Animal Phyla Identification

Porifera

Examples: Sponge

Evolutionary Distinction: Parazoa (No Tissues)

Characteristics: Lack true tissues and organs, asymmetrical, adapted to consume organisms that flow through their body via water, sessile metazoans (multi celled immobile animals)

Germ Layers: No true germ layers

Symmetry: Asymmetrical

Development Type: Neither deuterostome or protostome. Asexual and sexual reproduction. Asexually they bud off new individuals. Sexually they release sperm and eggs into the water.

Cnidaria

Examples: Jellyfish, Corals, Sea Anemones, Hydroids

Evolutionary Distinction: Eumetazoa (Specialized Tissues), Radiata (Radial Symmetry, Diploblastic) 

Characteristics: radial symmetry, somewhat organized body plan but no organs, hollow tentacles, two forms: polyps and medusa, regeneration. Cnidocytes used to capture prey

Germ Layers: two, diploblastic

Symmetry: Radial 

Development Type: Neither deuterostome or protostome. Sexual reproduction, asexual reproduction. 

Echinoderms

Examples: Starfish, Sea Urchins, Sand Dollars, Sea Cucumbers, Sea Lilies

Evolutionary Distinction: Bilateria (Bilateral Symmetry, Triploblastic), Possesses body cavities, Deuterostome 

Characteristics: Water vascular system, external tube feet, calcareous endoskeleton. 

Germ Layers: Triploblastic, Three layers

Symmetry: Bilateral

Development Type: Deuterostome

Vertebrata

Examples: Humans, Mammals, Reptiles, Birds, Amphibians

Evolutionary Distinction: Bilateria (Bilateral Symmetry, Triploblastic), Possesses body cavities, Deuterostome 

Characteristics: Backbone, pharyngeal slits, post-anal tail, endostyle.

Germ Layers: Three, Triploblastic 

Symmetry: Bilateral

Development Type: Deuterostome 

Mollusca

Examples: Octopus, Squid, Snail, Slugs, Abalone 

Evolutionary Distinction: Protostomia, Lophotrochozoa 

Characteristics: “limpet-like” shell, unsegmented, “foot” organ that has various uses.

Germ Layers: Three, Triploblastic

Symmetry: Bilateral 

Development Type: Protostome

Annelida

Examples: Segmented Worms, Earthworms, Leeches

Evolutionary Distinction: Protostomia, Lophotrochozoa 

Characteristics: Segmented: each segment has repeated organs over and over again. 

Germ Layers: Three, Triploblastic

Symmetry: Bilateral

Development Type: Protostome

Platyhelminthes

Examples: Flatworms

Evolutionary Distinction: Protostomia, Lophotrochozoa 

Characteristics: Flattened, 80% of species are parasites, acoelomate, triangular head, no respiratory system, incomplete digestive system. 

Germ Layers: Three, Triploblastic

Symmetry: Bilateral

Development Type: Protostome

Nematoda

Examples: Nematodes, roundworm, whipworm, 

Evolutionary Distinction: Ecdysozoa

Characteristics: Unsegmented, cylindrical, sexually dimorphic, tubular digestive systems with openings at mouth and anus 

Germ Layers: Three, Triploblastic

Symmetry: Bilateral

Development Type: Protostome

Arthropoda

Examples: Insects, crustaceans, arachnids 

Evolutionary Distinction: Ecdysozoa

Characteristics: exoskeleton, jointed legs, cuticles made of chitin, segments.

Germ Layers: Three, Triploblastic

Symmetry: Bilateral

Development Type: Protostome

Rotifera

Examples: “wheel animals”, Brachionus plicatilis, Rotaria neptunia

Evolutionary Distinction: Lophotrochozoan

Characteristics: Corona, Mastax, Body plan is broken up into three sections: head, trunk and foot.
Germ Layers: Three, Triploblastic
Symmetry: Bilateral

Development type: Protostome