Page 297 - (DK) Ocean - The Definitive Visual Guide

ARTHROPODS 295

SUBPHYLUM CRUSTACEA SUBPHYLUM CRUSTACEA The brightly colored peacock mantis Such power is created by a special,
shrimp is a stomatopod crustacean. saddlelike hinge-joint in these legs,
Giant Mussel Shrimp Peacock Like all members of this group, it is a which acts like a spring. The peacock
voracious predator. Its large, mobile, mantis shrimp can smash the shells of
Mantis Shrimp
Gigantocypris muelleri compound eyes have sophisticated gastropods and crabs and tackles prey
LENGTH stereoscopic and color vision that larger than itself. It excavates U-shaped
3
1 / 2– / 4 in (1.4–1.8 cm) Odontodactylus scyallarus includes some ultraviolet shades. It burrows or lives in crevices in rocks
LENGTH
HABITAT Up to 6 in (15 cm) uses sight when hunting, waiting or coral. After
Planktonic, intermediate quietly, like the praying mantis, for its hatching, its larvae
to deep sea HABITAT unsuspecting prey to come within enter the plankton,
Warm water near reefs
with sandy, gravelly, or reach, then striking using its powerful, where they develop
shelly bottoms over a few weeks
DISTRIBUTION Atlantic, Southern Ocean, western clublike second pair of legs with
Indian Ocean immense speed—about 75 mph before drifting down
DISTRIBUTION Indian and Pacific oceans (120 km/h)—and force (up toward the sea floor to
Like all ostracod crustaceans, the giant 100 times its own weight). make their own homes.
mussel shrimp has a carapace that
encloses its body, so that its seven pairs
of limbs are almost hidden from view.
Its large, mirror eyes with parabolic-
shaped reflectors focus light on to a flat
plate in its center. It is planktonic, but
lives at greater depth than many forms
of plankton, usually below 650 ft
(200 m), where it feeds on falling
detritus. The picture shows a large
female carrying embryos, which are
clearly visible through the carapace.

not markedly separated from its body, Ocean, where they form a vital link in
SUBPHYLUM CRUSTACEA SUBPHYLUM CRUSTACEA
which is flattened, about twice as long the food chain, being eaten in vast
Sea Slater as it is broad, and ends in two forked Antarctic Krill quantities by baleen whales, seals, and
projections called uropods. various fish. Krill rise to the surface at
Ligia oceanica As adults, sea slaters have six pairs Euphausia superba night to feed on phytoplankton, algae,
LENGTH of walking legs until their final molt, LENGTH and diatoms. For safety they sink to
Up to 1 1 / 4 in (3 cm) after which they have seven. The sea Up to 2 in (5 cm) greater depths during the day. The
HABITAT slater is not generally seen during HABITAT feathery appearance of this species is
Coasts with rocky the day unless it is disturbed, and it Planktonic due to its gills, which, unusually, are
substrata emerges from its hiding place only at carried outside the carapace. Their
night to feed on detritus and decaying filamentous structure increases the
DISTRIBUTION Atlantic coasts of northwestern seaweed. Sea slaters mature at about DISTRIBUTION Southern Ocean surface area available for gaseous
Europe two years of age and usually breed exchange. Antarctic krill also have
only once before dying. All oceans contain krill—small, large light organs, called photophores.
Commonly found under stones and shrimplike, planktonic crustaceans The light is thought to help them
in rock crevices, the sea slater is a uropod that live in open waters. Antarctic group together. They spawn in spring,
seashore-dwelling a member of krill live in vast numbers in the during which females may release
the isopods (a group that also subantarctic waters of the Southern several broods of up to 8,000 eggs.
includes woodlice). It lives in
the splash zone, but can survive
periods of immersion in salt
water. Its head, which has a pair
of well-developed compound
eyes and very long antennae, is antenna

SUBPHYLUM CRUSTACEA Amphipod crustaceans, such as the
sand hopper, live in large numbers
Sand Hopper in the splash zone of any shore where
there is rotting seaweed. Their life
Orchestia gammarellus cycle takes about 12 months and the
LENGTH female usually produces only one clutch
3
1 / 16 – / 8 in (2–10 mm) of eggs, which she keeps in a brood
HABITAT pouch, where they hatch after one
Splash zone of sandy to three weeks. The young leave the
shores pouch about a week later when their OCEAN LIFE
mother molts. Sand hoppers are also
DISTRIBUTION Atlantic coasts of northeastern Canada known as sand fleas because they
and northwestern Europe jump about in a similar way and have
similar laterally compressed bodies.