Agnatha (/ ˈæɡnəθə, æɡˈneɪθə /; [3] from Ancient Greek ἀ- (a-) 'without' and γνάθος (gnáthos) 'jaws') or jawless fish is a paraphyletic infraphylum [4] of animals in the subphylum Vertebrata …

Dec 15, 2025 · Agnathan - Evolution, Classification, Jawless: Superclass Agnatha have fossils dating from the Ordovician Period, and are distinguishable from the other craniates by their …

Sep 7, 2025 · Now, what is a jawless fish (Agnatha)? Agnatha species, or jawless fish, are said to be the earliest vertebrates ever recorded, believed to have been present during the Paleozoic …

Nov 25, 2025 · Agnatha is the superclass of vertebrates in which true jaws are absent. It is the group that represent the most primitive and earliest craniates, and in this group the mouth …

Dec 15, 2025 · Jawless fish, belonging to the infraphylum Agnatha, are unique among vertebrates due to their lack of jaws. They possess long, cylindrical bodies devoid of paired fins and scales …

Most agnathans are now extinct, but two branches exist today: hagfishes (not true vertebrates) and lampreys (true vertebrates). The earliest jawless fishes were the ostracoderms, which had …

In the past, hagfishes and lampreys were sometimes recognized as separate clades within the Agnatha, primarily because lampreys were regarded as true vertebrates, whereas hagfishes …

Mar 22, 2025 · The term “Agnatha” is derived from Greek, where “ a ” means without, and “ gnathos ” means jaw. This Superclass of Vertebrae lacks a true jaw and paired fins, …

Agnatha (Greek, "no jaws"), often considered a superclass within the subphylum Vertebrata, comprises the jawless fish —the oldest known vertebrates. The two extant groups of jawless …

Agnatha refers to a superclass of jawless fish, which includes species such as lampreys and hagfish. These ancient marine organisms are characterized by their lack of jaws, paired fins, …