tertiinid

Tertiinid is a minor group of euharpacticoid copepods, a type of small crustacean. They are primarily deep-sea dwellers, inhabiting the ocean's abyssal and bathyal zones. Tertiinid copepods are characterized by their small size and distinctive body structure, featuring a long, slender body shape, often with a segmented exoskeleton.

These copepods are filter feeders, using their antennae-like appendages to capture small particles and organisms from the surrounding water. They are found in various parts of the world's oceans, often in areas with low oxygen levels and high pressures, where few other organisms can survive.

Some species within this group are notable for their role in serving as food sources for larger deep-sea predators. However, detailed studies on the specific feeding habits and ecological significance of tertiinid copepods are limited due to their relatively obscure nature.

Tertiinid distribution appears to be widespread, but specific records of such copepods are predominantly found in oceanic regions, particularly in areas off the coast of Europe, Africa, and North America. The taxonomy of the tertiinid group remains under development, with some authorities recognizing the tertiinids as a distinct subfamily within the euharpacticoid family, while others view them as a separate family.

Limited freshwater tertiinid species have been documented, yet these are rarely encountered in aquatic environments outside of marine ecosystems. Overall, tertiinid copepods operate in regions of great pressure and low visibility, displaying a significant level of basic and specific structural adaptation to their specialized habitat.