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How do pearlfishes use sea cucumbers and other invertebrates as hosts?
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paracanthopterygian
Oyster toadfish (Opsanus tau).
Pearlfishes, which belong to the order Ophidiiformes within the superorder Paracanthopterygii, are known for their unique symbiotic relationship with various marine invertebrates.12
These slim, eel-shaped fish utilize hosts such as sea cucumbers, pearl oysters, and starfishes for shelter. When interacting with a sea cucumber, the pearlfish enters the host's body through its anus. Once inside, some species of pearlfish have been observed feeding on the host's internal reproductive and respiratory organs.1