Chondracanthidae

Chondracanthidae is a family of parasitic copepods that are obligate ectoparasites of marine fish. These copepods are characterized by their highly modified and often sexually dimorphic bodies, with females typically being much larger and more robust than males. The females possess a specialized attachment organ that allows them to firmly adhere to their host's body, often embedding themselves within the skin or fins. Chondracanthids exhibit a wide range of host specificity, with some species infecting only a single host species, while others parasitize a broader array of fish.

The life cycle of chondracanthids involves several naupliar and copepodid larval stages that are free-swimming. These larvae search for a suitable host to attach to. Once attached, the copepodid molts into a chalimus larva, which then develops into an adult. Sexual dimorphism is prominent, with the small, mobile males often found attached to the female's body. These parasites can cause significant damage to their hosts, leading to epidermal lesions, inflammation, and in heavy infestations, can affect the fish's health and survival. They are found worldwide in marine environments, infesting various commercially important fish species. Research on chondracanthids is ongoing, focusing on their biology, host-parasite interactions, and their impact on fish populations.