Enteropneusta, commonly known as acorn worms, are marine invertebrates belonging to the phylum Hemichordata. They are characterized by their elongated, soft bodies and a distinct three-part body structure, which includes a proboscis, collar, and trunk. Acorn worms primarily inhabit shallow coastal waters and burrow into the sediment. These organisms play a vital role in the marine ecosystem by recycling nutrients and aerating the seabed. Enteropneusta feed on organic matter and detritus, using their proboscis to capture food particles. Their unique features and ecological importance make them a subject of interest in evolutionary biology and marine studies.