HERMIT CRABS are decapod crustaceans of the superfamily ———–PAGUROIDEA.  Most of the 1100 species possess an asymmetrical abdomen which is concealed in an empty GASTROPOD SHELL, carried around by the hermit crab, into which its whole body can retract..  Most frequently, hermit crabs use the shells of sea snails.
The tip of the hermit crab’s abdomen is adapted to clasp strongly on to the COLUMELLA of the snail shell.  As the crab grows, in size, it must find a larger shell and abandon the previous one.  This habit of living in a SECOND-HAND SHELL, gives rise to the popular name HERMIT CRAB, by analogy to a hermit who lives alone.  Many hermit crabs use VACANCY CHAINS (very interesting) to find new shells.  When a new, bigger shell becomes available, hermit crabs gather round it and form a kind of QUEUE —— from largest to smallest.  When the largest crab moves…

View original post 493 mots de plus