Planaria is a genus of Tricladida in the family Planariidae.
Due to its excellent ability to regenerate, species of Planaria has also been used as model organisms in regeneration studies.
Description
Currently the genus
Planaria is defined as freshwater
Tricladida with oviducts that unite to form a common oviduct without embracing the bursa copulatrix and with an adenodactyl present in the male atrium. The testes occur along the whole body.
Planaria originally have habitats in dark, murky water which results in such sensitivity (Paskin et al., 2014). They are also sensitive to other stimuli such as chemical gradients, vibration, magnetic and electric fields (Deochand et al., 2018). Their central nervous system includes the anterior (head, brain and eyes) and middle (abdominal trunk and pharynx) (Deochand et al., 2018).
Diet
The food of
Planaria species includes freshwater
,
tubificid worms, and freshwater
, such as
of the genus
Asellus and
chironomid larvae.
In the United Kingdom,
P. torva is a successful predator of the invasive New Zealand mud snail (
Potamopyrgus jenkinsi).
Species
The following species are recognised in the genus
Planaria:
Application of planaria in research
These invertebrates are valuable models in toxicology, neuroscience, and pharmacology, offering ethical and cost-effective alternatives to vertebrate testing. Planaria’s simple nervous system, high sensitivity to environmental changes, and well-characterized genome make them particularly useful for studying chemical toxicity, wound healing, and neuroregeneration. Their ease of maintenance in laboratory settings further enhances their appeal for research. In pharmacology and neuroscience, planaria provide a unique opportunity to study the effects of psychoactive compounds, including investigations into drug addiction and withdrawal responses.
In drug delivery studies, they can be used to assess the biocompatibility and potential irritancy of pharmaceutical formulations, providing insight into their effects on biological tissues.
Additionally, their remarkable ability to regenerate lost body parts makes them an important model for stem cell research, offering insights into cellular and molecular mechanisms of regeneration.
