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Class Osteichthyes (Greek, Osteon = bone, ichthyes = fish). The bony fish are the most diverse class of vertebrates. They comprise more than 95% of all fish and 50% of all species of vertebrates.
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Class Osteichthyes(Greek, Osteon = bone, ichthyes = fish). The bony fish are the most diverse class of vertebrates. They comprise more than 95% of all fish and 50% of all species of vertebrates. Bony fish skeleton is made of bone, which is an important characteristic. Other structural feature in bony fish is a flap called the operculum (a flap on each side of the head that covers the gills). The movements of these flaps allow the fish to breathe without moving. Most bony fish are carnivorous, few are herbivores that feed on algae and aquatic plants, and some are filter feeders. Bony fish are all aquatic and majorities are marine (salt water) such as salmon, sea horse, blowfish, and sea bass. Gold fish, beta, rainbow trout are few examples of fresh water fish.
Class:Osteichthyes These are the bony fishes, by far the largest group of vertebrates today in terms of species numbers (about 25,000). The major group are the ray-finned fishes, which include all the animals we commonly call fish with their extraordinary diversity from tiny coral denizens, to strange apparitions like seahorses, to truly bizarre denizens of the deep oceans like lanternfish, to huge predators like tuna and swordfish. These are the first vertebrates with bones replacing cartilage, with about 50 different bones forming the skull around the brain. They are also characterized by the rays that support their fins, always present as paired pectoral and pelvic fins, multiple dorsal fins, a ventral anal fin, and of course the tail fin. Other adaptations involve complex circulatory systems through their gill slits involving counter currents for respiration and a swim bladder for regulating bouyancy.
Class Osteichthyes: (Tuna, Carp, Salmon, and Sturgeons). General Characteristics: - Abundant in oceans and fresh water -Skeleton made of bone -Lateral line -Two chambered heart -Operculum covering the gills. -Swim bladder -Ectothermic -Paired fins made of rays and spines,or lobed fins lacking the rays and spines. -Various types of scales (ctenoid,ganoid, or cycloid). -Marine and fresh water species. -Gills used for respiration
-External fertilization. Spawning. Oviparous. • -No external ears • -No eye lids. • Ray-finned fish – familar modern fish • Lobe-finned fish - coelocanths, muscular fins may have enabeled fish to ‘walk’ • Lung fish – retained lungs
Class Osteichthyes Mouth Complex and adaptable
Class Osteichthyes Gill cover
Class Osteichthyes Buoyancy
Body form and niche seahorse
Class Osteichthyes bony fishes
Class:Amphibia • (amphi = on both sides, double; bios = life) is frogs, newts, and salamanders. They were the first land vertebrates. Frogs, especially, go through metamorphosis. Their eggs have no egg shells, so the sperm can swim through the water to the eggs, and the embryos must develop in water. Oldest class of tetrapods • 4000 extant species of frogs, salamanders and caecilians • Thought to have evolved from lobe-finned fishes • Molecular data suggests closer relationship to lungfishes • Early amphibians aquatic, coming to land to feed • Order Urodela (salamanders) • Order Anura (frogs and toads) • Order Apoda (caecilians)
Class Amphibia • First vertebrates to inhabit land • Most are 4 limbed (tetrapods) • Include frogs, salamanders & caecilians • Have 3 chambered heart • Have more complicated gas exchange organs (often a combination of lungs, gills and skin)
Urodeles Salamanders retain their tails as adults, some are entirely aquatic, others live on land. • 400 species, aquatic and terrestrial • Walk side to side or swim sinusoidally
Order Urodela(Salamanders & Newts) • Urodela ("tailed ones" - Salamanders) • More dependent on water • Many species possess gills as adults
Anurans Poison Arrow Frog Buggy-Eyed Tree Frog • 3500 species, adapted to land • Metamorphosis, air breathing lungs
Apodans • Legless, blind, • burrowing The caecilians include about 165 limbless amphibians that inhabit tropical forests of South America, Africa and Southeast Asia. Because they are entirely aquatic or burrowing organisms, they are seldom seen by humans. Their food consists mostly of earthworms and other small invertebrates. Fertilization in caecilians is internal, and the male is equipped with a protrusible copulatory organ. Viviparity (live birth) is also seen in some caecilians, with the embryos obtaining nourishment by eating the wall of the oviduct of the mother!
Common North American Frogs North American Toad Green Frog Bullfrog Poison Arrow Frog Leopard Frog Peepers
Reproduction • Lack internal fertilization & amniotic eggs • Reproduction must occur in H2O • Most species undergo metamorphosis • Larval stage (tadpole) is usually an aquatic herbavore • Lacks legs, respiration is through gills • Develops into tetrapod adult (usually carnivorous)
