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Lampreys
Lampreys (sometimes inaccurately called lamprey eels) are a group of Agnatha, jawless fish comprising the order (biology), order Petromyzontiformes , sole order in the Class (biology), class Petromyzontida. The adult lamprey is characterized by a toothed, funnel-like sucking mouth. The common name "lamprey" is probably derived from Latin , which may mean "stone licker" ( "to lick" + "stone"), though the etymology is uncertain. "Lamprey" is sometimes seen for the plural form. About 38 extant species of lampreys are known, with around seven known extinct species. They are classified in three families—two small families in the Southern Hemisphere (Geotriidae, Mordaciidae) and one large family in the Northern Hemisphere (Petromyzontidae). Genetic evidence suggests that lampreys are more closely related to hagfish, the only other living group of jawless fish, than they are to jawed vertebrates, forming the superclass Cyclostomi. The oldest fossils of stem-group lampreys are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamprey Larva X Sect Pharynx Labelled
Lampreys (sometimes inaccurately called lamprey eels) are a group of jawless fish comprising the order Petromyzontiformes , sole order in the class Petromyzontida. The adult lamprey is characterized by a toothed, funnel-like sucking mouth. The common name "lamprey" is probably derived from Latin , which may mean "stone licker" ( "to lick" + "stone"), though the etymology is uncertain. "Lamprey" is sometimes seen for the plural form. About 38 extant species of lampreys are known, with around seven known extinct species. They are classified in three families—two small families in the Southern Hemisphere ( Geotriidae, Mordaciidae) and one large family in the Northern Hemisphere ( Petromyzontidae). Genetic evidence suggests that lampreys are more closely related to hagfish, the only other living group of jawless fish, than they are to jawed vertebrates, forming the superclass Cyclostomi. The oldest fossils of stem-group lampreys are from the latest Devonian, around 360 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agnatha
Agnatha (; ) or jawless fish is a paraphyletic infraphylum of animals in the subphylum Vertebrata of the phylum Chordata, characterized by the lack of jaws. The group consists of both extant taxon, living (Cyclostomi, cyclostomes such as hagfishes and lampreys) and Extinction, extinct clades (e.g. conodonts and Cephalaspidomorphi, cephalaspidomorphs, among others). They are sister taxon, sister to vertebrates with jaws known as gnathostomes, who evolution, evolved from jawless ancestors during the early Silurian by developing folding joint, articulations in the first pairs of gill arches. Sequencing, Molecular data, both from rRNA and from mtDNA as well as Embryology, embryological data, strongly supports the hypothesis that both groups of living agnathans, hagfishes and lampreys, are more closely related to each other than to Gnathostomata, jawed fish, forming the Class (biology), superclass Cyclostomi. The oldest fossil agnathans appeared in the Cambrian. Living jawless fish c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petromyzon Marinus
The sea lamprey (''Petromyzon marinus'') is a parasitic lamprey native to the Northern Hemisphere. It is sometimes referred to as the "vampire fish". It was likely introduced to the Great Lakes region through the Erie Canal in 1825 and the Welland Canal in 1919 where it has attacked native fish such as lake trout, lake whitefish, chub, and lake herring. Sea lampreys are considered a pest in the Great Lakes region as each individual has the potential of killing 40 pounds of fish through its 12–18 month feeding period. Description The sea lamprey has an eel-like body without paired fins. Its mouth is jawless, round and sucker-like, and as wide or wider than the head; sharp teeth are arranged in many concentric circular rows around a sharp, rasp-like tongue. There are seven branchial or gill-like openings behind the eye. Sea lampreys are olive or brown-yellow on the dorsal and lateral part of the body, with some black marblings, with lighter coloration on the belly. Within ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Priscomyzon
''Priscomyzon riniensis'' is an extinct lamprey that lived some 360 million years ago during the Famennian (Late Devonian) in a marine or estuarine environment in South Africa. This small agnathan is anatomically similar to the Mazon Creek lampreys, but is some 35 million years older. Its key developments included the first known large oral disc, circumoral teeth and a branchial basket. Context Though common and diverse during the Silurian and Devonian, jawless fish are today represented only by lampreys and hagfish, both groups being quite specialized. Lampreys have seven gill pouches (whereas jawed fish have only five), no paired fins, and a rudimentary skeleton of cartilage. They also have a sucker disc of cartilage surrounded by a soft lip and a central small mouth set about with simple hooked teeth. They attach to the bodies of other vertebrates by suction, securing their grip with the hooked teeth, after which a rasped tongue scrapes a hole providing access to the host' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caeruleum (lamprey)
''Caeruleum'' is an extinct genus of lamprey from the Lower Cretaceous Jiufotang Formation of China. The genus contains two species, ''C. miraculum'' and ''C. gracilis'', known from various specimens including complete and partial bodies. Discovery and naming The first described ''Caeruleum'' fossil material was discovered in sediments of the Jiufotang Formation near Naizi (or Naitou) Mountain in Weichang County of Chengde City, Hebei Province, China. Various lamprey specimens were found in this formation. In 2023, Weijia Huang described ''Caeruleum miraculum'' as a new genus and species of lamprey based on several fossil remains. The holotype specimen, BMM 3770, consists of a complete animal preserved on a slab and counterslab. Several additional specimens of various levels of completion were also assigned to ''Caeruleum'' as paratypes. These include BMM 3771 (an incomplete specimen with a complete tail), BMM 3772 (the posterior end of an animal with a mutilated tail), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardistiella
''Hardistiella montanensis'' is an extinct species of lamprey, found, dating from the Carboniferous period, at the Bear Gulch Limestone site in the U.S. state of Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an .... P. Janvier and R. Lund. 1983. Hardistiella montanensis n. gen. et sp. (Petromyzontida) from the Lower Carboniferous of Montana, with remarks on the affinities of the lampreys. ''Journal of Vertebrate Paleontology'' 2(4):407-413 References {{Taxonbar, from=Q60431263, from2=Q60431365 † Fossils of Montana Fossil taxa described in 1983 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hagfish
Hagfish, of the Class (biology), class Myxini (also known as Hyperotreti) and Order (biology), order Myxiniformes , are eel-shaped Agnatha, jawless fish (occasionally called slime eels). Hagfish are the only known living Animal, animals that have a skull but no vertebral column, although they do have rudimentary vertebrae. Hagfish are marine animal, marine predators and scavengers that can defend themselves against other larger predators by releasing copious amounts of slime coat, slime from mucous glands in their skin. Although their exact relationship to the only other extant taxon, living group of Agnatha, jawless fish, the lampreys, was long the subject of controversy, genetic evidence suggests that hagfish and lampreys are more closely related to each other than to jawed vertebrates, thus forming the superclass Cyclostomi. The oldest-known stem group hagfish are known from the Pennsylvanian (geology), Late Carboniferous, around Moscovian (Carboniferous), 310 million years ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mayomyzon
''Mayomyzon pieckoensis'' is an extinct species of lamprey that lived during the Late Carboniferous period, about 300 million years ago. It is the only known species of the genus ''Mayomyzon'', which belongs to the family Mayomyzontidae. It is known from the Mazon Creek fossil beds located in present-day Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its .... Description The fossil of ''M. pieckoensis'' is preserved as a carbon film in a concretion, which shows the outline of its body and some internal structures. The specimen is about 10 cm long and has a circular mouth with teeth, a single nostril, seven pairs of gill openings, and a dorsal fin that extends to the tail. The fossil also reveals that ''M. pieckoensis'' had pigmented eyes, which are rare among fossil verte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesomyzon
''Mesomyzon mengae'' is an extinct lamprey from freshwater strata of the Early Cretaceous-aged Yixian Formation, in China. The animal's exquisitely preserved fossils show a creature very similar to modern-day lampreys, having a well-developed sucking oral disk, a branchial basket, at least seven pairs of gill pouches and corresponding gill arches, impressions of gill filaments, and at least 80 myomeres of its musculature. It had the same three phase life cycle found in modern lampreys. A phylogenetic analysis conducted in 2018 shows that ''Mesomyzon'' is the fossil lamprey most closely related to modern taxa, though it is not closely related to any modern group. On the other hand, Brownstein & Near (2022) found it to be a member of the lamprey crown group, most closely related to Petromyzontidae. However, a 2023 study found it again to be a derived stem Stem or STEM most commonly refers to: * Plant stem, a structural axis of a vascular plant * Stem group * Science, technolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pipiscius
''Pipiscius'' is an extinct genus of lamprey that lived about 300 million years ago, during the Middle Pennsylvanian Epoch of the Carboniferous Period. The genus contains a single species, ''P. zangerli'', known from the Mazon Creek fossil beds located in present-day Illinois. It has a distinctive crown-like mouth comprising a ring of radially arranged teeth. However, some specimens assigned to the coeval lamprey ''Mayomyzon'', also found in the Mazon Creek beds, also have similar mouthparts. Since ''Pipiscius'' does not have many any other defining features, it has been suggested that the two genera are synonymous A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ..., with the name ''Mayomyzon'' having priority. Fossil collectors have nicknamed ''Pipiscius'' the “Push me-Pull ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yanliaomyzon
''Yanliaomyzon'' is an extinct genus of predatory lampreys that lived approximately 163 million years ago during the Middle Jurassic. It is found in the Yanliao Biota, including both the Daohugou Beds and the Tiaojishan Formation in Liaoning province, northern China. The genus has two species: ''Yanliaomyzon occisor'' and ''Yanliaomyzon ingensdentes''. These species are significant for being the earliest lampreys to closely resemble modern species. Description The species ''Y. occisor'' has a body length of , which would make it the largest extinct fossil lamprey discovered. Both members of this genus resemble the modern pouched lamprey (''Geotria australis''). ''Yanliaomyzon'' bears a toothed oral disc that is much more similar to those of modern lampreys than those of Paleozoic lampreys. The two species are distinguished by differences in the anatomy of the toothed oral disc, as well as that the tail occupies around 40% of the body length in ''Yanliaomyzon ingensdentes'' but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
