Veliger

Definition

A veliger is the larval stage of certain molluscs, including bivalves and gastropods. It follows the trochophore stage and precedes the adult form, possessing ciliated lobes for swimming and feeding.

5 Must Know Facts For Your Next Test

1. Veligers are characteristic of many marine molluscs and play a crucial role in their life cycle.
2. The veliger stage typically includes structures like a velum, shell, and foot that are essential for movement and feeding.
3. During the veliger stage, larvae undergo torsion, particularly in gastropods, which repositions their body parts.
4. The transition from trochophore to veliger involves significant morphological changes tailored for planktonic life.
5. Veligers eventually settle onto a substrate where they metamorphose into juvenile molluscs.

Review Questions

• What key structures are found in a veliger that aid in its swimming and feeding?
• At what point in the mollusc life cycle does the veliger stage occur?
• How does torsion during the veliger stage affect gastropod development?

Related terms

Trochophore: The earlier larval stage of some molluscs characterized by a simple, ciliated body used for swimming.

Torsion: A developmental process in gastropods involving the twisting of the body that repositions internal organs.

Planktonic: Referring to organisms that drift or float in the water column and are unable to swim against currents.