Context
A newly identified species of marine tardigrade, commonly known as a “water bear”, has been discovered off the Odisha coast and named Actinarctus odissi. The discovery is significant as it is the first new species reported from the genus Actinarctus in the last 43 years.
About Actinarctus Odissi
- It was discovered in the shallow coastal waters near Markandi along the Odisha coast.
- The name “odissi” has been given in honour of Odisha’s classical Odissi dance form.
- It possesses a dome-shaped body with transparent wing-like flaps known as alae.
- Unlike related tardigrades, it has shorter lateral wings, simple hind-leg sensory organs and blunt sensory appendages.
- Its back shows distinct sculpturing with tiny pillar-like structures.
Tardigrades
- Tardigrades are microscopic, segmented invertebrates also known as “water bears” or “moss piglets”.
- Around 1,300 tardigrade species have been identified globally.
- They are found in diverse habitats, especially freshwater and moist terrestrial environments.
- Marine tardigrades account for nearly 17% of known tardigrade species.
- They generally measure between 0.05 mm and 1.2 mm and possess four pairs of clawed legs.
- Tardigrades feed on fluids from plant cells, animal cells and bacteria.
- They are known for surviving extreme conditions such as intense heat, freezing temperatures, radiation and even outer space.
- Under unfavourable conditions, they enter a dormant “tun” state in which the body dehydrates and metabolic activity drops drastically, enabling survival for years or even decades.
