Reproductive biology of two epizoic anemones from the deep north-eastern Atlantic Ocean

Abstract

The reproductive biology of two epizoic deep-sea anemones reveals contrasting reproductive strategies. Amphianthus inornata (Cnidaria: Anthozoa) lives attached to the bathyal gorgonian Acanella arbuscula (Cnidaria: Anthozoa). Females of A. inornata increase in wet body weight as a result of increased oocyte production until 40% of the body weight is reproductive tissue. The anemone reproduces on a seasonal basis, releasing eggs in the early spring of each year. By contrast, Kadosactis commensalis (Cnidaria: Anthozoa) lives attached to the body wall of the abyssal holothurian Paroriza prouhoi (Echinodermata: Holothurioidea). This anemone is a protandric hermaphrodite, females being found only at the anterior end of the holothurian, whilst males are found at any point on the host. Females have a significantly higher wet weight than males and neither sex shows any reproductive seasonality.