The Chocolate Chip Sea Star (Protoreaster nodosus) is a marine (saltwater) starfish in the Oreasteridae family. It is also known as the Horned Sea Star. It is an invertebrate, because it does not have a backbone.It is not a fish, so scientists prefer to say that it is a sea star.

The Chocolate Chip Sea Star has five elongated tube limbs, called arms or feet. It has several black or dark-brown tubercles on its arms. It has a greyish body with dark stripes that connect the tubercles. 

It grows to about 30 centimetres (12 inches) in length. 

The Chocolate Chip Sea Star is native to the Indian Ocean and the Pacific Ocean, in the Indo-Pacific region. It prefers shallow pools and lagoons in tropical coral reefs.

It eats soft corals, sponges, tubeworms, clams, and other starfish. Its mouth is in the centre of the arms on the lower surface. It is a detritivore, which means that it also eats detritus found on sponges and algae. Detritus is the decomposing or dead parts of an animal.

It can regenerate its arms if they become damaged or broken. It can also lose an arm on purpose to confuse a predator. The arm will grow back. This is called autotomy. 

Its predators include pufferfish, triton shells, shrimp, and sea anemones.

It is diurnal, active during the day. 

The Chocolate Chip Sea Starcan breed both sexually and asexually. It is diocious, which means that each individual is either male or female. The female releases eggs into the sea. She has about 2.5 million eggs, and most of them are eaten by fish. 

The eggs hatch into larvae, which float in the sea for about 87 days before settling on the sand on the ocean floor. The larvae then undergo metamorphosis and change into young sea stars. 

The Chocolate Chip Sea Star lives for 7-8 years. 

Location of photographs: Aquarium de Paris-Cinéaqua, France

Photographer: Martina Nicolls

Martina Nicolls:SIMILAR BUT DIFFERENT IN THE ANIMAL KINGDOM