What is the difference between ray-finned fish and the lobe-finned fish?

Question

any difference?

Answer 1

The lobe-finned fish refer to all the members of the group Sarcopterygii with the exception of the tetrapods. As their name suggests, the fins of lobe-finned fish are supported by a central appendage composed of bones and muscles, potentially useful for supporting the body on land, as in modern lungfish. Most members of this group are extinct, but the few living species have adapted to different extreme conditions. The lungfishes of South America and Africa burrow into the mud when their ponds or pools dry up, and the coelacanths live at depths of 100-400 meters in the Indian Ocean.

Ray-finned fish (Actinopterygii) are the dominant aquatic vertebrates today. They illustrate great diversity in their morphology and habitats, living in shallow to deep and freshwater to marine habitats. Their name comes from the presence of “rays,” fine bony or horny spines that support the webbing of their fins. Trout, salmon, bass, and tuna are typical modern ray-finned fish.

Answer 2

Lobe Finned Fish

Answer 3

The Sarcopterygians are the so-called lobe-finned fishes. Do not be confused, just because they aren't called ray-finned fishes does not mean that their fins do not have lepidotrichthia (rays) because they certainly do. The difference between the two fins is that the lobe-fin has the bones and the muscles that operate the fin mostly on the outside of the body (think about how our arm muscles work).

Answer 4

Well, the primary difference between the ray-finned (Actinopterygii) and lobe-finned (Sarcopterygii) fish is the fact that lobe-finned fish have a fleshy lobe at the base of their fin. There are other differences in scale structure, skeletal morphology and such, but they're not as important from an evolutionary history point-of-view.

The lobe possesses musculature and skeletal elements, which the Sarcopterygians can use to power their fins with greater strength and provide more support than the ray-finned fish can. Thus, they can use their fins to scull with great maneuverability as they cruise slowly through weed-entangled shallows, or even haul themselves through muddy pools or even over dry land for short periods.

These lobes gave rise to the tetrapod limbs common to all terrestrial vertebrates today - the Rhipidistian fish even had the same skeletal structure (humerus and radius/ulna) that all amphibians, reptiles, birds and mammals have today.

Today, the only living species of lobe-finned fish are the lungfish (Dipnoi) and the coelacanth (Latimeria), but there were more in previous eras.