One of the Arabian Cowries (Mauritia arabica) in our Living Gallery recently laid egg capsules. We moved some of the egg capsules to our lab and, six days later, larval cowries emerged from the capsules!
Although some species of mollusks spend most of their early development inside egg capsules, many undergo a free-swimming larval phase before settling to the bottom as adults. These swimming "toddlers" are known as veliger larvae, a type of larva found only in mollusks. Most veliger larvae are capable of feeding by creating micro-water currents that bring food (mostly microalgae) to their mouths.
To that end, they beat small, hair-like cilia that are deployed along the edge of expansions called velar lobes (photo above). The short video clip below, shot by our Senior Aquarist Carly Hulse, shows the veliger larvae and the cilia in movement.