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Chimaera
Chimaeras are Chondrichthyes, cartilaginous fish in the order (biology), order Chimaeriformes (), known informally as ghost sharks, rat fish (not to be confused with rattails), spookfish, or rabbit fish; the last two names are also applied to Barreleye, Opisthoproctidae and Rabbitfish, Siganidae, respectively. At one time a "diverse and abundant" group (based on the fossil record), their closest living relatives are sharks and ray (fish), rays, though their last common ancestor with them lived nearly 400 million years ago. Living species (aside from plough-nose chimaeras) are largely confined to deep water. Anatomy Chimaeras are soft-bodied, shark-like fish with bulky heads and long, tapered tails; measured from the tail, they can grow up to in length. Like other members of the class Chondrichthyes, chimaera skeletons are entirely cartilaginous, or composed of cartilage. Males use forehead denticles to grasp a female by a fin during copulation. The Branchial arch, gill arche ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chimaeridae
The Chimaeridae, or short-nosed chimaeras, are a family (biology), family of cartilaginous fish. They resemble other Chimaeriformes, chimaeras in general form and habits, but have short, rounded snouts, without the modifications found in related families. Many species have long, tapering tails, giving them an alternative name of ratfish. Shortnose Chimaera, chimaeras have a venomous spine on their backs, which is sufficiently dangerous to injure humans. They are found in temperate and tropical marine waters worldwide. Most species are restricted to depths below , but a few, notably the spotted ratfish and rabbit fish, can locally be found at relatively shallow depths. They range from in maximum total length, depending on species. Species The species are grouped into two genera and include: Family Chimaeridae * Genus ''Chimaera (genus), Chimaera'' Carl Linnaeus, Linnaeus, 10th edition of Systema Naturae, 1758 (Eocene-Recent) ** ''Chimaera argiloba'' Peter R. Last, Last, Will ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhinochimaeridae
The Rhinochimaeridae, commonly known as long-nosed chimaeras, are a family (biology), family of cartilaginous fish. They are similar in form and habits to other chimaeras, but have an exceptionally long conical or paddle-shaped snout. The snout has numerous sensory nerve endings, and is used to find food such as small fish. The first dorsal fin includes a mildly venomous spine, used in defense. Long-nosed chimaeras are found in temperate and tropical seas worldwide, from in depth. In August 2020, a long-nosed chimaera was brought up from off the Grand Banks of Newfoundland. They range from in maximum total length, depending on species. Species The eight known species are in three genera: Family Rhinochimaeridae * Genus ''Harriotta'' George Brown Goode, Goode & Tarleton Hoffman Bean, Bean, 1895 (Late Cretaceous to present) ** ''Harriotta haeckeli'' Karrer, 1972 (smallspine spookfish) ** ''Harriotta raleighana'' Goode & Bean, 1895 (narrownose chimaera) ** Harriotta avia, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinochimaera
''Echinochimaera'' ("prickly chimaera") is an extinct genus of chimaeriform fish, known from the Lower Carboniferous Bear Gulch Limestone in Montana, United States. It is one of the earliest Chimaeriformes known. Taxonomy The genus' name derives from the Greek ''εχινό'' (''echino'') meaning spiny, and chimaera. It is assigned to the order Chimaeriformes. Species The two known ''Echinochimaera'' species lived in the Upper Mississippian (Serpukhovian). Fossils of the species were found in the Bear Gulch Limestone in Montana, United States. Both species have rounded bodies and paddle-like tails as well as large pectoral fins, two dorsal fins and a jaw fused to the braincase. The paddle-like tails indicate that ''E. meltoni'' was likely not a predator nor a fast swimmer. ''Echinochimaera meltoni'' ''E. meltoni'' was first described by Richard Lund, an Adelphi University palaeontologist, in 1977. The fossils found of ''E. meltoni'' have shown a great deal of sexual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Callorhinchidae
''Callorhinchus'', the plough-nosed chimaeras or elephantfish, are the only living genus in the family Callorhinchidae (sometimes spelled ''Callorhynchidae''). A few extinct genera only known from fossil remains are recognized. ''Callorhinchus'' spp. are similar in form and habits to other Chimaeriformes, chimaeras, but are distinguished by the presence of an elongated, flexible, fleshy snout, with a vague resemblance to a ploughshare. They are only found in the oceans of the Southern Hemisphere along the ocean bottom on muddy and sandy substrates. They filter feed, with small shellfish making up the bulk of their diet. The plough-nosed chimaera lays eggs on the ocean floor that hatch at around 8 months. They are currently not a target of conservation efforts; however, they may be susceptible to overfishing and trawling. Plough-nose chimaeras are the only extant chimaeras that still inhabit relatively shallow Neritic zone, neritic habitats, which are thought to have been the ance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protochimaera
''Protochimaera'' is an extinct genus of chimaeriform fish from the Mississippian (Early Carboniferous) of central Russia. It is the oldest known representative of the order Chimaeriformes, approximately 10 million years older than ''Echinochimaera'' (from the late Serpukhovian of Montana), and far older than the Mesozoic radiation which would lead to modern chimaeriforms, commonly known as chimaeras, rat fish, or ghost sharks. ''Protochimaera'' is known from tooth plates found at five sites southwest of the Moscow Basin. These sites correspond to the Olkhovets Formation (Tulian and Aleksinian regional stages, equivalent to the middle of the global Viséan stage) and Dashkovo Formation (Steshevian regional stage, the lower-middle part of the Serpukhovian). Like modern chimaeras (Chimaeroidei), there are three pairs of tooth plates, each developing a cutting or shearing edge. This degree of similarity suggests that ''Protochimaera'' is the sister taxon to Chimaeroidei, a propos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Callorhinchus
''Callorhinchus'', the plough-nosed chimaeras or elephantfish, are the only living genus in the family Callorhinchidae (sometimes spelled ''Callorhynchidae''). A few extinct genera only known from fossil remains are recognized. ''Callorhinchus'' spp. are similar in form and habits to other chimaeras, but are distinguished by the presence of an elongated, flexible, fleshy snout, with a vague resemblance to a ploughshare. They are only found in the oceans of the Southern Hemisphere along the ocean bottom on muddy and sandy substrates. They filter feed, with small shellfish making up the bulk of their diet. The plough-nosed chimaera lays eggs on the ocean floor that hatch at around 8 months. They are currently not a target of conservation efforts; however, they may be susceptible to overfishing and trawling. Plough-nose chimaeras are the only extant chimaeras that still inhabit relatively shallow neritic habitats, which are thought to have been the ancestral habitats for chimaerifo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chondrichthyes
Chondrichthyes (; ) is a class of jawed fish that contains the cartilaginous fish or chondrichthyans, which all have skeletons primarily composed of cartilage. They can be contrasted with the Osteichthyes or ''bony fish'', which have skeletons primarily composed of bone tissue. Chondrichthyes are aquatic vertebrates with paired fins, paired nares, placoid scales, conus arteriosus in the heart, and a lack of opercula and swim bladders. Within the infraphylum Gnathostomata, cartilaginous fishes are distinct from all other jawed vertebrates. The class is divided into two subclasses: Elasmobranchii (sharks, rays, skates and sawfish) and Holocephali ( chimaeras, sometimes called ghost sharks, which are sometimes separated into their own class). Extant chondrichthyans range in size from the finless sleeper ray to the over whale shark. Anatomy Skeleton The skeleton is cartilaginous. The notochord is gradually replaced by a vertebral column during development, e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolagus Colliei
The spotted ratfish (''Hydrolagus colliei'') is a chimaera found in the north-eastern Pacific Ocean. Often seen by divers at night in the Pacific Northwest, this cartilaginous fish gets its characteristic name from a pointed rat-like tail. The ratfish lays leathery egg case (Chondrichthyes), egg cases on the bottom of muddy or sandy areas, which are often mistaken by divers as something inanimate. While mainly a deep-water species, it occurs at shallower depths in the northern part of its range. The generic name, ''Hydrolagus'', comes from the Greek words ὕδωρ, meaning water,Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with the assistance of. Roderick McKenzie.'' Oxford: Clarendon Press. and λαγώς/λαγῶς, meaning hare, and the specific name honors Alexander Collie, who was a ship surgeon and early naturalist. The spotted ratfish is common in much of its range, not typically eaten by humans, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myriacanthidae
Myriacanthidae is an extinct family of holocephalan cartilaginous fish, closely related to living chimaeras. Fossils are known from the latest Triassic (Rhaetian) and Early Jurassic of Europe. Description Like other cartilaginous fish, most myriacanthids are only known from their teeth (and in a few cases their fin spines), though a handful of species are known from partial skeletons which preserve the cartilage. Members of Myriacanthidae generally have elongate rostra with long frontal claspers. On the lower jaw, there is a dermal plate, and parts of the head are covered in dermal plates in some genera. There are three pairs of tooth plates in the upper jaw, of which the pair furthest back in the mouth are the largest. Like other members of Myriacanthoidei, they have dorsal fins supported by fin spines which are ornamented with tubercles. The synarcual is articulated with a basal cartilage. The notochord is surrounded by calcified rings (or alternatively paired half rings). T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chimaeropsis
''Chimaeropsis'' is an extinct genus of cartilaginous fish related to modern chimaeras, known from the Jurassic of Europe. Taxonomy The genus and species ''Chimaeropsis paradoxa'' was originally erected in 1887 by Zittel, based on a "'fairly well-preserved skeleton", which was around long found in the Upper Jurassic Plattenkalk limestones of Germany. This specimen, while partially described by both Zittel and Riess in 1887 and later again by Reiss in 1895, was never properly figured and is assumed to have been destroyed by bombings during World War II. As the only other known specimens of the species were fragmentary, this left much of the anatomy of the species enigmatic for most of the 20th century and early 21st century. In 1965, Patterson placed it as the only known member of its family, the Chimaeropsidae, and closely related to the family Myriacanthidae within the clade Myriacanthoidei. In modern taxonomic schemes, Myriacanthoidei has been placed as closely related to mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squaloraja
''Squaloraja'' (Latin for "shark- skate") is an extinct genus of ray-like marine chimaeriform fish from the Early Jurassic of Europe. Taxonomy It contains a single named species known from the Sinemurian-aged Blue Lias of Lyme Regis, England: ''S. polyspondyla'' Agassiz, 1836, with complete specimens representing both males and females. A second species from the same locality, ''S. tenuispina'' Woodward, 1886 (known from an isolated horn of a male), is now considered conspecific with ''S. polyspondyla''. In addition, the complete specimen of the female of an indeterminate species is known from the Sinemurian-aged Moltrasio Formation of Osteno, Italy, and indeterminate teeth are known from the earlier Hettangian of Belgium. Divergence estimates suggest that ''Squaloraja'' was a relict taxon and the last surviving member of a chimaera lineage that had diverged from the Chimaeroidei by the late Mississippian stage of the Carboniferous period, as stem-chimaeroids already app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
