The eggs are typically small, about 0.0035 in (90 ^m) in diameter, and contain sufficient yolk reserves to support the developing limpet through settling and metamorphosis. Larger species produce millions of eggs per reproductive season and typically have yearly cycles. Smaller species produce far fewer eggs, but can be gravid and capable of spawning gametes year-round. Patellogastropod larvae pass through a trophophore stage and a veliger stage before settling and undergoing metamorphosis. Parental brood protection has evolved at least twice in the patellogastropods. In some species, the eggs are retained in the mantle cavity over the head, where they are fertilized, and develop into crawl-away young. Other taxa have internal brood chambers and copulatory structures. In some Antarctic species, spawning occurs when individuals stack one on top of another, thereby reducing the distance between individuals and increasing the probability of fertilization.
Was this article helpful?