They reproduce by laying oval-shaped eggs, about 1 mm in length.

[2] Pearlfishes are unusual in that the adults of most species live inside various types of invertebrates.

However, some species are known to be parasitic towards sea cucumbers, eating their gonads and other internal organs.

Pearlfish larvae can be distinguished by the presence of a long filament in front of their dorsal fins, sometimes with various appendages attached.

[2] The genera are divided into three major groupings based on their level of symbiosis: