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Squalus Hawaiiensis
''Squalus hawaiiensis'', the Hawaiian spurdog, is a dogfish, a member of the family Squalidae, found in waters surrounding the Hawaiian Islands, from the surface to 950 m. Its length is up to 75 cm. Taxonomy ''Squalus hawaiiensis'' was once lumped with the shortspine spurdog The shortspine spurdog (''Squalus mitsukurii'') is a dogfish, a member of the family Squalidae, found on continental shelves off Japan in temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to ..., but morphological and genetic data showed that the Hawaiian population was distinct from ''S. mitsukurii'' individuals from Japan to be considered a distinct species.Daly-Engel TS, Koch A, Anderson JM, Cotton CF, Grubbs RD (2018) Description of a new deep-water dogfish shark from Hawaii, with comments on the Squalus mitsukurii species complex in the West Pacific. ZooKeys 798: 135-157. https://doi.org/10.3897/zookeys.798.28375 References {{Taxonbar, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squaliformes
The Squaliformes are an order (biology), order of sharks that includes about 126 species in seven families. Members of the order have two dorsal fins, which usually possess spines, they usually have a sharp head, no anal fin or nictitating membrane, and five to seven gill slits. In most other respects, however, they are quite variable in form and size. Most species of the squaliform order live in saltwater or brackish water. They are found worldwide, from northern to tropical waters, and from shallow coastal seas to the open ocean. All members of the family Eptomeridae and Dalatiidae and ''Zameus squamulosus'' possess photophores, luminous organs, and exhibit intrinsic bioluminescence. Bioluminescence evolved once in Squaliformes, approximately 111–153 million years ago, and helped the Squaliformes radiate and adapt to the deep sea. The common ancestor of Dalatiidae, Etmopteridae, Somniosidae, and Oxynotidae possessed a luminous organ and used bioluminescence for camouf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squalidae
Squalidae, more commonly known as dogfish, dog sharks, or spiny dogfish, are one of several families of sharks categorized under Squaliformes, making it the second largest order of sharks, numbering 119 species across 7 families. Having earned their name after a group of fishermen reportedly observed the species chasing down smaller fish in dog-like packs, dogfish have slender, streamlined bodies, usually more compact in comparison to other species, and a pointed snout. Dogfish likewise have two dorsal fins, each with smooth spines, but no anal fin, and their skin is generally rough to the touch. As the species reaches adulthood, males usually measure a maximum of 39 inches (990 mm), while females typically measure 49 inches (1,200 mm) long. The species therefore exhibits female-dominant sexual dimorphism. Dogfish sharks have slate-gray or gray-brown skin with white dots that becomes paler (almost white) around the belly region. These sharks are characterized by teeth i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shortspine Spurdog
The shortspine spurdog (''Squalus mitsukurii'') is a dogfish, a member of the family Squalidae, found on continental shelves off Japan in temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout t ... waters, from the surface to 950 m. Its length is up to 75 cm. Taxonomy The shortspine dogfish was once seen as a circumglobal species by many authors, including Compagno (1984) and Last & Stevens (1994). However, a series on papers published since 2007 have shown that a number of species synonymized with ''S. mitsukurii'' are distinct, and that the Hawaiian population of ''S. mitsukurii'' represent a distinct species, the Hawaiian spurdog.Daly-Engel TS, Koch A, Anderson JM, Cotton CF, Grubbs RD (2018) Description of a new deep-water dogfish shark from Hawaii, with comments on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squalus
''Squalus'' is a genus of dogfish sharks in the family Squalidae. Commonly known as spurdogs, these sharks are characterized by smooth dorsal fin spines, teeth in upper and lower jaws similar in size, caudal peduncle with lateral keels; upper precaudal pit usually present, and caudal fin without subterminal notch. In spurdogs, the hyomandibula (the bone connecting the braincase to the jaws) is oriented at a right angle to the neurocranium, while in other sharks, the hyomandibula runs more parallel to the body. This led some to think that the upper jaw of ''Squalus'' would not be as protractile as the jaws of other sharks. However, a study that compared different jaw suspension types in sharks showed that this is not the case and that ''Squalus'' is quite capable of protruding its upper jaw during feeding.Wilga, C.D., Motta, P.J. & Sanford, C.P. (2007): Evolution and ecology of feeding in elasmobranchs. ''Integrative and Comparative Biology, 47 (1): 55-69.'' The name comes from '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
