VCSU Macro-Invertabrate Lab

Phylum Platyhelminthes - The Flatworms

The only members of Platyhelminthes we find in fresh water are in the class Turbellaria, the flatworms. Surprisingly, flatworms are not always flat. They may be cylindrical. They usually have a region at their anterior end that resembles a head with eyespots. The body is covered with cilia. Flatworms are usually found near the bottom of the water body where they eat plant or animal tissue, either living or dead.

General Life cycle - Flatworms can reproduce asexually or sexually. Asexually they may simply divide in halves and each half will regenerate the missing parts. Or they may break into many parts and each part will become a new individual. Otherwise flatworms in the US are hermaphrodites. After mating with a partner an egg is produced and laid in a cocoon. Young look like small adults after emerging and slowly develop until sexual maturity.

Identification - Flatworms are either flat or cylindrical. They display bilateral symmetry, which means the right side looks much like the left side of the body. A single opening to the digestive tract serves as both mouth and anus. The body is soft and tapered at both ends.

Warning: include(../ssi/tempbase.php): failed to open stream: No such file or directory in /var/www/ on line 58

Warning: include(): Failed opening '../ssi/tempbase.php' for inclusion (include_path='.:/usr/local/phplib:/usr/local/templates/v7/common/ssi:/usr/share/php') in /var/www/ on line 58