Actinopterygii

Actinopterygii(Ray-Finned Fishes)

Bradley Gregg, Megan MacMillan, Jessica Oakley, Cardy Saunders1

ActinopterygiiBackgroundActinopterygii Ray-Finned FishesMost diverse taxa of fishes on Earth

Half of all vertebrates24,000 species

Commonly referred to as the ray-finned fishes and belonging to the superclass Osteichthyes which encompasses all bony fish, Actinopterygii is the largest and by far the most diverse group of fishes in the world today. Indeed, it comprises approximately half of all living vertebrates, with an estimated twenty-four thousand species within its taxon, in four-hundred-thirty-one families in forty-two orders.It is divided into two subclasses2Two SubclassesChondrostei: cartilaginous fishes

Neopterygii: new fin fishes

SturgeonClown FishChondrostei; fish that are mainly cartilaginous, though showing some ossification, such as the Sturgeon; and Neopterygii; (literally meaning new fins) which characterize major improvements over other fish, including greater control over fin movement, thereby leading to improved swimming capabilities, like the Clown Fish.

3Characteristics Fins composed of bony rays with webbing

Sensory arrays along each side

Lateral LineRay-finned fish, as the name suggests, are characterized by possessing fins that are composed of many thin, bony, parallel rays with webbings of tissue connecting them. Being so thin, the fins themselves contain little or no muscle, and are moved instead by muscles within the main body of the fish. The ray-finned fishes display another unique feature of anatomy; the lateral line, shown here on this Crucian Carp: This is a long canal running down each side of the fish that contains specialized sensory receptors capable of detecting water currents. These receptors provide the fish with spatial awareness, which contributes to navigation and orientation, particularly when schooling.

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Nile Tilapia

Scorpion Fish

Alaska BlackfishRay-finned fish have staggering diversity in the looks department, with appearances ranging from the sleek and elegantly streamlined form of the Nile Tilapia; to the artistically bizarre, yet well camouflaged Scorpion Fish; to the small and slightly elongated Alaska Blackfish.5Ocean Sunfish (Mola mola)

Giant Oarfish

Paedocypris progenetica

They also have an impressive range of sizes: The Giant oarfish, sometimes referred to as the king of herrings, is by far the longest bony fish yet discovered, and is capable of growing to extreme lengths upwards of seventeen metres, unlike the much smaller specimen shown here.The Ocean sunfish (also known as the Mola mola), is the heaviest known bony fish, with an average adult body weight of one-thousand kilograms. Paedocypris progenetica is the smallest known fish species in the world, at the tiny length of ten millimetres, fully grown. 6EvolutionEarliest fossils from 420-360 million years ago

Dominant aquatic vertebrates: 300 million years ago

Based on the fossil record, ray-finned fishes made their first appearance in the Devonian period, also known as the age of the fishes, around four-hundred million years prior to present day. However, it took until forty million years later for them to become dominant in freshwater areas and for them to begin their diversification into the seas. By the end of the Paleozoic era, some two-hundred-forty million years ago, these creatures were easily the most dominant of all aquatic vertebrates. 7HabitatsFreshwater rivers and subterranean caves:

Light, open ocean and dark, deep ocean:

Freezing Antarctic, tropical coral reefs:

TroutAtlantic Blue Marlin

Angler Fish

Antarctic Ice Fish

Parrotfish

Ozark CavefishRay-finned fishes inhabit a vast variety of environmental extremes; from freshwater lakes, rivers, and streams; to pitch-black subterranean cave systems; from clear expanses of open ocean, to the darkest depths of the deep ocean; from the grey, freezing Antarctic waters to the balmy, colourful tropical coral reefs. Members of this amazingly diverse taxa can be found practically in any location where there is water.8Fin.Thank you for watching. At this time we would like to give credit where it is due. The following is a complete list of sources utilized in the creation of this presentation.Information/Research:www.animaldiversity.ummz.umich.edu //University of Michigan Animal Diversity//www.ucmp.berkeley.edu//University of California Museum of Paleontology//www.itis.gov//Integrated Taxonomic Information System//www.en.wikipedia.org//Wikipedia//www.tolweb.org//Tree of Life web project// www.seawater.no//The Marine Flora and Fauna of Norway//Images:www.imgt.com//taxonomic tree//www.tolweb.com//Sturgeon image//www.creationguide.com//Clownfish image//www.talkrational.org//Yellowtail Snapper skeleton image//www.bbc.co.uk//fish fin image//www.farnhamanglingsociety.com//Crucian Carp image//www.lakeharvest.com//Nile Tilapia image//www.canadianprincess.com//Scorpion Fish image//www.beauty-animal.blogspot.com//Alaska Blackfish image//www.wafflesatnoon.com//Giant Oarfish image//www.baligreatadventure.net//Ocean Sunfish image//www.newscientist.com//Paedocypris Progenetica image//www.fossil-facts-and-finds.com//fish fossil image//www.online.sfsu.edu//Trout image//www.ruethedayblog.com//Ozark Cavefish image//www.carnivoraforum.com//Atlantic Blue Marlin image//www.anglerfish.info//Angler Fish image//www.ichthyologist.tumblr.com//Antarctic Ice Fish image//www.students.cis.uab.edu//Parrotfish image//

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