Why is the phylum Porifera grouped in kingdom Parazoa?

Sponge (Porifera) embryos have no germ layers, and therefore no true tissue differentiation. This feature categorizes sponges as separate from other animals whose embryos have two or three germ layers that generate true tissue differentiation. read more

The parazoa group is now considered paraphyletic. It is not included in most modern cladistic analyses. When referenced, it is sometimes considered an equivalent to Porifera. read more

Video: Parazoa: Definition and Characteristics The sub-kingdom Parazoa is a special group of animals that are unlike any other. In this video lesson, you'll learn about the characteristics of Parazoans and identify what makes them a unique section of the Animal Kingdom. read more

The Parazoa, are a proposed clade of animals. Traditionally, Parazoa, literally translated as"beside the animals", only consisted of Porifera and the Placozoa. It still is a basal animal group, but has been refuted in the original sense (i.e. as sister of the Eumetazoa). read more