Intro. to the 10 Major Animal Phyla

What are the ten major phyla in the Animal Kingdom?Intro. to the 10 Major Animal PhylaPhylum PoriferaComposed of spongesAbout 10,000 species.Considered to be the 1st group of animals on Earth. Sponge body even contains cells that resemble protists.

Choanocytes

Phylum PoriferaFound in either fresh or marine water.Lack organs and symmetryShapes may be like cups, fans, crusts, or tubes

Haliclona oculata

Red barrel sponge (also known as Xestospongia)Phylum PoriferaSome species are large as barrels.Sponge body pierced by pores (Porifera), through which they feed by circulating water. (filter feeding)

Phylum PoriferaReproduction is both asexual and sexual.Larval stage free-swimming, adults are sessile.Bath sponges were once living sponges.

Phylum Cnidaria (stinging-celled animals)Includes jellyfish, sea anemones, corals, and Portuguese man-of-war.Considered to be the 2nd big group of animals to have evolved.

Elkhorn CoralPhylum Cnidaria (stinging-celled animals)First animal group with organs level of organization.Saclike bodies include mouth surrounded by tentacles that sting and paralyze prey.Almost all are marine.

Phylum Cnidaria (stinging-celled animals)About 10,000 species.Have radial symmetryCertain species alternate between a polyp and medusa form; others may spend lives as either polyps or medusas.

Phylum Cnidaria (stinging-celled animals)A man-of-war is a floating colony of many cnidarian animals in the polyp form, which live and work together.

Phylum Ctenophora Composed of tiny, jelly-fish animals called comb jellies.About 50 or so species.Do not sting.

Comb jelliesSea gooseberryPhylum Ctenophora Colorless, transparent; although many employ bioluminescence.Have 8 rows of cilia along their bodies, which they use for locomotion.Principal food for sea turtles.

Phylum PlatyhelminthesIncludes all flat (platy) worms.About 15,000 species.Were the first bilaterally symmetrical animals on Earth.

Phylum PlatyhelminthesSome species are free-living (e.g. Planaria), but most are parasitic (tapeworms and flukes).

Phylum NematodaComposed of worms that have round bodies.Have complete digestive systems with mouth(s) and separate anus(es).About 80,000 species.

Phylum NematodaSome are parasites, including Ascaris and heartworms.Majority live in soil and are not parasites.

Phylum AnnelidaComposed of worms whose bodies are divided into segments.Examples: Earthworms, leeches, and many beautiful marine worms.

Phylum AnnelidaAbout 12,000 species.Have what is called a closed circulatory system comparable to that found in advanced animals.

Phylum MolluscaIncludes soft-bodied animals such as clams, oysters, snails, octopuses, and squids.About 110,000 species.

Phylum MolluscaPhylum is divided into 3 main classes:Bivalvia (rigid shell of 2 parts) clams, oysters, mussels, and scallopsGastropod (large, muscular foot attached to their stomach) snails, slugs, and whelksCephalopods (large head) conches, octopuses, squids, and nautiluses.

Phylum ArthropodaLargest phylum in Animal Kingdom.About 100,000 species known at present.Composed of animals that have a segmented body with a hard outer covering (exoskeleton) and appendages that are jointed.

Phylum Arthropoda5 main classes:Crustacea lobsters, crabs, crayfish, barnacles, and shrimp.Arachnida spiders, ticks, mites and scorpions.Insecta flies, ants, beetles, fleas, lice, bees, and roaches.

Phylum ArthropodaChilopoda centipedes (have 1 pair of legs per body segment).Diplopoda millipedes (have 2 pairs of legs per body segment).

Phylum EchinodermataComposed of animals whose skin is covered with spines.Includes sea stars (starfish), sea urchins, sea cucumbers, and sand dollars.About 6,000 species. All are marine.

Phylum EchinodermataLarvae display bilateral symmetry; adults radial symmetry.Have an internal skeleton.Many can regenerate lost parts.

Phylum ChordataBest known of all the phyla.Just under 45,000 known species.At some stage of development, all chordates have: a notochord (a flexible rod of cartilage in the back), a nerve cord, and paired gill slits in the throat cavity.

Phylum ChordataThe phylum is divided into 3 subphyla:Subphylum Urochordata soft, saclike, marine animals called tunicates or sea squirts.Subphylum Cephalochordata small, fishlike, marine animals called lancelets.Subphylum Vertebrata all the different vertebrate animals (7 classes). Vertebrate animals replace the notochord with a backbone during embryonic development.

Phylum ChordataThe 7 classes of vertebrate animals:Class Agnatha the jawless fishes such as lampreys and hagfish.Class Chondrichthyes the cartilaginous fishes such as sharks.Class Osteichthyes the bony fishes such as perches and trouts.Class Amphibia frogs, toads and salamandersClass Reptilia turtles, crocodiles, alligators, snakes and lizards.Class Aves the birds.Class Mammalia the mammals.