|
Phylliroidae
The Phylliroidae are a family of nudibranch sea snails, highly adapted to a pelagic lifestyle and occurring in tropical surface waters around the globe. The two species of the genus ''Phylliroe'' and ''Cephalopyge trematoides'' that have been assigned to this family are small to average in size (up to ), slender and highly transparent. They swim by undulating their whole body. Their foot is very small, which helps to reduce drag. They are carnivores that prey on planktonic jelly fish Jellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella- .... References Further reading * * Powell A. W. B., ''New Zealand Mollusca'', William Collins Publishers Ltd, Auckland, New Zealand 1979 * oRMS listing for this family {{Taxonbar, from=Q43395 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylliroe Bucephalum
''Phylliroe bucephala'' is a parasitic species of pelagic nudibranch, a marine gastropod mollusc in the family Phylliroidae. Biology This species of nudibranch is transparent with its guts visible through the laterally flattened body. It has a tail and two long smooth rhinophores. It feeds on jellyfish and plankton as an adult. The juveniles parasitize ''Zanclea'' medusae Jellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella ....Gosliner TM, Valdes A Behrens DW 2015 ''Nudibranch and Sea Slug Identification Indo-Pacific'' New World Publications Jacksonville Florida USA References * Powell A. W. B., ''New Zealand Mollusca'', William Collins Publishers Ltd, Auckland, New Zealand 1979 SeaSlugForum {{Taxonbar, from=Q3200126 Phylliroidae Gastropods described in 1810 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephalopyge (gastropod)
''Cephalopyge trematoides'' is a pelagic species of nudibranch. A free-swimming marine gastropod in the family Phylliroidae. ''Cephalopyge trematoides'' is the only known species in its genus (i.e. the genus is monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...). Etymology Cephalopyge is a contraction of cephalus (Greek: κεφαλή , "head") and (πūγή, "behind") referring to the position of the anus close to the head. The species epithet trematoides expresses a likeness to flukes. Description ''C. trematoides'' grows to 2.5 cm in length. It swims at approximately 12 cm/s, by passing several undulatory waves down its body each second. It is flattened and transparent; its internal organs are visible.Marine species identification portalCephalopygean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephalopyge Trematoides
''Cephalopyge trematoides'' is a pelagic species of nudibranch. A free-swimming marine gastropod in the family Phylliroidae. ''Cephalopyge trematoides'' is the only known species in its genus (i.e. the genus is monotypic). Etymology Cephalopyge is a contraction of cephalus (Greek: κεφαλή , "head") and (πūγή, "behind") referring to the position of the anus close to the head. The species epithet trematoides expresses a likeness to flukes. Description ''C. trematoides'' grows to 2.5 cm in length. It swims at approximately 12 cm/s, by passing several undulatory waves down its body each second. It is flattened and transparent; its internal organs are visible.Marine species identification portalCephalopygeanCephalopyge trematoides Pelagic nudibranchs Of the approximately 3000 species of nudibranch, the vast majority are benthic, only a couple are neustonic, and ''C. trematoides'' is very unusual in that it is pelagic. It is estimated to be one of only f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylliroe
''Phylliroe'' is a genus of average sized (up to ), highly transparent pelagic nudibranchs, marine gastropod molluscs in the order Opisthobranchia, that consists of two known species. It is notable for being an open-ocean hunter that resembles a fish in body plan and locomotion, an example of convergent evolution. Distribution and habitat * ''P. atlantica'' occurs in the (sub) tropical waters of the Atlantic and Pacific oceans. * ''P. bucephalum'' is known from the Mediterranean. Ecology Juveniles of ''P. bucephalum'' are found exclusively feeding on the bell of the hydromedusa ''Zanclea costata'' (this junior synonym was given precedence over ''Mnestra parasites''). At first the nudibranch is attached to the inside of the bell of the meduse with its very small foot. It sucks tissue from the ring, radial canals and manubrium of the meduse and grows from 1.6 mm to 11 mm in just ten days, while the meduse shrinks. When the slug is as big as the meduse, it starts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Snails
Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the absence of a visible shell. Definition Determining whether some gastropods should be called sea snails is not always easy. Some species that live in brackish water (such as certain neritids) can be listed as either freshwater snails or marine snails, and some species that live at or just above the high tide level (for example species in the genus '' Truncatella'') are sometimes considered to be sea snails and sometimes listed as land snails. Anatomy Sea snails are a very large group of animals and a very diverse one. Most snails that live in salt water respire using a gill or gills; a few species, though, have a lung, are intertidal, and are active only at low tide when they can move around in the air. These air-breathing species in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adaptation
In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the population during that process. Thirdly, it is a phenotypic trait or adaptive trait, with a functional role in each individual organism, that is maintained and has evolved through natural selection. Historically, adaptation has been described from the time of the ancient Greek philosophers such as Empedocles and Aristotle. In 18th and 19th century natural theology, adaptation was taken as evidence for the existence of a deity. Charles Darwin proposed instead that it was explained by natural selection. Adaptation is related to biological fitness, which governs the rate of evolution as measured by change in allele frequencies. Often, two or more species co-adapt and co-evolve as they develop adaptations that interlock with those of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelagic
The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or water column between the surface of the sea and the bottom. Conditions in the water column change with depth: pressure increases; temperature and light decrease; salinity, oxygen, micronutrients (such as iron, magnesium and calcium) all change. Marine life is affected by bathymetry (underwater topography) such as the seafloor, shoreline, or a submarine seamount, as well as by proximity to the boundary between the ocean and the atmosphere at the ocean surface, which brings light for photosynthesis, predation from above, and wind stirring up waves and setting currents in motion. The pelagic zone refers to the open, free waters away from the shore, where marine life can swim freely in any direction unhindered by topographical constraints. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Niche
In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for example, by growing when resources are abundant, and when predators, parasites and pathogens are scarce) and how it in turn alters those same factors (for example, limiting access to resources by other organisms, acting as a food source for predators and a consumer of prey). "The type and number of variables comprising the dimensions of an environmental niche vary from one species to another ndthe relative importance of particular environmental variables for a species may vary according to the geographic and biotic contexts". See also Chapter 2: Concepts of niches, pp. 7 ''ff'' A Grinnellian niche is determined by the habitat in which a species lives and its accompanying behavioral adaptations. An Eltonian niche emphasizes that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drag (physics)
In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid friction) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers (or surfaces) or between a fluid and a solid surface. Unlike other resistive forces, such as dry friction, which are nearly independent of velocity, the drag force depends on velocity. Drag force is proportional to the velocity for low-speed flow and the squared velocity for high speed flow, where the distinction between low and high speed is measured by the Reynolds number. Even though the ultimate cause of drag is viscous friction, turbulent drag is independent of viscosity. Drag forces always tend to decrease fluid velocity relative to the solid object in the fluid's path. Examples Examples of drag include the component of the net aerodynamic or hydrodynamic force acting opposite to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnivores
A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other soft tissues) whether through hunting or scavenging. Nomenclature Mammal order The technical term for mammals in the order Carnivora is ''carnivoran'', and they are so-named because most member species in the group have a carnivorous diet, but the similarity of the name of the order and the name of the diet causes confusion. Many but not all carnivorans are meat eaters; a few, such as the large and small cats (felidae) are ''obligate'' carnivores (see below). Other classes of carnivore are highly variable. The Ursids, for example: While the Arctic polar bear eats meat almost exclusively (more than 90% of its diet is meat), almost all other bear species are omnivorous, and one species, the giant panda, is nearly exclusively herbivorou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planktonic
Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish and whales. Marine plankton include bacteria, archaea, algae, protozoa and drifting or floating animals that inhabit the saltwater of oceans and the brackish waters of estuaries. Freshwater plankton are similar to marine plankton, but are found in the freshwaters of lakes and rivers. Plankton are usually thought of as inhabiting water, but there are also airborne versions, the aeroplankton, that live part of their lives drifting in the atmosphere. These include plant spores, pollen and wind-scattered seeds, as well as microorganisms swept into the air from terrestrial dust storms and oceanic plankton swept into the air by sea spray. Though many plan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Sea Snails")
