art, 3D animations, and niche history memes across the globe.