The crustaceans are one of the truly dominant groups living on
coral reefs. However, due to the tiny size and cryptic habits of
many species, it is easy to under-estimate their impact on the reefs
The group is incredibly diverse with regards to size, shapes,
colors and life style. Not only does it include well known representatives
such as lobsters, shrimps and crabs, but also a wealth of microscopic
organisms that form a large portion of the zooplankton.
are typified by the presence of a calcium carbonate-based external
skeleton. Because of continuous growth throughout the life cycle,
the animal periodically outgrows its armor coating. Therefore the
shell is shed and replaced at regular intervals. When the shell
is shed and the new coat is still relatively soft the animal is
vulnerable to predators and therefore seeks shelter in a burrow
or other hiding place.
Generally the best time to observe crustaceans
is at night when many species emerge from their retreats to feed.
The most conspicuous crustaceans during daylight hours are those
that clean parasites from fishes. The so called cleaner shrimps
are frequently bright colored and occupy permanent stations that
are regularly visited by a variety of fishes.
species with a max. length of 25 cm. Its soft abdomen is put
into an empty snail shell for protection.
with a tiny red and white shrimp as commensally inside the
shell. Often seen at the Similan Islands.
shrimps are elongated crustaceans with a long, flattened tail.
The Peacock Mantis Shrimp is a very colorful species, feeding
on other shrimps, worms and small fishes.
is a pair of praying mantis-like claws, which are inflated
in the terminal segment, an adaptation to crush prey with
a strong smash.
species lives deep in crevices and holes, usually in large
numbers. They are distinct by large, bulging eyes and a humpback.
It is called dancing shrimp because of its unusual way of
moving on the ground, which resembles a tango dancer.
common cleaner shrimp with spiny, bristly body and legs. The
base of the legs are blue.
The species is always found in
pairs. Males are much smaller than the females.