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Opisthoteuthis Agassizii
''Opisthoteuthis agassizii'' is a lesser-known, deep-sea octopus first described in 1883 by Addison E. Verrill. Like all cirrate octopuses, ''O. agassizii'' has fleshy fins to aid in swimming and a small internal shell. Males are up to four times heavier than females, and their suckers are proportionally larger. Both sexes are small. This species is found found in the north-west, and western Atlantic coasts, over depths of 277 to 1,935 meters (historic records from east Atlantic coasts were likely misidentifications with other ''Opisthoteuthis''). Like other opisthoteuthids, they occupy the benthic zone, living on or near the seafloor. These octopuses most likely prey on polychaete worms and crustaceans that live on or just above the seafloor. All females of ''O. agassizii'' become sexually mature when they reach 190 grams (6.702 oz.) and all males are sexually mature once they reach 95 g (3.351 oz.). However, both sexes continue to grow after they reach maturity. While ''O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Addison Emery Verrill
Addison Emery Verrill (February 9, 1839 – December 10, 1926) was an American invertebrate zoologist, museum curator and university professor. Life Verrill was born on February 9, 1839 in Greenwood, Maine, the son of George Washington Verrill and Lucy (Hillborn) Verrill. As a boy he showed an early interest in natural history, building collections of rocks and minerals, plants, shells, insects and other animals. When he moved with his family to Norway, Maine at age fourteen he attended secondary school at the Norway Liberal Institute. Verrill started college in 1859 at Harvard University and studied under Louis Agassiz. He graduated in 1862 with a B.A. He went on scientific collecting trips with Alpheus Hyatt and Nathaniel Shaler in the summer of 1860 to Trenton Point, Maine and Mount Desert Island and in the summer of 1861 to Anticosti Island and Labrador. In 1864 Verrill made reports on mining, or prospective mining, properties in New Hampshire, New York, and Pennsylvania. Tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oocyte
An oocyte (, ), oöcyte, or ovocyte is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female germ cells produce a primordial germ cell (PGC), which then undergoes mitosis, forming oogonia. During oogenesis, the oogonia become primary oocytes. An oocyte is a form of genetic material that can be collected for cryoconservation. Formation The formation of an oocyte is called oocytogenesis, which is a part of oogenesis. Oogenesis results in the formation of both primary oocytes during fetal period, and of secondary oocytes after it as part of ovulation. Characteristics Cytoplasm Oocytes are rich in cytoplasm, which contains yolk granules to nourish the cell early in development. Nucleus During the primary oocyte stage of oogenesis, the nucleus is called a germinal vesicle. The only normal human type of secondary oocyte has t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molluscs Described In 1883
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is estimated between 60,000 and 100,000 additional species. The proportion of undescribed species is very high. Many taxa remain poorly studied. Molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats. They are highly diverse, not just in size and anatomical structure, but also in behaviour and habitat. The phylum is typically divided into 7 or 8 taxonomic classes, of which two are entirely extinct. Cephalopod molluscs, such as squid, cuttlefish, and octopuses, are among the most neurologically advanced of all invertebrates—and either the giant squid or the colossal squid is the largest known invertebrate species. The gastropods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octopuses
An octopus ( : octopuses or octopodes, see below for variants) is a soft-bodied, eight- limbed mollusc of the order Octopoda (, ). The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like other cephalopods, an octopus is bilaterally symmetric with two eyes and a beaked mouth at the center point of the eight limbs. The soft body can radically alter its shape, enabling octopuses to squeeze through small gaps. They trail their eight appendages behind them as they swim. The siphon is used both for respiration and for locomotion, by expelling a jet of water. Octopuses have a complex nervous system and excellent sight, and are among the most intelligent and behaviourally diverse of all invertebrates. Octopuses inhabit various regions of the ocean, including coral reefs, pelagic waters, and the seabed; some live in the intertidal zone and others at abyssal depths. Most species grow quickly, mature early, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Biology (journal)
''Marine Biology'' is a peer-reviewed scientific journal covering research on all aspects of marine biology. The journal was established in 1967 and is published monthly by Springer Science+Business Media. The editor-in-chief is Ulrich Sommer ( Helmholtz Centre for Ocean Research). According to the ''Journal Citation Reports'', the journal has a 2014 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 2.391. References External links * Biology journals Springer Science+Business Media academic journals English-language journals Publications established in 1967 Marine biology Monthly journals Hybrid open access journals {{biology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opisthoteuthis Grimaldii
''Opisthoteuthis grimaldii'' is an octopus found near the Azores. ''O. grimaldii'' lives in the Northeast Atlantic Ocean from deep. This species lives far deeper than other Opisthoteuthis members in the Atlantic. The type specimen, upon which the species' description was based, was captured near Faial Island. The octopus has been found as far south as Namibian waters and as far north as British waters. In the early 1900s, many octopuses living all over the Atlantic and Indian oceans were classed as ''Opisthoteuthis grimaldii'', but later scientists decided that only those specimens found in the Eastern Atlantic Ocean actually belonged to the species. This octopus occupies in the bathyal zone, a deep area of the ocean where no sunlight reaches. Like many other cirrate octopuses, it lives on or just above the seafloor. ''Opisthoteuthis grimaldii'' is anatomically very similar to ''Opisthoteuthis borealis'', but the two species have differently structured digestive systems. It h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opisthoteuthis Massyae
''Opisthoteuths massyae'' is an octopus living in the eastern Atlantic Ocean. ''O. massyae'' occupies the benthic zone (seafloor and water immediately above) of the open ocean. The octopus lives from to deep. It's found as far north as Ireland, in the Rockall Basin, and as far south as Namibia. There are more specimens in the southeast Atlantic than in the northeast Atlantic. The two foremost arms of mature males are thicker than their other six arms. This is unusual for ''Opisthoteuthis'' species. Mature males also have some enlarged suckers, which is more typical of the genus. Males have more suckers than females. Specimens with longer arms generally have more suckers. Males weigh more than females; males can reach a weight of , and females a weight of . Females may lay eggs throughout their lifetimes. ''O. massyae'' has the ability to invert or "balloon" their webs. ''O. massyae'' is a carnivore; it probably catches prey by enveloping small animals within its web, simila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opisthoteuthis Calypso
''Opisthoteuthis calypso'' is a species of genus ''Opisthoteuthis'', which are known as the Cirrina, cirrate octopuses. Octopuses in this genus are known as the flapjack octopuses and can be found in a variety of oceans across the world. Anatomy and morphology The species of this genus show distinctive characteristics among the class Cephalopoda, including an oval shaped body compressed along the longitudinal axis, a gelatinous consistence and a large interbarachil web. This species generally has a mantle length of 5 cm. This web is what has given them their common name "flapjack" or "pancake devil fish".Norman M., 2000. Cephalopods, a world guide. Conchbooks Hackenheim, Germany, 320 pp. Other distinctive features include the presence of two small fins on the mantle, an internal U-shaped shell that has a groove along its outer surface. This particular species has eight, subequal arms (of an uneven length).Villanueva, Roger, Michael Vecchione, and Richard E. Young. 2006. Opi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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