Lobefins are a group of fish characterized by their fleshy, lobed fins, which are more robust than the fins of most other fish. They belong to the class Sarcopterygii and include species like coelacanths and lungfish. These fish are believed to be closely related to the ancestors of all land vertebrates, making them significant in the study of evolution. Lobefins have a unique skeletal structure that allows for more complex movement compared to ray-finned fish. Their fins are supported by bone structures similar to the limbs of terrestrial animals, which is why they are considered important in understanding the transition from water to land in vertebrate evolution.