5 Turbellaria Characteristics & Types: Facts You Should Know!

Turbellaria is commonly known as Planaria and is a member of Phylum-Platyhelminthes in Animal Kingdom. Let us see various types and characteristics of turbellaria.

Turbellaria are free-living flatworms. They have the power of regeneration. They do not have a coelom, anus or another specialised organ system for vital functions. That is why they eject undigested food materials through their mouth.

Let us see different types of turbellaria with their characteristics, lifespan over this planet, life cycle, and other interesting facts in this article.

Turbellaria types

  • Temnocephala lamothei
  • Dugesia aenigma
  • Dugesia bifida
  • Planaria simplex
  • Girardia dorotocephala
  • Girardia tigrina

Temnocephala lamothei

Temnocephala lamothei are mainly aquatic invertebrates and are mostly free-living. They do not possess cuticles as the outer membrane and have syncytial (multinucleate) skin and are covered with microvilli. The body is flat and ribbon-like and is mostly black and grey in colour. They are extremely sensitive to light as they are nocturnal.

Dugesia aenigma

Dugesia aenigma lacks some vitals like respiratory, and well-developed circulatory organs as they perform these functions through their general body surface. They have an excretory organ and a balancing organ like statocysts. Ocelli are present for better vision.

Dugesia bifida

Dugesia bifida lacks a digestive system incompletely but some digestive enzymes are found inside the gut. They are hermaphroditic and are capable of both types of reproduction. Laying eggs are sometimes attached to rocks or any hard surface initially or sometimes encapsulated into cocoons.

Planaria simplex

Planaria simplex are the true flatworms with a “flat body surface“. Approx 3000+ species are found from this genus. They are involved in benthic ecosystems and are an important link between small organisms like plankton and large fishes within aquatic food webs.

Girardia dorotocephala

Girardia dorotocephala are mainly native to North America followed by Mexico and Japan. They show cannibalism for food consumption and the uptake of nutrients. These organism splits into two or many pieces to give birth to an individual. They also reproduce by budding

Girardia tigrina

Girardia tigrina organism is initially found in Europe and later on in nearby places in Germany. They are carnivores as they feed upon some polychaetes and other smaller invertebrates. Sometimes they also use their ability of regeneration as a mode of reproduction.

799px Girardia sp
Image credits: Girardia tigrina by Eduard Solà
(CC BY-SA 3.0) from Wikimedia commons

Turbellaria lifespan

The total number of years survived by an organism is known as the average lifespan. Let us see how long the planarians live over the planet.

The lifespan of turbellarians is approx. 70-140 days. It is the time interval between the birth and death of these organisms. But due to climatic changes, the expected value of lifespan is decreasing day by day.

Turbellaria life cycle

A lifecycle is defined as the series of stages an organism goes through throughout its life span. Let us see how many life stages are covered by the turbellarians.

  • Turbellaria grew as larvae initially then during juvenile, they became an individual adult.
  • Turbellaria are hermaphrodites, that is, both male and female genital organs are present in the same organism and can inseminate easily to produce offspring.
  • Different stages of the life cycle start from birth and end upon the death of that organism.
  • Beyond wound healing, the ability of tissue regeneration also helps in cloning the organisms.
  • Splitting pieces will become exactly similar to their parents and develops into an adult.

Conclusion

In my conclusion, turbellaria is also known as planaria. Relatively, the life cycle of free-living organisms is simple concerning parasitic planarians. Laid eggs are encased inside the cocoon, after embryonic development, they got matured in water and lived their life as an individual.

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