Polyandry is a polygamous mating system where a female has multiple male partners during the breeding season. This is a relatively uncommon form of polygamy and has only been reported in anemonefish (Amphiprioninae) and could be the case for deep sea anglerfish (Ceratiidae). Though anemonefish are generally monogamous, polyandry has been reported in some circumstances. In Deep Sea Anglerfish, multiple males can be attached to a large female, almost in a parasitic relationship where their circulatory system merges with the female’s. See polygamous; polygyny. (fishionary.fisheries.org/polyandry/)

Deep Sea Anglerfish have parasitic males that
could be considered polyandrous