Search results
Results from the WOW.Com Content Network
Hagfish, of the class Myxini / m ɪ k ˈ s aɪ n aɪ / (also known as Hyperotreti) and order Myxiniformes / m ɪ k ˈ s ɪ n ɪ f ɔːr m iː z /, are eel-shaped jawless fish (occasionally called slime eels). Hagfish are the only known living animals that have a skull but no vertebral column, although they do have rudimentary vertebrae. [3]
Cyclostomi, often referred to as Cyclostomata / s ɪ k l oʊ ˈ s t ɒ m ə t ə /, is a group of vertebrates that comprises the living jawless fishes: the lampreys and hagfishes.Both groups have jawless mouths with horny epidermal structures that function as teeth called ceratodontes, and branchial arches that are internally positioned instead of external as in the related jawed fishes. [1]
The head, as in all agnathans, does not have jaws, and the sucker-like mouth is always open, [5] with 8 barbels around it. There are no visible eyes. [4] Hagfish also only have one nostril, which is located above the mouth. [6] Pacific hagfish heads. Starting about one quarter of their body length from the front are 10–14 gill pores. [4]
The Atlantic hagfish may grow up to .75 metres (2 + 1 ⁄ 2 ft) long, with no eyes and no jaws; its star-shaped mouth is surrounded by 6 mouth barbels. [3] Their eyes also lack a lens and pigment (features found in the eyes of all other living vertebrates. [4] There is a single gill slit on each side of the eel-like body. [3]
As with all other hagfish, the New Zealand hagfish has a skull but no jaw or true vertebral column, it instead has a skeleton made up of cartilage. [5] The rounded mouth of the hagfish is surrounded by 6 barbels, above that is their singular nasal passage and just inside the mouth is a dental plate with a row of posterior and anterior ...
A craniate is a member of the Craniata (sometimes called the Craniota), a proposed clade of chordate animals with a skull of hard bone or cartilage.Living representatives are the Myxini (hagfishes), Hyperoartia (including lampreys), and the much more numerous Gnathostomata (jawed vertebrates).
Agnatha (/ ˈ æ ɡ n ə θ ə, æ ɡ ˈ n eɪ θ ə /; [3] from Ancient Greek ἀ-(a-) 'without' and γνάθος (gnáthos) 'jaws') is a paraphyletic infraphylum [4] of non-gnathostome vertebrates, or jawless fish, in the phylum Chordata, subphylum Vertebrata, consisting of both living (cyclostomes) and extinct (conodonts, anaspids, and ostracoderms, among others).
The white-headed hagfish may grow up to 57 centimetres (1.87 ft) long. [5] It is a seven-gilled hagfish; it can be distinguished from related species by its large number of tooth cusps: between 44 and 51. [9] The Irish M. ios population is distinguished from the southern variety by its white head and whitish middorsal or midventral line. [10]