Phyllodocida
Phyllodocida is an order of marine polychaetes, commonly known as “leaf worms” or “paddle worms.” These segmented worms are found in a variety of marine environments worldwide, from shallow coastal waters to the deep sea. They are characterized by their flattened bodies, often with paddle-like parapodia (lateral appendages) that aid in swimming and burrowing. Phyllodocida includes a diverse group of species, ranging in size from a few millimeters to over a meter in length.
Characteristics
Phyllodocida species share several distinct characteristics:
- Flattened Body: Their bodies are typically flattened dorsoventrally, giving them a ribbon-like appearance. This shape helps them maneuver through their environment, particularly in sediments or among seaweed.
- Paddle-like Parapodia: They possess distinctive paddle-like parapodia that are often larger and more prominent than those found in other polychaete orders. These parapodia assist in swimming, burrowing, and crawling.
- Prostomium: Their prostomium (head) is usually simple, often bearing a pair of antennae and one or two pairs of eyes. Some species have additional sensory structures like palps.
- Diversity in Feeding Habits: While many Phyllodocida species are carnivorous, feeding on small invertebrates, others are detritivores, feeding on decaying organic matter. Some species are even known to be omnivores.
Environments
Phyllodocida species are found in a wide range of marine environments, including:
- Intertidal Zones: Many species thrive in the intertidal zone, where they can be found burrowing in sediments or among seaweed.
- Subtidal Zones: They are also common in subtidal zones, where they live on the seabed or among seagrass meadows.
- Deep Sea: Some Phyllodocida species inhabit the deep sea, where they have adapted to the challenging conditions of low light and high pressure.
References
For more detailed information, consult the following resources: