The Middle Jurassic is the second epoch of the Jurassic Period . It lasted from about 174.1 to 161.5 million years ago . Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations containing land animal fossils include the Forest Marble Formation in England, the Kilmaluag Formation in Scotland , the Calcaire de Caen of France , the Daohugou Beds in China, the Itat Formation in Russia , the Tiouraren Formation of Niger , and the Isalo III Formation of western Madagascar .
19-476: See text Osteoglossidae is a family of large-sized freshwater fish, which includes the arowanas . They are commonly known as bonytongues . The family has been regarded as containing two extant subfamilies Arapaiminae and Osteoglossinae , with a total of five living genera, but these are regarded as valid families in Eschmeyer's Catalog of Fishes The extinct Phareodontinae are known from worldwide during
38-792: Is Cretophareodus from the middle Campanian of the Dinosaur Park Formation , Canada, but a potentially older genus may be Chanopsis from the Albian of the Democratic Republic of the Congo . Although currently restricted to freshwater habitats in the tropics, the group was much more widespread during the Cretaceous and Paleogene , with genera known from North America and Europe , including marine taxa such as Brychaetus . An indeterminate marine osteoglossid
57-629: Is an endangered species and banned in the United States. It is a status symbol among wealthy Asian men. An albino arowana sold for a record price of $ 300,000 in 2009. Most pet arowana are farmed behind high-security fences. Arowanas are solitary fish and only allow company while young; adults may show dominance and aggression. Some compatible species often partnered with this fish are clown knifefish , pacu , oscars , jaguar cichlids , green terrors , gar , tinfoil barb , Siamese tigerfish , and any other somewhat aggressive fish that cannot fit in
76-457: Is covered by large, heavy scales, with a mosaic pattern of canals. The dorsal and anal fins have soft rays and are long based, while the pectoral and ventral fins are small. The name "bonytongues" is derived from a toothed bone on the floor of the mouth, the "tongue", equipped with teeth that bite against teeth on the roof of the mouth. The arowana is a facultative air breather and can obtain oxygen from air by sucking it into its swim bladder , which
95-636: Is estimated that the total annual revenue of the Asian arowana sector was over US$ 200 million globally since 2012. The name comes from the Tupí language arua'ná , aruanã , or arauaná . [REDACTED] [REDACTED] Middle Jurassic During the Middle Jurassic Epoch, Pangaea began to separate into Laurasia and Gondwana , and the Atlantic Ocean formed. Eastern Laurasia
114-524: Is known to have inhabited the seas around Greenland in the Early Paleocene , and they later become diverse in marine habitats during the Eocene, with many genera known from Europe. Modern osteoglossids of both subfamilies have a roughly Gondwanan distribution confined to freshwater habitats. For this reason, it was formerly assumed that extant osteoglossids descend from an ancestor that inhabited
133-700: Is lined with capillaries like lung tissue . Within Osteoglossinae, the South America Osteoglossum arowanas diverged from the Asian and Australian Scleropages arowanas about 170 Mya, during the Middle Jurassic . The Osteoglossidae are the only exclusively freshwater fish family found on both sides of the Wallace Line . This may be explained by the theory that Asian arowanas ( S. formosus ) diverged from
152-682: The Late Cretaceous and Paleogene ; they are generally considered to be crown group osteoglossids that are more closely related to one of the extant osteoglossid subfamilies than the other, though their exact position varies. Osteoglossids are basal teleosts that originated during the Cretaceous , and are placed in the actinopterygian order Osteoglossiformes . The traditionally defined wider family includes several extant species from South America, one from Africa , two from Asia, and two from Australia . The earliest known osteoglossid
171-632: The Australian Scleropages , S. jardinii and S. leichardti , about 140 Mya, making it likely that Asian arowanas were carried to Asia on the Indian subcontinent . At least five extinct genera, known only from fossils, are classified as osteoglossids; these date back at least as far as the Late Cretaceous . Other fossils from as far back as the Late Jurassic or Early Cretaceous are widely considered to belong to
190-528: The Middle Jurassic, (including cetiosaurs , brachiosaurs , megalosaurs and primitive ornithopods ). Descendants of the therapsids , the cynodonts , were still flourishing along with the dinosaurs. These included the tritylodonts and mammals. Mammals remained quite small, but were diverse and numerous in faunas from around the world. Tritylodonts were larger, and also had an almost global distribution. The first crown-group mammals appeared in
209-550: The arowana superorder Osteoglossomorpha . Osteoglossomorph fossils have been found on all continents except Antarctica. These fossil genera include Brychaetus , Joffrichthys , and Phareodus . Osteoglossids are carnivorous , often being specialized surface feeders. They are excellent jumpers; Osteoglossum species have been seen leaping more than 6 feet (1.8 m) from the water surface to pick off insects and birds from overhanging branches in South America, hence
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#1732779838327228-448: The arowana's mouth. These fish are best kept with live or frozen feed and they easily outgrow the tank within eight to ten months. An aquarium with the minimum diameter of 6 by 3.5 feet (1.8 by 1.1 m) and 300 US gallons (1,100 L; 250 imp gal) is suggested as a bare minimum but 400–800 US gallons (1,500–3,000 L; 330–670 imp gal) is the best way to go. Australian species are best kept alone in aquaria. It
247-470: The family: The Phareodontinae is sometimes treated as a valid family, the Phareodontidae, proposed by Jordan in 1925. [REDACTED] [REDACTED] Arowana Arowanas are freshwater bony fish of the subfamily Osteoglossinae , also known as bony tongues (the latter name is now often reserved for Arapaiminae ). In this family of fish, the head is bony and the elongated body
266-687: The formation of fresh seabed in the proto-Atlantic Ocean. Plate tectonic activity in subduction zones caused the construction of north-south mountain ranges such as the Rocky Mountains and the Andes all along the west coast of North, Central, and South America. The Middle Jurassic is one of the key periods in the history of life on Earth. Many groups, including dinosaurs and mammals , diversified during this time. During this time, marine life (including ammonites and bivalves ) flourished. Ichthyosaurs , although common, are reduced in diversity;
285-471: The nickname "water monkeys". Arowana species typically grow to around 2 to 3 feet (0.6 to 0.9 m) in captivity. Arowanas can be troublesome to keep as pets. They are expensive, require wide living space, are picky eaters, and need a lot of care. Arowanas are renowned for their aggressive behavior and personality. Several species of osteoglossids exhibit parental care. They build nests and protect their young after they hatch. All species are mouthbrooders ,
304-547: The parents holding sometimes hundreds of eggs in their mouths. The young may make several tentative trips outside the parent's mouth to investigate the surroundings before leaving permanently. Unlike most fishes that start reproducing at around six months of age, the arowana usually takes three to four years to reach sexual maturity. Depending on the classification system used, there are ten types of arowana commonly kept as pets: four from Asia , three from South America , two from Australia , and one from Africa . Asian arowana
323-691: The supercontinent of Gondwana during the Mesozoic , which split into different genera following its fragmentation. However, more recent studies have found that many of the closest extinct relatives to extant osteoglossid genera were marine fish, and thus that their current distribution likely originates from marine dispersal between different continents during the Paleogene . Incorporating both extant and extinct osteoglossids, at least four different colonizations of freshwater habitats from marine ones are predicted to have occurred. The following taxa are known from
342-467: The top marine predators, the pliosaurs , grew to the size of killer whales and larger (e.g. Pliosaurus , Liopleurodon ). Plesiosaurs became common at this time, and metriorhynchids first appeared. In the Jurassic seas, a wide range of animals swam. Cartilaginous and bony fish were plentiful. Large fish and marine reptiles were plentiful. Many of the major groups of dinosaurs emerged during
361-647: Was tectonically active as the Cimmerian plate continued to collide with Laurasia's southern coast, completely closing the Paleo-Tethys Ocean . A subduction zone on the coast of western North America continued to create the Ancestral Rocky Mountains .Significant subduction zones were active along practically all of the continental edges surrounding Pangea, as well as in southern Tibet, southeastern Europe, and other locations, to allow
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