Definition
The family Carapidae encompasses a group of slender, often translucent fishes, recognized by their unique habit of residing within other marine creatures. They're like the ultimate hide-and-seek champions of the sea, opting to live inside invertebrates like sea cucumbers, starfish, and even oysters. Some are parasitic, acting like tiny vampires, while others are commensal, simply enjoying the free rent. This group displays an impressive variety of lifestyles, from freeloaders to outright thieves! Their elongated bodies are perfectly designed for navigating the internal spaces of their hosts. Carapidae presents a fascinating case study in evolutionary adaptation.