Dictionary > Turbellaria

Turbellaria

Definition
noun
A taxonomic class belonging to the phylum Platyhelminthes (flatworms) characterized by having a body covered externally with vibrating cilia
Supplement
The phylum Platyhelminthes (flatworms) is comprised of parasitic worms characterized mainly by their flattened, bilaterally symmetrical body. This phylum includes the four classes: (1) Turbellaria, (2) Trematoda, (3) Monogenea, and (4) Cestoda.
Turbellaria is comprised of flatworm species (turbellarians) that are not exclusively parasitic and possess a body covered externally with vibrating cilia. They have flat, ribbon-like, or leaf-like shapes. Other characteristics that turbellarians share with other Platyhelminthes are as follows: (1) bilateral symmetry, (2) reliance on diffusion for internal transport of metabolites due to the absence of specialized respiratory and circulatory systems, (3) being tripoblastic, (4) lacking in internal body cavity (thus, are acoelomates), and (4) undigested material being regurgitated through the mouth due to lack of anus.
There are about 4,500 turbellarians identified.1 The taxonomic class includes the Rhabdocoela and Dendrocoela. Formerly, the nemerteans were included in this group. Many of them are free-living. Others are parasitic.
Word origin: Latin turbellaria, Latin turbellae ‎(“bustle”), turba ‎(“confusion”)
Scientific classification:

  • Kingdom: Animalia
  • Phylum: Platyhelminthes
  • Class: Turbellaria Ehrenberg, 1831

Common name:

  • turbellarian

See also:

Reference(s):

1 Ruppert, E. E., Fox, R. S., & Barnes, R.D. (2004).Invertebrate Zoology (7 ed.). Brooks / Cole. pp. 226–269.


You will also like...

Pikas are an indicator species for climate change
Indicator Species and Endangered Species

Certain species are capable of expressing characteristics indicative of the state of the ecosystem they occupy. They are..

Kidneys
Kidneys and Regulation of Water and Inorganic Ions

The kidneys are responsible for the regulation of water and inorganic ions. Read this tutorial to learn about the differ..

Nephrolepis exaltata
Vascular Plants: Ferns and Relatives

Ferns and their relatives are vascular plants, meaning they have xylem and phloem tissues. Because of the presence of va..

Water Cycle
The Water Cycle

The water cycle (also referred to as the hydrological cycle) is a system of continuous transfer of water from the air, s..

Still Water Animals
Still Water Animals

Animals living in aquatic habitats have diversified and evolved through time. They eventually occupy ecological niches a..

mRNA
Protein Synthesis

Part of the genetic information is devoted to the synthesis of proteins. mRNA, a type of RNA, is produced as a transcri..