  "Avoid incorporating modern elements or features that are not consistent with the prehistoric nature of the cephalopod. Ensure that the image stays true to the characteristics of the Cambrian-Ordovician period and the Plectronoceratoidea family. Steer clear of unrealistic colors or patterns that are not commonly found in marine environments. Avoid any visual cues that might detract from the desired photo-realistic appearance of the cephalopod, such as overly vibrant or synthetic-looking colors. Maintain a focus on accuracy and authenticity to create a visually compelling representation of a prehistoric cephalopod."