😈🪲 This small isopod of the intertidal zone is 6 to 7mm long, and also called horned isopod. You can easily guess why!

🦷🦷 The name ‘bidentata’ (latin for ‘two-toothed’) comes from the two tooth-like projections on its back, which are unique to males of this species. It makes the pleotelson a key feature for the identification of the sex and the species. In 𝘋𝘺𝘯𝘢𝘮𝘦𝘯𝘦 𝘣𝘪𝘥𝘦𝘯𝘥𝘢𝘵𝘢 males, the 6th segment is longer and have this typical pointy shape.

⚧️⚧️ This is a great exemple of 𝘀𝗲𝘅𝘂𝗮𝗹 𝗱𝗶𝗺𝗼𝗿𝗽𝗵𝗶𝘀𝗺, that refers to differences in appearance, size, or other characteristics between males and females of the same species. Sexual dimorphism can be observed in many animal species, including mammals, birds, reptiles, fish, and insects.

🏊‍♂️🦶Uropods are paired appendages found at the rear end (posterior) of crustaceans, such as lobsters, crabs, shrimp, and isopods. Their structure and function can vary widely but they are typically used for locomotion and swimming.

🦐🌋The anatomy of the barnacle – as adults, represent a unique example of modified crustaceans, resembling a sessile “shrimp” affixed to rocky substrates. Their calcareous shell plates serves as both protection and anchorage.

💧🚪Sessile (fixed) animals in the intertidal zone have evolved strategies to combat desiccation between high tides, like these opercular plates that help them retain moisture. It’s all about survival skills!

➿🦶Ever wondered where the name 𝘊𝘪𝘳𝘳𝘪𝘱𝘦𝘥𝘪𝘢 comes from? It’s derived from the Latin words 𝘤𝘪𝘳𝘳𝘪𝘵𝘶𝘴 “curly” and 𝘱𝘦𝘥𝘪𝘴 from 𝘱𝘦𝘴 “foot”. Together, it means “curly-footed”, as a reference to the barnacle’s distinctive curled legs used in filter-feeding.

📚🙇 Charles Darwin wasn’t just about finches and evolution. He spent eight years studying barnacles (1846-1854), laying the groundwork for Cirripedia studies, and eventually influencing his groundbreaking theories of natural selection. Even the father of evolution had a barnacle phase!