High Quality Content by WIKIPEDIA articles! Vetulicolia is an extinct phylum encompassing several Cambrian organisms. Their bodies comprise two parts; their front is voluminous and is tipped with a large "mouth" and a row of five round to oval-shaped features on each side which have been interpreted as gills - or at least openings in the vicinity of the pharynx. Their posterior section comprises seven segments. They lack preserved appendages of any kind. The area where the anterior and posterior parts join is constricted. Their affinity is very uncertain; they have been considered to represent stem- and crown-group arthropods, stem-group vertebrates, and early deuterostomes.