PPT Slide
http://www.zoo.utoronto.ca/zoo344s/2002Group9/EPITOKY.htm
An epitoke is the reproductive form that occurs in some polychaetes. It is produced by either transformation or budding. An atoke is the normal form of the polychaete (Highnam, 1977)
Some polychaetes have the ability to only transform part of their body (as in figure shown above.) or to form buds as an extension of their normal body.
In the above picture the left side of the worm (light colored part) is the epitoke, mature, part of the worm. The right side (dark part) is the atoke. This figure was adapted from Caspers, 1984.