Which of the following belongs to Gnathostomata?

Which of the following belongs to Gnathostomata?

The group, Gnathostomata, is traditionally a infraphylum, broken into three top-level groupings: Chondrichthyes, or the cartilaginous fish; Placodermi, an extinct clade of armored fish; and Teleostomi, which includes the familiar classes of bony fish, birds, mammals, reptiles, and amphibians.

What is Agnatha and Gnathostomata?

The key difference between Agnathans and Gnathostomata is that Agnathans are organisms that do not possess a jaw while Gnathostomata are organisms with jaws. Agnathans are jawless fish. Gnathostomata are fish that have jaws. Both agnathans and Gnathostomata are very important in determining evolutionary relationships.

Where did the Gnathostome jaws come from?

The jaw in gnathostomes (jawed vertebrates) is one of the earliest innovations in the evolution of vertebrates and is derived from the mandibular arch (MA).

When did Gnathostomata evolve?

approximately 370 million years ago
Chondrichthyes: Cartilaginous Fishes This clade arose approximately 370 million years ago in the early or middle Devonian.

What is a superclass Gnathostomata?

1. A superclass of jawed vertebrates that includes the fishes, Amphibia, Reptilia, Aves, and Mammalia. Recently it has been proposed that Gnathostomata should comprise the Elasmobranchii (sharks, rays, etc.) and the Teleostomi (i.e. Osteichthyes and Sarcopterygii).

Is Gnathostomata a phylum?

ChordateGnathostomata / Phylum

Is Gnathostomata a superclass?

1. A superclass of jawed vertebrates that includes the fishes, Amphibia, Reptilia, Aves, and Mammalia.

Are humans Gnathostomata?

The group gnathostomes, meaning “jaw-mouths,” includes tens of thousands of living vertebrate species, ranging from fish and sharks to birds, reptiles, mammals and humans.

What is Gnathostomata in zoology?

A superclass of the subphylum Vertebrata consisting of animals that possess jaws. The superclass Gnathostomata comprises the jawed vertebrates (subphylum Vertebrata, phylum Chordata). In other words, gnathostomes are animals with jaws, involving a vertical biting that developed from modified gill arches.

What is the meaning of Gnathostomata?

Definition of Gnathostomata. : a superclass or other division of Vertebrata comprising those with jaws — compare agnatha.

Is Entelognathus the ancestor of gnathostomes?

The fossil findings of primitive bony fishes such as Guiyu oneiros and Psarolepis, which lived contemporaneously with Entelognathus and had pelvic girdles more in common with placoderms than with other bony fish, show that it was a relative rather than a direct ancestor of the extant gnathostomes.

When did the first gnathostome fossil appear?

Undeniably unambiguous gnathostome fossils, mostly of primitive acanthodians, begin appearing by the early Silurian, and become abundant by the start of the Devonian .

What is the difference between Gnathostomata and Osteostraci?

Gnathostomata. The Osteostraci are generally considered the sister taxon of Gnathostomata. It is believed that the jaws evolved from anterior gill support arches that had acquired a new role, being modified to pump water over the gills by opening and closing the mouth more effectively – the buccal pump mechanism.