1. scolidon or dog fish belongs to phylum Chordata nd Asterias or star fish belongs to phylum Echinodermata
2. Scolidon is very fast swimming cartilaginous fish, nd Asterias is a nocturnal slow creeping cranivorous marine animal.
3. star fish hav tube feet & scolidon doesn't hav any tube feet.
4. scolidon hav spindle shaped elongated body & star fish hav flat and star shaped body.
5. Scolidon feeds on crabs nd fishes ( carnivorous) & asterias feeds on molluscs nd worms.