cyprid

The term "cyprid" refers to a specific larval stage in the life cycle of certain crustaceans, most notably barnacles. This stage is nonfeeding and characterized by strong swimming capabilities, following a profound metamorphosis from the nauplius larva.1

The cyprid larva's primary function is to find a suitable surface for settlement. This selection process is guided by various stimuli, including light, chemical cues, and tactile sensations. Once a suitable location is identified, the cyprid attaches itself permanently and undergoes a final metamorphosis into a juvenile barnacle, after which it cannot change its position.1

In some parasitic crustaceans, like certain rhizocephalans, the cyprid larva has a more complex role. It seeks out a specific host, attaches to it, and then metamorphoses, discarding most of its body parts while sending out rootlike structures to absorb nutrients from the host. The cyprid larva is a crucial developmental stage, bridging the gap between the free-swimming nauplius and the sessile adult form in many crustacean species.1