| Anurida maritima | |
|---|---|
 | |
| An aggregation of A. maritima | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Collembola |
| Order: | Poduromorpha |
| Family: | Neanuridae |
| Genus: | Anurida |
| Species: | A. maritima |
| Binomial name | |
| Anurida maritima | |
| Synonyms [2] | |
Lipura maritima(Guérin-Méneville, 1836) | |
Anurida maritima, the seashore springtail, is a cosmopolitan collembolan of the intertidal zone. It is often found in aggregations of up to several hundred on the surface of rock-pools.
Anurida maritima is a wingless animal, typically up to 3 mm long, and dark slaty blue in colour. [3] Its body is roundish, expanding slightly towards the rear. The head bears a pair of eyes and a single pair of antennae, the thorax comprises three body segments, each of which bears one pair of legs, while the abdomen comprises six segments. [3] The entire body is covered with white hydrophobic hairs which allow the animal to stay above the surface of the water on which it spends much of its life. Unlike other springtails, A. maritima cannot leap, since its furcula is vestigial. This is apparently because when other springtails are placed upon water, surface tension unfolds their furcula and renders them unable to jump, so it has probably been lost by disuse. [3]
Anurida. maritima is found around the world on rocky shores and tidal marshes. In the British Isles, it is missing from the north-east of Scotland and has not been recorded from south-east Ireland. It is also absent from the Baltic Sea. There have been suggestions that the animals found in northern Europe may be a different species from that found in the Mediterranean Sea. [4]
Anurida maritima is a significant scavenger of the upper intertidal zone, feeding on dead animals, chiefly crustaceans (including barnacles) and molluscs. [3]
Aggregation is an important aspect of collembolan biology, and A. maritima has been shown to produce an aggregating pheromone. [5] Like many intertidal animals, A. maritima moves in rhythm with the tidal cycle, and has an endogenous circatidal rhythm with a period of 12.4 hours, [5] using visual cues to orient themselves during their movements. [6]
In the warmer parts of its range, A. maritima is active throughout the year, but in cooler temperate regions, it is only active in the summer months, overwintering as eggs. [7]
Branchiopoda is a class of crustaceans. It comprises fairy shrimp, clam shrimp, Diplostraca, Notostraca, the Devonian Lepidocaris and possibly the Cambrian Rehbachiella. They are mostly small, freshwater animals that feed on plankton and detritus.
The order Diplura is one of three orders of non-insect hexapods within the class Entognatha. The name "diplura", or "two tails", refers to the characteristic pair of caudal appendages or filaments at the terminal end of the body.
A pheromone is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavior of the receiving individuals. There are alarm pheromones, food trail pheromones, sex pheromones, and many others that affect behavior or physiology. Pheromones are used by many organisms, from basic unicellular prokaryotes to complex multicellular eukaryotes. Their use among insects has been particularly well documented. In addition, some vertebrates, plants and ciliates communicate by using pheromones. The ecological functions and evolution of pheromones are a major topic of research in the field of chemical ecology.
Centipedes are predatory arthropods belonging to the class Chilopoda of the subphylum Myriapoda, an arthropod group which includes millipedes and other multi-legged animals. Centipedes are elongated segmented (metameric) creatures with one pair of legs per body segment. All centipedes are venomous and can inflict painful stings, injecting their venom through pincer-like appendages known as forcipules or toxicognaths, which are actually modified legs instead of fangs. Despite the name, no species of centipede has exactly 100 legs; the number of pairs of legs is an odd number that ranges from 15 pairs to 191 pairs.
Derocheilocarididae is a family of marine crustaceans that form part of the meiobenthos. It is the only family in the monotypic order Mystacocaridida, and the monotypic subclass Mystacocarida. These mystacocarids are less than 1 mm (0.04 in) long, and live interstitially in the intertidal zones of sandy beaches.
Mysida is an order of small, shrimp-like crustaceans in the malacostracan superorder Peracarida. Their common name opossum shrimps stems from the presence of a brood pouch or "marsupium" in females. The fact that the larvae are reared in this pouch and are not free-swimming characterises the order. The mysid's head bears a pair of stalked eyes and two pairs of antennae. The thorax consists of eight segments each bearing branching limbs, the whole concealed beneath a protective carapace and the abdomen has six segments and usually further small limbs.
Anostraca is one of the four orders of crustaceans in the class Branchiopoda; its members are referred to as fairy shrimp. They live in vernal pools and hypersaline lakes across the world, and they have even been found in deserts, ice-covered mountain lakes, and Antarctic ice. They are usually 6–25 mm (0.24–0.98 in) long. Most species have 20 body segments, bearing 11 pairs of leaf-like phyllopodia, and the body lacks a carapace. They swim "upside-down" and feed by filtering organic particles from the water or by scraping algae from surfaces, with the exception of Branchinecta gigas, or "giant fairy shrimp", which is itself a predator of other species of anostracans. They are an important food for many birds and fish, and some are cultured and harvested for use as fish food. There are 300 species spread across 8 families.
A hamus or hamulus is a structure functioning as, or in the form of, hooks or hooklets.
The Entognatha are a class of wingless and ametabolous arthropods, which, together with the insects, makes up the subphylum Hexapoda. Their mouthparts are entognathous, meaning that they are retracted within the head, unlike the insects. Entognatha are apterous, meaning that they lack wings. The class contains three orders: Collembola, Diplura and Protura. These three groups were historically united with the now-obsolete order Thysanura to form the class Apterygota, but it has since been recognized that the hexapodous condition of these animals has evolved independently from that of insects, and independently within each order. The orders might not be closely related, and Entognatha is now considered to be a paraphyletic group.
The furcula, or furca is a forked, tail-like appendage. It is present in most species of springtails, and in them it is attached ventrally to the fourth abdominal segment. The organ most often is present in species of Collembola that lives in the upper soil layers where it is used for jumping to avoid predators. While at rest, it is retracted under the abdomen and held there by a structure variously called the retinaculum or hamula, which in turn is located beneath the third abdominal segment. When the furcula escapes from retinaculum, it swings downwards and hits the substrate, propelling the springtail into the air. The animal does not use this mechanism for ordinary locomotion, but only for escaping from predators or severe stress.
Tardigrades, known colloquially as water bears or moss piglets, are a phylum of eight-legged segmented micro-animals. They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them Kleiner Wasserbär'little water bear'. In 1776, the Italian biologist Lazzaro Spallanzani named them Tardigrada, which means 'slow steppers'.
Springtails form the largest of the three lineages of modern hexapods that are no longer considered insects. Although the three orders are sometimes grouped together in a class called Entognatha because they have internal mouthparts, they do not appear to be any more closely related to one another than they are to all insects, which have external mouthparts.
Cryptopygus antarcticus, the Antarctic springtail, is a species of springtail native to Antarctica and Australia. Cryptopygus antarcticus average 1–2 millimetres (0.04–0.08 in) long and weigh only a few micrograms. Like other springtails, the Antarctic springtail has been found to be useful as a bioindicator of pollution and has been used to study microplastic pollution in Antarctica. They also tend aggregate, by signaling to other individuals via pheromones, especially when temperatures are low, to avoid a high water loss rate.
Orchesella cincta is a species of springtail present in North America and Europe. They average 4 millimetres (0.16 in) in length, which is extremely large as most springtails don’t grow past 1 millimetre. The specific name cincta means "belted" and refers to the distinctive colouration of the third abdominal segment.
Geukensia demissa is a species of mussel, a marine bivalve mollusk in the family Mytilidae, the true mussels. This species is native to the Atlantic coast of North America. The common names for this species include ribbed mussel, Atlantic ribbed marsh mussel and ribbed horsemussel. However, the common name ribbed mussel is also used for the Southern Hemisphere mussel Aulacomya atra. The appearance of the shell is grooved and oval in shape. The interior of this mussel is tinted purple.
Dicheirotrichus gustavii is a ground beetle which emerges from cracks or holes to feed on tidal salt marshes after dusk. Despite living in a coastal environment, it has no cycle of behaviour linked to the tides, simply scurrying for dry land when caught by the approaching sea. It will eat the larvae of another intertidal beetle, Bledius spectabilis, if they are left unprotected by the adult.
Hediste diversicolor, commonly known as a ragworm, is a polychaete worm in the family Nereididae. It lives in a burrow in the sand or mud of beaches and estuaries in intertidal zones in the north Atlantic. This species is used in research, but its classification is in dispute; in the literature, it is often classified as Nereis diversicolor. Its specific name "diversicolor" refers to the fact that its colour changes from brown to green as the breeding season approaches.
The subphylum Hexapoda or hexapods comprises the largest clade of arthropods and includes most of the extant arthropod species. It includes the crown group class Insecta, as well as the much smaller clade Entognatha, which includes three classes of wingless arthropods that were once considered insects: Collembola (springtails), Protura (coneheads) and Diplura. The insects and springtails are very abundant and are some of the most important pollinators, basal consumers, scavengers/detritivores and micropredators in terrestrial environments.
In biology, being semi-aquatic refers to various macroorganisms that live regularly in both aquatic and terrestrial environments. When referring to animals, the term describes those that actively spend part of their daily time in water, or land animals that have spent at least one life stages in aquatic environments. When referring to plants, the term describes land plants whose roots have adapted well to tolerate regular, prolonged submersion in water, as well as emergent and (occasionally) floating-leaved aquatic plants that are only partially immersed in water.
Communication occurs when an animal produces a signal and uses it to influences the behaviour of another animal. A signal can be any behavioural, structural or physiological trait that has evolved specifically to carry information about the sender and/or the external environment and to stimulate the sensory system of the receiver to change their behaviour. A signal is different from a cue in that cues are informational traits that have not been selected for communication purposes. For example, if an alerted bird gives a warning call to a predator and causes the predator to give up the hunt, the bird is using the sound as a signal to communicate its awareness to the predator. On the other hand, if a rat forages in the leaves and makes a sound that attracts a predator, the sound itself is a cue and the interaction is not considered a communication attempt.
| Authority control databases: National |
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