Flatworms
| |
| Kingdom: | Animalia |
|---|---|
| Subkingdom: | Eumetazoa |
| Clade: | ParaHoxozoa |
| Clade: | Bilateria |
| Clade: | Nephrozoa |
| Unranked: | Protostomia |
| Unranked: | Spiralia |
| Clade: | Rouphozoa |
| Phylum: | Platyhelminthes |
| Source: Integrated Taxonomic Information System | |
Flatworms are the simplest of the worm groups. There are roughly 20,000 species. Flatworms are found globally and can be free-living or parasitic. One of the best-known flatworms is the tapeworm.
Habitat
Diet
Reproduction
Anthropogenic Benefits
Anthropogenic Drawbacks
| Attribute | Cnidarians and Ctenophores | Platyhelminthes (flatworms) | More "advanced" bilaterians }} |
|---|---|---|---|
| Bilateral symmetry | No | Yes | |
| Number of main cell layers | Two, with jelly-like layer between them (mesoglea) | Three | |
| Distinct brain | No | Yes | |
| Specialized digestive system | No | Yes | |
| Specialized excretory system | No | Yes | |
| Body cavity containing internal organs | No | Yes | |
| Specialized circulatory and respiratory organs | No | Yes | |