Polychaetes of this genus thrive in nutrient-rich environments and can often be found in polluted marine areas that are often sites of human activity.

Found in the oceans surrounding Europe, Asia, the Mediterranean, and beyond, they can survive in low-oxygen environments and are known to be sulfide tolerant, allowing this genus to live in areas most species cannot.

[3] Ophryotrocha is often used as a scientific test species due to their high fecundity, stress tolerance, and myriad of sexual systems found within the genus.

[4] All polychaetes of this genus are laid in batches of roughly 100 eggs and the majority of species start out in a free-moving larval stage as protandrous hermaphrodites.

[5] In simultaneous hermaphrodites, each adult has a pair of gonads that produce gametes which are emitted into the water column where external fertilization occurs.