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The same anatomical structure can serve different functions in the lamprey depending on whether or not it is carnivorous. The mouth and suction capabilities of the lamprey not only allow it to cling to a fish as a parasite, [41] but provide it with limited climbing ability so that it can travel upstream and up ramps or rocks to breed.
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]
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 Pacific lamprey (Entosphenus tridentatus) is an anadromous parasitic lamprey from the Pacific Coast of North America and Asia in an area called the Pacific Rim. [4] It is a member of the Petromyzontidae family. The Pacific lamprey is also known as the three-tooth lamprey and tridentate lamprey. Ammocoetes held by biologist in the Carmel River
The sea lamprey (Petromyzon marinus) is a parasitic lamprey native to the Northern Hemisphere. It is sometimes referred to as the "vampire fish". It is sometimes referred to as the "vampire fish". In its original habitats, the sea lamprey coevolved with its hosts, and those hosts evolved a measure of resistance to the sea lampreys.
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).
The vertebrate jaw is generally thought to be the modification of the mandibular arch (1st pharyngeal arch). Since the trabecular cartilages appear anterior to the mandibular arch, if the trabecular cartilages are serial homologues of the pharyngeal arches, ancestral vertebrates should possess more than one pharyngeal arch (so-called ...
The eyes were rather small and placed on the top of the head. There was no jaw proper. The mouth opening was surrounded by small plates, making the lips flexible, but without any ability to bite. [3] No internal skeleton is known, outside of the head shield. If they had a vertebral column at all, it would have been cartilage rather than bone.