Jellyfish, Sponges, and Other Simple Animals

Jaw Animals: Micrognathozoa - Physical Characteristics, Behavior And Reproduction, Conservation Status - GEOGRAPHIC RANGE, HABITAT, DIET, JAW ANIMALS AND PEOPLE

Gnathostomulids: Gnathostomulida - Physical Characteristics, Red Haplognathia (haplognathia Ruberrima): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, BEHAVIOR AND REPRODUCTION, GNATHOSTOMULIDS AND PEOPLE, CONSERVATION STATUS

Gnathostomulids live all over the world but mainly in the northern part of the Atlantic Ocean and the southern part of the Pacific Ocean. Gnathostomulids live on sheltered beaches, near sea grasses and mangroves, and between coral reefs. Gnathostomulids graze on bacteria and threads of fungus attached to sand grains. Gnathostomulids glide between sand grains. They contract when disturbed. Som…

Priapulans: Priapulida - Physical Characteristics, Behavior And Reproduction, No Common Name (priapulus Caudatus): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, PRIAPULANS AND PEOPLE, CONSERVATION STATUS

Girdle Wearers: Loricifera - Physical Characteristics, Behavior And Reproduction, Bucket-tailed Loriciferan (rugiloricus Cauliculus): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, GIRDLE WEARERS AND PEOPLE, CONSERVATION STATUS

Wheel Wearers: Cycliophora - Physical Characteristics, Behavior And Reproduction, Conservation Status - GEOGRAPHIC RANGE, HABITAT, DIET, WHEEL WEARERS AND PEOPLE

Sea Lilies and Feather Stars: Crinoidea - Physical Characteristics, Behavior And Reproduction, Orange Sea Lily (nemaster Rubiginosa): Species Accounts, West Atlantic Stalked Crinoid (endoxocrinus Parrae): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET

Sea lilies and feather stars live in the western part of the Pacific Ocean and on both sides of the Atlantic Ocean. Most sea lilies live in deep water, and most feather stars live on coral reefs. Both animals usually live on hard surfaces. Sea lilies and feather stars eat plankton and waste. Plankton is microscopic plants and animals drifting in water. Sea lilies and feather stars have no kno…

Sea Stars: Asteroidea - Physical Characteristics, Behavior And Reproduction, Sea Stars And People, Sand Star (astropecten Irregularis): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, CONSERVATION STATUS

Sea stars live in the Pacific, Atlantic, and Indian oceans, including the Antarctic regions. Sea stars live in the sea from the shore to the deepest ocean. They live in sea grass beds, under rock rubble, on coral reefs and rocky underwater cliffs, and in sand and mud. Sea stars eat anything that is too slow to escape, such as mollusks, crustaceans, sponges, worms, and even other sea stars and…

Sea Daisies: Concentricycloidea - Physical Characteristics, Behavior And Reproduction, Medusiform Sea Daisy (xyloplax Medusiformis): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, SEA DAISIES AND PEOPLE, CONSERVATION STATUS

Brittle and Basket Stars: Ophiuroidea - Physical Characteristics, Behavior And Reproduction, Dwarf Brittle Star (amphipholis Squamata): Species Accounts, Tropical Brittle Star (ophiactis Savignyi): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, BASKE

Brittle and basket stars live in all the oceans of the world. Some brittle and basket stars burrow into muddy or sandy sea bottoms. Others live on or among algae, sponges, and coral. Algae (AL-jee) are plantlike growths that live in water and have no true roots, stems, or leaves. Some brittle and basket stars eat sea animals, alive or dead. Others eat particles from the bottom or from the ope…

Sea Urchins and Sand Dollars: Echinoidea - Physical Characteristics, Behavior And Reproduction, Sea Urchins, Sand Dollars, And People, Long-spined Sea Urchin (diadema Savignyi): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, CONSERVATION STATUS

Sea urchins and sand dollars live all over the world. Sea urchins live on wave-exposed rocks, in crevices within rocks, in rock pools, on coral reefs, in sandy lagoons, in sea grass beds, and in kelp forests. Sand dollars live in sand and coarse gravel. Some sea urchins eat only algae, sea grass, and seaweed. Algae (AL-jee) are plantlike growths that live in water and have no true roots, stem…

Sea Cucumbers: Holothuroidea - Physical Characteristics, Behavior And Reproduction, Sea Cucumbers And People, Candy Cane Sea Cucumber (thelenota Rubralineata): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, CONSERVATION STATUS

Arrow Worms: Chaetognatha - Physical Characteristics, Behavior And Reproduction, No Common Name (pterosagitta Draco): Species Accounts, No Common Name (eukrohnia Fowleri): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, ARROW WORMS AND PEOPLE, CONSERV

Arrow worms live in all the oceans of the world. Arrow worms live in every part of the ocean. Most drift in open water close to the surface. Bottom-dwelling species live attached to objects such as sea grass and rocks. Arrow worms eat plankton, including tiny crustaceans, fish larvae, and other arrow worms. Digestion is rapid. Scientists believe each arrow worm eats two to fifty prey animals …

Hemichordates: Hemichordata - Physical Characteristics, Behavior And Reproduction, Hawaiian Acorn Worm (ptychodera Flava): Species Accounts, Spaghetti Worm (saxipendium Coronatum): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, HEMICHORDATES AND PEOP

Sea Squirts: Ascidiacea - Physical Characteristics, Behavior And Reproduction, No Common Name (distaplia Cylindrica): Species Accounts, No Common Name (botryllus Schlosseri): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, SEA SQUIRTS AND PEOPLE, CONS

Sea squirts live in all oceans and seas. Sea squirts live at all depths. Most live in shallow water. Some even survive on open shores under strong wave action. Some sea squirts live in ocean trenches as deep as 28,000 feet (8,400 meters). Most species of sea squirts live on rocks, shells, or algae (AL-jee), which are plantlike growths that live in water and have no true roots, stems, or leave…

Salps: Thaliacea - Behavior And Reproduction, Salps And People, Pyrosome (pyrosoma Atlanticum): Species Accounts, Salp (thalia Democratica): Species Accounts - PHYSICAL CHARACTERISTICS, GEOGRAPHIC RANGE, HABITAT, DIET, CONSERVATION STATUS

Larvaceans: Appendicularia - Physical Characteristics, Behavior And Reproduction, No Common Name (oikopleura Labradoriensis): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, LARVACEANS AND PEOPLE, CONSERVATION STATUS

Sorberaceans: Sorberacea - Physical Characteristics, Behavior And Reproduction, No Common Name (oligotrema Sandersi): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, SORBERACEANS AND PEOPLE, CONSERVATION STATUS

Lancelets: Cephalochordata - Physical Characteristics, Behavior And Reproduction, Lancelets And Vertebrates, Florida Lancelet (branchiostoma Floridae): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, CONSERVATION STATUS

Jellyfishes Sponges - Species List by Biome

Canine heartworm Giant thorny-headed worm Mermis nigrescens Moniliformis moniliformis Aequorea victoria Black coral Blue starfish Botryllus schlosseri Bucket-tailed loriciferan Candy cane sea cucumber Convulutriloba longifissura Crown-of-thorns Deep water reef coral Desmoscolex squamosus Dicyemodeca deca Didemnum studeri Distaplia cylindrica Distichopora violacea Dwarf brittle star Eukrohnia fowle…

Species List by Geographic Range

Asplanchna priodonta Canine heartworm Dactylogyrus vastator Dog tapeworm Fasciola hepatica Giant thorny-headed worm Human blood fluke Lancet fluke Lepidodermella squamata Limnognathia maerski Oerstedia dorsalis Paragordius varius Polystoma integerrimum Proteocephalus longicollis Rat lungworm Asplanchna priodonta Bucket-tailed loriciferan Canine heartworm Convolutriloba longifissura Dactylogyrus va…

Jellyfishes Sponges: Pronunciation Guide for Scientific Names

Acanthaster planci ah-KAN-thuh-ster PLANK-eye Acanthocephala ah-KAN-thoh-sef-fal-ay Acoela ah-KOHL-ay Adenophorea ah-den-oh-FOR-ee-ay Aequorea victoria ee-KWOR-ee-ay vik-TOR-ee-ay Aglantha digitale ah-GLAN-thay dih-jih-TAL-ee Amphipholis squamata am-fee-FOH-lihs SKWAH-mah-tay Angiostrongylus cantonensis an-jee-oh-STRON-jih-lus kan-ton-EN-sis Anthozoa an-tho-ZOH-ay Antipathella fiordensis an-tih-PA…

Jellyfishes Getting to Know Corals Sponges and Other Simple Animals

An animal is a living thing made up of many cells and it is not a plant. Simple animals are those without a fluid-filled body cavity between the outer body wall and the digestive tract. Examples of simple animals are sponges, corals, jellyfishes, sea stars, sea urchins, roundworms, and flatworms such as tapeworms. All simple animals are invertebrates (in-VER-teh-brehts), meaning they do not have a…

Sponges: Porifera - Physical Characteristics, Behavior And Reproduction, No Common Name (soleneiscus Radovani): Species Accounts, Bird's Nest Sponge (pheronema Carpenteri): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, SPONGES AND PEOPLE, CONSERVATI

Sponges live all over the world. Most sponges live in the sea, but a few species live in freshwater. Many sponges live on reefs. Most sponges need a firm surface on which to attach, such as rocks or the skeletons of dead sponges and coral. Other sponges live on sand or mud at the bottom of the deep sea. Freshwater sponges live in lakes and streams. Sponges eat tiny particles such as bacterial…

Placozoans: Placozoa - Physical Characteristics, Behavior And Reproduction - GEOGRAPHIC RANGE, HABITAT, DIET, PLACOZOANS AND PEOPLE, CONSERVATION STATUS

Scientists do not know whether placozoans are widely distributed around the world. These animals are so hidden that their diversity may be much greater than scientists realize. The placozoans that have been studied are samples cultured in laboratory aquariums near warm seas. Scientists do not know where placozoans live under natural conditions. They may live on the surface of underwater rocks…

Salinella: Monoblastozoa - Physical Characteristics, Behavior And Reproduction - GEOGRAPHIC RANGE, HABITAT, DIET, SALINELLA AND PEOPLE, CONSERVATION STATUS

Rhombozoans: Rhombozoa - Physical Characteristics, Behavior And Reproduction, No Common Name (dicyemodeca Deca): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, RHOMBOZOANS AND PEOPLE, CONSERVATION STATUS

Orthonectidans: Orthonectida - Physical Characteristics, Behavior And Reproduction, No Common Name (rhopalura Ophiocomae): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, ORTHONECTIDANS AND PEOPLE, CONSERVATION STATUS

Orthonectidans live in the coastal regions of the northwestern part of the Atlantic Ocean and the Mediterranean Sea, the northwestern part of the Pacific Ocean near Japan, and the northeastern part of the Pacific Ocean along the coast of the United States. Orthonectidans live in the tissues of sea-dwelling invertebrates, such as flatworms; segmented worms; mollusks (MAH-lusks), or animals wit…

Anemones and Corals: Anthozoa - Physical Characteristics, Diet, Behavior And Reproduction, Anemones, Corals, And People, Giant Green Anemone (anthopleura Xanthogrammica): Species Accounts - GEOGRAPHIC RANGE, HABITAT, CONSERVATION STATUS

Hydroids: Hydrozoa - Physical Characteristics, Behavior And Reproduction, Fire Coral (millepora Alcicornis): Species Accounts, No Common Name (distichopora Violacea): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, HYDROIDS AND PEOPLE, CONSERVATION ST

Hydroids live all over the world. Hydroids live in all water habitats, from sea caves to deep-sea trenches, from lakes and ponds to rocky coasts and between grains of sand. Hydroid polyps and medusae feed on almost all animals, from plankton, or microscopic plants and animals drifting in water, to fish. The medusae of hydroids prey on the eggs and larvae of fish that people need for food. Som…

Box Jellies: Cubozoa - Behavior And Reproduction, Sea Wasp (chironex Fleckeri): Species Account - PHYSICAL CHARACTERISTICS, GEOGRAPHIC RANGE, HABITAT, DIET, BOX JELLIES AND PEOPLE, CONSERVATION STATUS

Box jellies have a cube-shaped body, or bell, also called an umbrella. The mouth is inside the bell. Tentacles are attached to each of the four lower corners of the bell. Some box jellies have several tentacles attached to each corner, and others have only one tentacle at each corner. A structure near the base of the bell contains one balance organ and six eyes. Box jellies live in warm coast…

Jellyfish: Scyphozoa - Physical Characteristics, Behavior And Reproduction, Jellyfish And People, Sea Nettle (chrysaora Quinquecirrha): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, CONSERVATION STATUS

Comb Jellies: Ctenophora - Physical Characteristics, Behavior And Reproduction, Venus's Girdle (cestum Veneris): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, COMB JELLIES AND PEOPLE, CONSERVATION STATUS

Acoels: Acoela - Physical Characteristics, Behavior And Reproduction, No Common Name (convolutriloba Longifissura): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, ACOELS AND PEOPLE, CONSERVATION STATUS

Turbellarians: Turbellaria - Physical Characteristics, Habitat, Diet, Behavior And Reproduction, Freshwater Planarian (dugesia Tigrina): Species Accounts - GEOGRAPHIC RANGE, TURBELLARIANS AND PEOPLE, CONSERVATION STATUS

Flukes: Trematoda - Physical Characteristics, Behavior And Reproduction, Lancet Fluke (dicrocoelium Dendriticum): Species Accounts, Human Blood Fluke (schistosoma Mansoni): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, FLUKES AND PEOPLE, CONSERVATIO

Flukes live all over the world. The habitat of a fluke is the same as that of its host and can change as the fluke goes from host to host. Flukes cannot live without nourishment from a host organism. In some species the larvae (LAR-vee), or animals in an early stage that change form before becoming adults, do not eat. Adult flukes eat blood cells, mucus, and body cells. Flukes pose a health t…

Monogeneans: Monogenea - Physical Characteristics, Behavior And Reproduction, No Common Name (dactylogyrus Vastator): Species Accounts, No Common Name (polystoma Integerrimum): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, MONOGENEANS AND PEOPLE, CO

Tapeworms: Cestoda - Physical Characteristics, Habitat, Behavior And Reproduction, Tapeworms And People, Broad Fish Tapeworm (diphyllobothrium Latum): Species Accounts - GEOGRAPHIC RANGE, DIET, CONSERVATION STATUS

Anoplans and Enoplans: Nemertea - Physical Characteristics, Behavior And Reproduction, Anoplans, Enoplans, And People, No Common Name (oerstedia Dorsalis): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, CONSERVATION STATUS

Anoplans and enoplans live all over the world. Most anoplans and enoplans live in the sea near shore— anoplans on soft bottoms and enoplans among algae. Algae (AL-jee) are plantlike growths that live in water and have no true roots, stems, or leaves. Some species live in deep, open water. A few species live in freshwater or on land. The land-dwelling species usually live on tropical is…

Rotifers: Rotifera - Physical Characteristics, Behavior And Reproduction, No Common Name (asplanchna Priodonta): Species Accounts, No Common Name (seison Nebaliae): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, ROTIFERS AND PEOPLE, CONSERVATION STAT

Rotifers live all over the world. Most rotifers live in freshwater in sand or mud at the bottom, in plants, or in open water. Several species live in saltwater, usually among plants but sometimes between grains of sand on beaches. Rotifers eat algae and other protists, bacteria, and even other rotifers. Algae (AL-jee) are plantlike growths that live in water and have no true roots, stems, or …

Gastrotrichs: Gastrotricha - Physical Characteristics, Behavior And Reproduction, No Common Name (lepidodermella Squamata): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, GASTROTRICHS AND PEOPLE, CONSERVATION STATUS

Kinorhynchs: Kinorhyncha - Physical Characteristics, Behavior And Reproduction, No Common Name (echinoderes Sensibilis): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, KINORHYNCHS AND PEOPLE, CONSERVATION STATUS

Roundworms: Adenophorea - Physical Characteristics, Roundworms And People, No Common Name (desmoscolex Squamosus): Species Accounts, No Common Name (mermis Nigrescens): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, BEHAVIOR AND REPRODUCTION, CONSERV

Roundworms live all over the world. Roundworms live in water and soil everywhere except the desert. A few species are parasites of plants and animals. Parasites (PAIR-uh-sites) are animals or plants that live on or in other animals or plants, or hosts, without helping them and usually harming them. Most roundworms eat bacteria, fungi, and tiny growths in the soil. The parasite species feed on…

Secernenteans: Secernentea - Physical Characteristics, Behavior And Reproduction, Secernenteans And People, Canine Heartworm (dirofilaria Immitis): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, CONSERVATION STATUS

Hair Worms: Nematomorpha - Physical Characteristics, Behavior And Reproduction, No Common Name (paragordius Varius): Species Account - GEOGRAPHIC RANGE, HABITAT, DIET, HAIR WORMS AND PEOPLE, CONSERVATION STATUS

Hair worms live all over the world except Antarctica. One type of hair worm lives in sea animals such as crabs and shrimp. The other type lives in insects such as crickets, grasshoppers, and beetles. The worms that live in insects usually are found in slow-moving freshwater streams or ponds. In streams the worms are either attached to plants hanging over the banks or live between rocks on the…

Thorny-Headed Worms: Acanthocephala - Physical Characteristics, Behavior And Reproduction, Thorny-headed Worms And People, No Common Name (moniliformis Moniliformis): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, CONSERVATION STATUS

Entoprocts: Entoprocta - Behavior And Reproduction, Marine Colonial Entoproct (barentsia Discreta): Species Account - PHYSICAL CHARACTERISTICS, GEOGRAPHIC RANGE, HABITAT, DIET, ENTOPROCTS AND PEOPLE, CONSERVATION STATUS