Cancer Maenas, commonly known as the European green crab, is a species of crab found along the coasts of Europe and North America. It is characterized by its greenish color, five spines on each side of its shell, and a broad, oval shape. This crab typically inhabits rocky shores, estuaries, and tidal pools. This species is known for its adaptability and aggressive behavior, which allows it to thrive in various environments. Cancer Maenas plays a significant role in its ecosystem, influencing the population dynamics of other marine organisms. However, it is also considered an invasive species in some regions, impacting local fisheries and habitats.