Vetulicolia are primitive deuterostomes from the very early Cambrian of China. The have a body with gills (or at least slits in the vicinity of the pharynx) and a segmented tail. The Vetulicolia are believed to be very similar to the ancestors of all deuterostomes.
... town the population is spread out with 29.5% under the age of 18, 6.7% from 18 to 24, 33.6% from 25 to 44, 20.6% from 45 to 64, and 9.6% who are 65 years of age or older. ...