1. SIPUNCULA

2. Peanut worm

3. Peanut worms or sipunculids have a well developed coelom (BODY CAVITY)
Peanut worms or sipunculids have a well developed coelom (BODY CAVITY). They burrow efficiently. They use a proboscis or "introvert" with small tentacles to perform direct deposit feeding.

4. Hence the name…..

5. About 300 species
Not usually larger than 10 cm
The most unusual thing is their mouth covered with 18-24tentacles
No segmentation
(remember)Mollusks have segmentation

6. Not very well studied
They are not classified with mollusks because of the lack of mantle and visceral mass
Not classified with annelids because of the lack of segmentation and bristles

7. They are burrowers and deposit feeders (detritus)
Not very well studied (I wonder why?)