30-492: Semotilus is the genus of creek chubs , ray-finned fish in the family Cyprinidae . The term "creek chub" is sometimes used for individual species, particularly the common creek chub, S. atromaculatus . The creek chub species of minnows can grow from 6 to 10 inches (15 to 25 cm). They can be found in the United States and Canada in any small stream or creek. They hide under small rocks for protection. They have
60-459: A free-swimming larval stage. However other patterns of ontogeny exist, with one of the commonest being sequential hermaphroditism . In most cases this involves protogyny , fish starting life as females and converting to males at some stage, triggered by some internal or external factor. Protandry , where a fish converts from male to female, is much less common than protogyny. Most families use external rather than internal fertilization . Of
90-416: A remnant structure: in gars, the spiracles do not even open to the outside; the skeleton is lightly ossified : a thin layer of bone covers a mostly cartilaginous skeleton in the bowfins. In gars, the tail is still heterocercal but less so than in the chondrosteans. Bowfins have many-rayed dorsal fins and can breathe air like the bichirs . In the holosteans a primary pulmonoid (respiratory) swim bladder
120-645: A small black spot on the dorsal fin for easy identification. Members of genus Semotilus readily take all sorts of natural and artificial bait. They can grow quite large, Fallfish and Creek Chub especially, putting up a good fight on ultralight tackle. This Leuciscidae article is a stub . You can help Misplaced Pages by expanding it . Ray-finned fish Actinopterygii ( / ˌ æ k t ɪ n ɒ p t ə ˈ r ɪ dʒ i aɪ / ; from actino- 'having rays' and Ancient Greek πτέρυξ (ptérux) 'wing, fins'), members of which are known as ray-finned fish or actinopterygians ,
150-742: A trait still present in Holostei ( bowfins and gars ). In some fish like the arapaima , the swim bladder has been modified for breathing air again, and in other lineages it have been completely lost. The teleosts have urinary and reproductive tracts that are fully separated, while the Chondrostei have common urogenital ducts, and partially connected ducts are found in Cladistia and Holostei. Ray-finned fishes have many different types of scales ; but all teleosts have leptoid scales . The outer part of these scales fan out with bony ridges, while
180-587: Is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of skin supported by radially extended thin bony spines called lepidotrichia , as opposed to the bulkier, fleshy lobed fins of the sister class Sarcopterygii (lobe-finned fish). Resembling folding fans , the actinopterygian fins can easily change shape and wetted area , providing superior thrust-to-weight ratios per movement compared to sarcopterygian and chondrichthyian fins. The fin rays attach directly to
210-546: Is a group of ray-finned bony fish . It is divided into two major clades, the Halecomorphi , represented by the single living genus, Amia with two species, the bowfins ( Amia calva and Amia ocellicauda ), as well as the Ginglymodi , the sole living representatives being the gars (Lepisosteidae), represented by seven living species in two genera ( Atractosteus , Lepisosteus ). The earliest members of
240-545: Is divided into the infraclasses Holostei and Teleostei . During the Mesozoic ( Triassic , Jurassic , Cretaceous ) and Cenozoic the teleosts in particular diversified widely. As a result, 96% of living fish species are teleosts (40% of all fish species belong to the teleost subgroup Acanthomorpha ), while all other groups of actinopterygians represent depauperate lineages. The classification of ray-finned fishes can be summarized as follows: The cladogram below shows
270-432: Is relatively rare and is found in about 6% of living teleost species; male care is far more common than female care. Male territoriality "preadapts" a species for evolving male parental care. There are a few examples of fish that self-fertilise. The mangrove rivulus is an amphibious, simultaneous hermaphrodite, producing both eggs and spawn and having internal fertilisation. This mode of reproduction may be related to
300-431: Is still present, a trait that was independently lost in both chondrostei and teleostei, the only other two lineages of fish with a swim bladder (in some teleosts the swim bladder have since evolved to become secondarily respiratory again). The gars have thick ganoid scales typical of sturgeons whereas the bowfin has thin bony scales like the teleosts. The gars are therefore in this regard considered more primitive than
330-506: The Cyprinidae (in goldfish and common carp as recently as 14 million years ago). Ray-finned fish vary in size and shape, in their feeding specializations, and in the number and arrangement of their ray-fins. In nearly all ray-finned fish, the sexes are separate, and in most species the females spawn eggs that are fertilized externally, typically with the male inseminating the eggs after they are laid. Development then proceeds with
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#1732780863601360-592: The deep sea to subterranean waters to the highest mountain streams . Extant species can range in size from Paedocypris , at 8 mm (0.3 in); to the massive ocean sunfish , at 2,300 kg (5,070 lb); and to the giant oarfish , at 11 m (36 ft). The largest ever known ray-finned fish, the extinct Leedsichthys from the Jurassic , has been estimated to have grown to 16.5 m (54 ft). Ray-finned fishes occur in many variant forms. The main features of typical ray-finned fish are shown in
390-488: The oviparous teleosts, most (79%) do not provide parental care. Viviparity , ovoviviparity , or some form of parental care for eggs, whether by the male, the female, or both parents is seen in a significant fraction (21%) of the 422 teleost families; no care is likely the ancestral condition. The oldest case of viviparity in ray-finned fish is found in Middle Triassic species of † Saurichthys . Viviparity
420-563: The sister group of Teleostei , the major group of living neopterygians, rendering the Holostei paraphyletic . Teleostei [REDACTED] Halecomorphi [REDACTED] Ginglymodi [REDACTED] The Holostei hypothesis, where the gars and bowfin form the clade Holostei as the sister group to Teleostei, is better supported than the Halecostomi hypothesis, rendering the latter paraphyletic. It proposes Halecomorphi as
450-663: The sister lineage of all other actinopterygians, the Acipenseriformes (sturgeons and paddlefishes) are the sister lineage of Neopterygii, and Holostei (bowfin and gars) are the sister lineage of teleosts. The Elopomorpha ( eels and tarpons ) appear to be the most basal teleosts. The earliest known fossil actinopterygian is Andreolepis hedei , dating back 420 million years ( Late Silurian ), remains of which have been found in Russia , Sweden , and Estonia . Crown group actinopterygians most likely originated near
480-938: The Devonian-Carboniferous boundary. The earliest fossil relatives of modern teleosts are from the Triassic period ( Prohalecites , Pholidophorus ), although it is suspected that teleosts originated already during the Paleozoic Era . The listing below is a summary of all extinct (indicated by a dagger , †) and living groups of Actinopterygii with their respective taxonomic rank . The taxonomy follows Phylogenetic Classification of Bony Fishes with notes when this differs from Nelson, ITIS and FishBase and extinct groups from Van der Laan 2016 and Xu 2021. [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] Holostei Holostei
510-402: The adjacent diagram. The swim bladder is a more derived structure and used for buoyancy . Except from the bichirs , which just like the lungs of lobe-finned fish have retained the ancestral condition of ventral budding from the foregut , the swim bladder in ray-finned fishes derives from a dorsal bud above the foregut. In early forms the swim bladder could still be used for breathing,
540-463: The bichirs and holosteans (bowfin and gars) in having gone through a whole-genome duplication ( paleopolyploidy ). The WGD is estimated to have happened about 320 million years ago in the teleosts, which on average has retained about 17% of the gene duplicates, and around 180 (124–225) million years ago in the chondrosteans. It has since happened again in some teleost lineages, like Salmonidae (80–100 million years ago) and several times independently within
570-464: The bowfin. The name Holostei derives from the Greek words holos , meaning whole, and osteon , meaning bone: a reference to their bony skeletons. The evolutionary relationships of gars, bowfin and teleosts were a matter of debate. There are two competing hypotheses on the systematics of neopterygians : The Halecostomi hypothesis proposes Halecomorphi ( bowfin and its fossil relatives) as
600-573: The clade, which are putative " semionotiforms " such as Acentrophorus and Archaeolepidotus , are known from the Middle to Late Permian and are among the earliest known neopterygians . Holostei was thought to be regarded as paraphyletic . However, a recent study provided evidence that the Holostei are the closest living relatives of the Teleostei , both within the Neopterygii . This
630-706: The different actinopterygian clades (in millions of years , mya) are from Near et al., 2012. Jaw-less fishes ( hagfish , lampreys ) [REDACTED] Cartilaginous fishes ( sharks , rays , ratfish ) [REDACTED] Coelacanths [REDACTED] Lungfish [REDACTED] Amphibians [REDACTED] Mammals [REDACTED] Sauropsids ( reptiles , birds ) [REDACTED] Polypteriformes ( bichirs , reedfishes ) [REDACTED] Acipenseriformes ( sturgeons , paddlefishes ) [REDACTED] Teleostei [REDACTED] Amiiformes ( bowfins ) [REDACTED] Lepisosteiformes ( gars ) [REDACTED] The polypterids (bichirs and reedfish) are
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#1732780863601660-432: The fish's habit of spending long periods out of water in the mangrove forests it inhabits. Males are occasionally produced at temperatures below 19 °C (66 °F) and can fertilise eggs that are then spawned by the female. This maintains genetic variability in a species that is otherwise highly inbred. Actinopterygii is divided into the subclasses Cladistia , Chondrostei and Neopterygii . The Neopterygii , in turn,
690-437: The fishes. The gars have elongated jaws with fanlike teeth, only 3 branchiostegal rays, and a small dorsal fin. Meanwhile the bowfins have a terminal mouth, 10–13 flattened branchiostegal rays, and a long dorsal fin. The cladogram shows the relationships of holosteans to other living groups of bony fish (Osteichthyes), the great majority of which are teleosts , and to the terrestrial vertebrates (tetrapods) that evolved from
720-409: The gars are more primitive than those of the bowfin. Holosteans share with other non-teleost ray-finned fish a mixture of characteristics of teleosts and sharks . In comparison with the other group of non-teleost ray-finned fish, the chondrosteans , the holosteans are closer to the teleosts and further from sharks: the pair of spiracles found in sharks and chondrosteans is reduced in holosteans to
750-438: The inner part is crossed with fibrous connective tissue. Leptoid scales are thinner and more transparent than other types of scales, and lack the hardened enamel - or dentine -like layers found in the scales of many other fish. Unlike ganoid scales , which are found in non-teleost actinopterygians, new scales are added in concentric layers as the fish grows. Teleosts and chondrosteans (sturgeons and paddlefish) also differ from
780-466: The main clades of living actinopterygians and their evolutionary relationships to other extant groups of fishes and the four-limbed vertebrates ( tetrapods ). The latter include mostly terrestrial species but also groups that became secondarily aquatic (e.g. whales and dolphins ). Tetrapods evolved from a group of bony fish during the Devonian period . Approximate divergence dates for
810-524: The orders Parasemionotiformes , Panxianichthyiformes , Ionoscopiformes , and Amiiformes . In addition to many extinct species , Amiiformes includes only 1 extant species that is commonly referred to as the bowfin. Parasemionotiformes, Panxianichthyiformes, and Ionoscopiformes have no living members. Gars and bowfins are found in North America and in freshwater ecosystems. The differences in each can be spotted very easily from just looking at
840-494: The proximal or basal skeletal elements, the radials, which represent the articulation between these fins and the internal skeleton (e.g., pelvic and pectoral girdles). The vast majority of actinopterygians are teleosts . By species count, they dominate the subphylum Vertebrata , and constitute nearly 99% of the over 30,000 extant species of fish . They are the most abundant nektonic aquatic animals and are ubiquitous throughout freshwater and marine environments from
870-620: The sister group of Ginglymodi , the group which includes living gars ( Lepisosteiformes ) and their fossil relatives. It is estimated that the last common ancestor of gars and bowfin lived at least 250 million years ago. Teleostei [REDACTED] Halecomorphi [REDACTED] Ginglymodi [REDACTED] Ginglymodi comprises three orders : Lepisosteiformes , Semionotiformes and Kyphosichthyiformes . Lepisosteiformes includes 1 family , 2 genera , and 7 species that are commonly referred to as gars. Semionotiformes and Kyphosichthyiformes are extinct orders. Halecomorphi contains
900-489: Was found from the morphology of the Holostei, for example presence of a paired vomer . Holosteans are closer to teleosts than are the chondrosteans , the other group intermediate between teleosts and cartilaginous fish, which are regarded as (at the nearest ) a sister group to the Neopterygii. The spiracles of holosteans are reduced to vestigial remnants and the bones are lightly ossified. The thick ganoid scales of
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