What is the function of a archaeocyte? what group does it belong to?

Porifera - totipotent cells that can change into all of the other types of sponge cells, with a large nucleus and undifferentiated shape also do: 1. Food digestion (after lysis) 2. Storage of nutrients 3. Differentiate into gametes 4. Secrete skeletal elements • calcareous spicules • siliceous spicules • spongin