March 1, 2010

Chiton, Langkawi

Chiton from P. Langgun
Langkawi, Kedah

Chitons are small to large, primitive marine molluscs in the class Polyplacophora. There are 900 to 1,000 extant species of chitons in the class, which was formerly known as Amphineura.

These mollusks are also sometimes commonly known as sea cradles or "coat-of-mail shells". They are also sometimes referred to more formally as loricates, polyplacophorans, and rarely as polyplacophores.

Chitons have a shell which is composed of eight separate shell plates or valves. These plates overlap somewhat at the front and back edges, and yet the plates articulate well with one another. Because of this, although the plates provide good protection for impacts from above, they nonetheless permit the chiton to flex upward when needed for locomotion over uneven surfaces, and also the animal can slowly curl up into a ball when it is dislodged from the underlying surface. The shell plates are surrounded by a structure known as a girdle. Source- Wikipedia

1 comment:

tushe san said...