Thalassematidae

Thalassematidae is a family of marine peanut worms, a group of unsegmented worms with a proboscis and a burrowing lifestyle. They are classified within the phylum Sipuncula, also known as peanut worms. Thalassematidae comprises several genera, each with its own distinct characteristics and ecological roles.

Common Names

Members of the Thalassematidae family are commonly referred to as peanut worms, due to their characteristic peanut-shaped body when retracted. This family is not known to have any specific common names beyond "peanut worms."

Characteristics

Thalassematidae members share several characteristic features that distinguish them from other sipunculans:

  • Body Shape: They have a long, cylindrical body that can be retracted into a compact, peanut-shaped form.
  • Proboscis: A prominent, retractable proboscis extends from the anterior end of the body. It is used for feeding and burrowing.
  • No Segmentation: Unlike other segmented worms, Thalassematidae lack any external or internal segmentation.
  • U-shaped Gut: The digestive tract is U-shaped, with the anus opening near the mouth.
  • Respiration: Respiration occurs through the skin and the proboscis.

Environment

Thalassematidae species are found in a wide variety of marine environments, including:

  • Intertidal Zones: These worms are commonly found in the intertidal zone, where they burrow in sand or mud.
  • Subtidal Zones: They can also inhabit subtidal zones, extending to depths of several hundred meters.
  • Tropical and Temperate Waters: Thalassematidae are found in both tropical and temperate waters, with species distributed globally.

References

For further information on Thalassematidae, refer to these reliable sources: