Yes, single-celled producers known as extremophiles can be found in many aquatic environments and are capable of surviving in extreme temperatures. These extremophiles can be found in various extreme habitats such as hot springs, hydrothermal vents, deep-sea trenches, and even polar environments. Some examples of extremophiles that can survive in extreme temperatures include thermophilic archaea and bacteria that can thrive in hot springs with temperatures exceeding 70°C (158°F) and psychrophilic microorganisms that can survive in sub-zero temperatures in the Antarctic.
