Knobby starfish are so called because they have a lot of knoblike
projections which start out fairly light colored and tend to darken and beome more numerous as they get older.
Knobby starfish are often used in crafts when an unuusal starfish is desired to give that unique look. They are also good for
educational classrom use to illustrate the diversity of echinoderms in
general and starfish in particular.
The knobbystar goes against what people expect when they think of a starfish. Though it does have 5 legs (arms?) it's odd
appearance surprises a lot of people.
Young children who tend to be "tactile" love their bumpiness. Though they are more fragile than
junglestars they are common and
inexpensive enough to be easily replaced. They are also good as
giveaways or prizes for children to take home.