Spionidae
Grube 1850
Taxonomy
| Phylum | Annelida |
| Class | Polychaeta |
| Subclass | Palpata |
| Order | Canalipalpata |
| Suborder | Spionida |
| Family | Spionidae |
Size
- Variable.
Description
- Known as 'palp worms'.
- Selective deposit feeders.
Distinguishing characteristics
- Two prominent grooved palps to locate prey.
- Palps are generally grooved, ciliated and posses sensory structures.
- Nuchal organs form posterior projections.
- Specialised chaetae.
- Ciliary tufts and bands.
Distribution
- Widely distributed throughout the world.
- Larvae of Spionidae are generally the most common developmental stages of polychaetes found in plankton samples.
Ecology
- Benthic sessile or semi-sessile.
- Deposit or suspension feeders.
- Various types of development:
- pure broadcast spawning
- planktotrophic and/or lecithotrophic larvae (brooding in capsules or cocoons).
- Periods of development can be long lasting and can result in large numbers of larvae in coastal areas.
- Locomotion: Lecithotrophic larvae are weak swimmers. Planktotrophic larvae are strong swimmers (performed by propulsion by the cilia).