Bony fish - external anatomy
<div><span style="font-size:16px;"><b>PECTORAL FIN</b></span></div><div>Pectoral fins are used individually to turn the fish in either direction or control up and down movement. When used together, they act as brakes or allow the fish to swim backwards. Pectoral fins are absent in eels.</div><div><br></div><div><span style="font-size:16px;"><b>FINS</b></span></div><div>The fins of bony fishes are membranous and strengthened by a series of spines or soft rays. Unlike the rigid fins of sharks, the fins of most bony fishes can be folded flat against the body.</div>
<div><span style="font-size:16px;"><b>VENTRAL (PELVIC) FIN</b></span></div><div>The paired pelvic (or ventral) fins assist with balance and steering, including side-to-side and up and down movement, as well as acting as brakes to slow the fish down.</div>
<div><span style="font-size:16px;"><b>VENT</b></span></div><div>The vent, or anus, is the external opening to the digestive and reproductive systems.</div>
<div><span style="font-size:16px;"><b>ANAL FIN</b></span></div><div>The anal fin assists with stability, stopping the fish rolling from side to side.</div>
<div><span style="font-size:16px;"><b>DORSAL FIN</b></span></div><div>The dorsal fin acts like a rudder or keel on a boat, keeping the fish upright and stable. The dorsal fin can be split into two – the front spiny dorsal fin plays a role in protection, the second is known as the soft dorsal fin.</div>
<div><span style="font-size:16px;"><b>LATERAL LINE</b></span></div><div>The lateral line is a series of sensory pores, or receptors, which detect vibrations and pressure changes in the water.</div>
<div><span style="font-size:16px;"><b>SCALES</b></span></div><div>Bony fish have round, overlapping scales, although some species have lost their scales and have naked skin (e.g. toadfish, sunfish). Scales serve as a protective covering against bacterial infection and parasites. The skin also has thousands of mucous glands embedded in it. These secrete mucous that in turn provides an additional protective coating to the fish, makes it more streamlined for movement through the water and prevents any water leaking into the fishes’ body.</div>
<div><span style="font-size:16px;"><b>OPERCULUM</b></span></div><div>The operculum, or gill cover, is a hard bony plate that protects the gills. Bony fish have a single gill opening on either side of the head.</div>
<div>View bony fish – internal anatomy</div> TOUCH this image to discover its story. Image tagging powered by ThingLink
<div><span style="font-size:16px;"><b>NOSTRIL</b></span></div><div>Although fish don’t have a nose they do have nostrils (or nares) that are used to smell odours (such as chemicals) in the water.</div>
<div><b><span style="font-size:16px;">EYES</span></b></div><div>Bony fish have well developed eyes with almost 360° vision.Unlike sharks, bony fish do not have eyelids. Some fish species have false eye spots on their tails to confuse predators as to which end is which.Fish generally have good eyesight, but eye size does vary depending on habitat and behaviour.</div>
<div><span style="font-size:16px;"><b>MOUTH</b></span></div><div>Mouth shape and position often indicates what type of feeder the fish is e.g. upwards facing mouth indicates a surface feeder.The mouth is very important in ‘breathing’ (gas exchange), as water is taken into the mouth and passed over the gills, where oxygen is extracted and carbon dioxide is released.Bony fishes’ teeth are attached to their jaws.</div>
<div><span style="font-size:16px;"><b>CAUDAL FIN</b></span></div><div>The caudal fin or tail as it is more commonly known helps with steering, like the rudder on a boat. It also regulates the speed of forward movement.The caudal fin of bony fish is called a homocercal tail because both the upper and lower lobes are the same size (or symmetrical), unlike in sharks where the upper lobe is generally larger than the lower lobe (referred to as a heterocercal tail).Many bony fish move by bending their bodies so their tail finds thrust against the water.</div>
<div><span style="font-size:16px;"><b>FISH CHATTER</b></span></div><div>Fish produce sounds by rubbing together two bony parts of the body, such as their teeth or spines.</div>
<div><span style="font-size:16px;"><b>MASTERS OF DISGUISE</b></span></div><div>Unlike sharks, many bony fish have bright colours and patterns. Fish that live on the sea floor often have flattened bodies, usually camouflaged in mottled, neutral colours.</div> Marine WATERs, Hillarys, Australia. 653 likes. Marine WATERs welcomes you to share experiences and knowledge with other like-minded marine educators across Western Australia, Australia and overseas.
<div>More education resources are available from the MarineWATERs website.</div> Marine WATERs
<div>Find out more about the Australian herring's diet, lifecycle, distribution and fishing for them at this link.</div> Herring, Australian

This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Terms of Service and Cookie Policy. Your use of ThingLink's Products and Services, is subject to these policies and terms.