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Animal Taxonomy
Kingdom: Animalia
Systematic Position
Kingdom: Animalia
Subkingdom: Eumetazoa
Division: Triploblastica
Sbdivision: coelomates
Phylum: Mollusca
1-Class: Gastropoda
Example: snails
Phylum: Mollusca
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Mollusca includes snails and slugs, octopuses and squids.
Most mollusks are marine, though some inhabit fresh water, and
some snails and slugs live on land.
Mollusks are soft-bodied animals, but most are protected by a
hard shell of calcium carbonate.
All mollusks have a muscular foot for locomotion, a visceral mass
with most of the internal organs, and a mantle.
Most mollusks have separate sexes, with gonads located in the
visceral mass, and some are hermaphrodites.
1-Class: Gastropoda
Example: snails
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Most Gastropoda are marine, but there are also many
freshwater species.
The anus and mantle
cavity are above
the head in adults.
• Most gastropods are protected
by a spiraled shell.
• Other species have lost
their shells entirely and
may have chemical
defenses against predators.
• Many gastropods have distinct
heads with eyes at the tips of
tentacles.
• They move by their foot.
• Some species are predators.
Kingdom: Animalia
Systematic Position
Kingdom: Animalia
Subkingdom: Eumetazoa
Division: Triploblastica
Sbdivision: coelomates
Phylum: Mollusca
2- Class: Cephalopoda
Example: Octopus
2- Class: Cephalopoda
Example: Octopus
• Cephalopods use rapid movements toward their prey which they capture with
several long tentacles.
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A mantle covers the visceral mass, but the shell is reduced and internal in squids
missing in many octopuses.
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The foot of a cephalopod
(“head foot”) has been
modified into the
muscular siphon and
parts of the tentacles
Most octopuses live on
the seafloor.
Cephalopods have an
active, predaceous
lifestyle.
They have a welldeveloped nervous
system with a complex
brain and welldeveloped sense organs.
Kingdom: Animalia
Systematic Position
Kingdom: Animalia
Subkingdom: Eumetazoa
Division: Triploblastica
Sbdivision: coelomates
Phylum: Annelida
Class: Oligochaeta
Genus: Allolobophora
(Earthworm)
Species: caliginosa
Allolobophora caliginosa
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All annelids (“little rings”) have segmented bodies.
Annelids live in the sea, most freshwater habitats,
and damp soil.
The coelom of the earthworm, a typical annelid, is
partitioned by septa, but the digestive tract,
longitudinal blood vessels, and nerve cords penetrate
the septa and run the animal’s length.
Most annelids, including earthworms, burrow in
sand and silt.
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The digestive
system consists of a
pharynx‫ء‬, an
esophagus, crop,
gizzard and
intestine
The closed
circulatory system
carries blood with
oxygen-carrying
hemoglobin
through dorsal and
ventral vessels
connected by
segmental vessels.
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In each segment is a
pair of excretory tubes,
metanephridia, that
remove wastes from
the blood and coelomic
fluid.
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Earthworms are
cross-fertilizing
hermaphrodites.
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Some earthworms
can also reproduce
asexually by
fragmentation followed
by regeneration.
Kingdom: Animalia
Systematic Position
Kingdom: Animalia
Subkingdom: Eumetazoa
Division: Triploblastica
Sbdivision: pseudocoelomates
Phylum: Nematoda
(Roundworms)
Class: Rhalditea
Order: Ascariida
Family: Ascariidae
Genus: Ascaris
Species: lumbricoides
Ascaris lumbricoides
Ascaris
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Roundworms are pseudocoelomates covered by tough cuticles
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Roundworms are found in most
aquatic habitats, wet soil, moist tissues
of plants, and the body fluids and
tissues of animals.
Some species parasitize animals.
They range in length from less than 1
mm to more than a meter.
The body of Nematode is covered with
a tough exoskeleton, the cuticle.
They have a complete digestive tract.
Nematodes usually engage in sexual
reproduction.
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The Summary