Ancient Fish Species

noun A type of lobe-finned fish that includes the ancestors of land vertebrates

• The crossopterygian fish is known for its unique lobe fins.
• Have you ever heard of a crossopterygian fish? It's pretty cool.
• That crossopterygian fish is one funky-looking creature.
• Her ideas were like crossopterygian fossils, ancient yet still relevant.

noun Acanthodea is a taxonomic group of extinct jawed fishes that lived from the Silurian to the Permian periods.

• The acanthodea is an extinct class of fish that lived during the Paleozoic era.
• I read that the acanthodea were some of the earliest jawed fish.
• Check out those cool acanthodea fossils at the museum!
• The acanthodea were like the pioneers of the fish world, paving the way for future species.

noun a class of extinct jawed fishes that lived from the Silurian to the Permian period

• The acanthodian fish lived during the Silurian and Devonian periods.
• Have you heard of those acanthodian fish that lived millions of years ago?
• Those acanthodian fish were like the rockstars of the ancient seas.
• Her sharp wit was like the spines of an acanthodian fish, always ready to defend her arguments.

noun a type of fish belonging to the order Acipenseriformes, which includes sturgeons and paddlefish

• The acipenseroid fish is known for its long lifespan and slow growth rate.
• I saw a huge acipenseroid fish while out fishing yesterday.
• That acipenseroid is one big fish!
• Her wisdom was like that of an acipenseroid, growing slowly but steadily over time.

noun a subclass of bony fish that includes the coelacanth

• The actinistia, also known as coelacanths, are a group of ancient lobe-finned fish.
• Did you know that actinistia are considered living fossils?
• Check out those cool actinistia swimming in the aquarium!
• The actinistia are like the rockstars of the fish world, with their unique characteristics and history.