Anemonia majano (Majano Anemone) Reproduction & Pest Control Guide

How the pest majano anemone Anemonia majano spreads by asexual fission and pedal laceration plus pelagic spawning, why it overruns reef tanks, and how to control it.

Overview

Anemonia majano, the majano anemone, is a small true sea anemone of the family Actiniidae. It is a hitchhiker pest that enters reef tanks on live rock and frags and, like other nuisance anemones, can overrun a reef. It hosts zooxanthellae for photosynthetic nutrition. It is documented here for awareness; it should be controlled, not introduced intentionally.

Reproductive Mode

As a true sea anemone, Anemonia majano can reproduce both asexually and sexually. Wikipedia's general sea-anemone account confirms that both sexual and asexual reproduction occur in sea anemones, which underlies the rapid clonal spread typical of nuisance species.

Asexual Propagation

Sea anemones reproduce asexually by longitudinal fission, pulling themselves apart into genetically identical individuals; by the rarer transverse fission; and by pedal laceration, in which a ring of material breaks from the pedal disc and the fragments regenerate into new clones. Because any disturbed fragment can regenerate, careless removal tends to multiply the problem.

Sexual Reproduction

Sexual reproduction in sea anemones is broadcast and pelagic: males release sperm to stimulate egg release, fertilization occurs in the water column or internally, and the planula larva drifts before settling. This open-water phase is not relevant to home propagation; for a pest, it simply represents another spread route in the wild.

Common Challenges

Manual removal risks fragmentation and reseeding, so the column must be killed or fully extracted without leaving remnants. Quarantining and inspecting new rock and frags before adding them is the most reliable way to keep this anemone out of a display.