The evolutionary ancestry of arthropods dates back to the Cambrian period. The group is generally regarded as monophyletic, and many analyses support the placement of arthropods with cycloneuralians (or their constituent clades) in a superphylum Ecdysozoa. Overall, however, the basal relationships of animals are not yet well resolved. Likewise, the relationships between various arthropod groups are still actively debated. Today, arthropods contribute to the human food supply both directly as food, and more importantly, indirectly as pollinators of crops. Some species are known to spread severe disease to humans, livestock, and crops. (Full article...)
The Lampyridae are a family of elateroid beetles with more than 2,000 described species, many of which are light-emitting. They are soft-bodied beetles commonly called fireflies, lightning bugs, or glowworms for their conspicuous production of light, mainly during twilight, to attract mates. Light production in the Lampyridae is thought to have originated as a warningsignal that the larvae were distasteful. This ability to create light was then co-opted as a mating signal and, in a further development, adult female fireflies of the genus Photuris mimic the flash pattern of the Photinus beetle in order to trap their males as prey.
Fireflies are found in temperate and tropical climates. Many live in marshes or in wet, wooded areas where their larvae have abundant sources of food. While all known fireflies glow as larvae, only some species produce light in their adult stage, and the location of the light organ varies among species and between sexes of the same species. Fireflies have attracted human attention since classical antiquity; their presence has been taken to signify a wide variety of conditions in different cultures and is especially appreciated aesthetically in Japan, where parks are set aside for this specific purpose. (Full article...)
Carcinosomatidae (the name deriving from the type genusCarcinosoma, meaning "crab body") is a family of eurypterids, an extinct group of aquatic arthropods. They were members of the superfamily Carcinosomatoidea, also named after Carcinosoma. Fossils of carcinosomatids have been found in North America, Europe and Asia, the family possibly having achieved a worldwide distribution, and range in age from the Late Ordovician to the Early Devonian. They were among the most marine eurypterids, known almost entirely from marine environments.
Carcinosomatids varied considerably in size, from species only a few centimetres in length to some of the largest known arthropods. The largest carcinosomatid species, Carcinosoma punctatum, reached lengths of at least 2.2 metres (7.2 ft) and rivalled the largest eurypterid of all, Jaekelopterus, in size. Morphologically, carcinosomatids were highly distinct from other eurypterids, known for their powerful and spiny set of forelimbs, a broad and rounded central body and a slender and tubular tail ending in a telson (the posteriormost division of the body) that was typically curved in some way. With these adaptations, the carcinosomatids were quite similar to scorpions, and the group may have helped contribute to the common name of eurypterids becoming 'sea scorpions'. The family contains four, possibly five, genera: Carcinosoma, Eocarcinosoma, Eusarcana, Rhinocarcinosoma and possibly the problematic genus Holmipterus.
It is unlikely that the carcinosomatids were strong and active swimmers, given their non-streamlined shape. It is more probable that they were nektobenthic (swimming near the bottom), possibly being top predators (given their size) or scavengers, digging for food or perhaps even burrowing and lying in wait as ambush predators. (Full article...)
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Insects are the only group of invertebrates that have evolved wings and flight. Insects first flew in the Carboniferous, some 300 to 350 million years ago, making them the first animals to evolve flight. Wings may have evolved from appendages on the sides of existing limbs, which already had nerves, joints, and muscles used for other purposes. These may initially have been used for sailing on water, or to slow the rate of descent when gliding.
Two insect groups, the dragonflies and the mayflies, have flight muscles attached directly to the wings. In other winged insects, flight muscles attach to the thorax, which make it oscillate in order to induce the wings to beat. Of these insects, some (flies and some beetles) achieve very high wingbeat frequencies through the evolution of an "asynchronous" nervous system, in which the thorax oscillates faster than the rate of nerve impulses.
The meat ant (Iridomyrmex purpureus), also known as the gravel ant or southern meat ant, is a species of antendemic to Australia. A member of the genus Iridomyrmex in the subfamily Dolichoderinae, it was described by British entomologist Frederick Smith in 1858. The meat ant is associated with many common names due to its appearance, nest-building behaviour and abundance, of which its specific name, purpureus, refers to its coloured appearance. It is among the best-known species of ant found throughout Australia; it occurs in almost all states and territories except for Tasmania. Its enormous distribution, aggression and ecological importance have made this ant a dominant species.
The meat ant is monomorphic (occurs in a particular form), although there is evidence that certain populations can be polymorphic. It is characterised by its dark-bluish body and red head. It is a medium to large species, measuring 6–12 mm (0.24–0.47 in). The workers and males are approximately the same sizes at 6–7 mm (0.24–0.28 in) and 8 mm (0.31 in), respectively. The queens are the largest and appear mostly black, measuring 12.7 mm (0.50 in). The iridescence in workers ranges from green or blue to plain green and purple, varying in different body parts and castes. Meat ants inhabit open and warm areas in large, oval-shaped mounds that are accompanied by many entrance holes. The nest area is always cleared of vegetation and covered with materials including gravel, pebbles and dead vegetation. They are also polydomous, where a colony may be established in a series of satellite nests connected by well-defined paths and trails. Satellite nests are constructed away from the main nest and nearby areas with valuable food sources so workers can exploit them.
Queens mate with a single male and colonies may have more than one queen until the workers arrive, where they both exhibit antagonism. It takes around one or two months for an individual egg to develop into an adult. Colonies range in size, varying between 11,000 individuals to over 300,000. The meat ant is a diurnal species (active throughout most of the day), especially when it is warm. It forages on trees and collects sweet substances such as honeydew and nectar, and also captures insects or collects the remains of animals. A number of predators eat these ants, including the short-beaked echidna (Tachyglossus aculeatus), numerous species of birds, blind snakes and spiders. This species is also a competitor of the banded sugar ant (Camponotus consobrinus). Meat ants establish territorial borders with neighbouring colonies and solve disputes through ritualised fighting. (Full article...)
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Black-headed sugar ant worker from Strangways, Victoria
The black-headed sugar ant (Camponotus nigriceps), also known as the brown sugar ant, is a species of Formicinaeant endemic to Australia. Found throughout most states, the species is a member of the genus Camponotus, a cosmopolitan genus of ants commonly known as carpenter ants. It was formally described and named by British entomologist Frederick Smith in 1858. These ants are characterised by their black head, reddish-brown mesosoma and black gaster, which can change in colour.
The species is polymorphic: workers and soldiers measure 6 to 12 millimetres (0.24 to 0.47 in) and males are 12 millimetres (0.47 in). The queens are the largest members of the colony, measuring 16 millimetres (0.63 in). Colonies dwell in dry regions, including open areas or in dry sclerophyll woodland, where they nest in soil, large mounds or under stones. Nuptial flight occurs in summer and nests can hold several thousand individuals. Considered a household pest, black-headed sugar ants feed on sweet foods and insects and tend to butterfly larvae. Numerous birds and fish prey on these ants. (Full article...)
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Calliphora vomitoria, known as the blue bottle fly, orange-bearded blue bottle, or bottlebee, is a species of blow fly, a species in the family Calliphoridae. Calliphora vomitoria is the type species of the genusCalliphora. It is common throughout many continents including Europe, Americas, and Africa. They are fairly large flies, nearly twice the size of the housefly, with a metallic blue abdomen and long orange setae on the gena.
While adult flies feed on nectar, females deposit their eggs on rotting corpses, making them important forensic insects, as their eggs and timing of oviposition can be used to estimate time of death. (Full article...)
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Interpretive drawing of PIN 1271/2, the holotype of Dvulikiaspis menneri
Its prosoma (head) was subquadrate (almost square) to parabolic (nearly U-shaped), with (bean-shaped) to subovate (nearly oval) eyes and surrounded by a marginal rim. The abdomen was composed by a fused buckler and a postabdomen that occupied most of the body length, while the telson (the posteriormost division of the body) was small and semicircular in shape. The appendages (limbs) were uniform. The sixth and last pair of them had a paddle-like shape and was placed in front of the midpoint of the prosoma. The largest specimen was 2.64 centimetres (1.04 inches) long.
The first fossil was described in 1959 as a new species of the eurypteridStylonurus, while the other two were discovered in 1974. It would not be until 2014 when D. menneri was recognized as a chasmataspidid genus, being placed in the familyDiploaspididae. However, Dvulikiaspis was similar to Loganamaraspis and especially Hoplitaspis, with which it could form a new separate family of chasmataspidids. (Full article...)
Coccinellidae (/ˌkɒksɪˈnɛlɪdiː/) is a widespread family of small beetles. They are commonly known as ladybugs in North America and ladybirds in the United Kingdom; "lady" refers to mother Mary. Entomologists use the names ladybird beetles or lady beetles to avoid confusion with true bugs. The more than 6,000 described species have a global distribution and are found in a variety of habitats. They are oval beetles with a domed back and flat underside. Many of the species have conspicuous aposematic (warning) colours and patterns, such as red with black spots, that warn potential predators that they taste bad.
Most coccinellid species are carnivorous predators, preying on insects such as aphids and scale insects. Other species are known to consume non-animal matter, including plants and fungi. They are promiscuous breeders, reproducing in spring and summer in temperate regions and during the wet season in tropical regions. Many predatory species lay their eggs near colonies of prey, providing their larvae with a food source. Like most insects, they develop from larva to pupa to adult. Temperate species hibernate and diapause during the winter; tropical species are dormant during the dry season. Coccinellids migrate between dormancy and breeding sites.
Species that prey on agricultural pests are considered beneficial insects. Several species have been introduced outside their range as biological control agents, with varying degrees of success. Some species are pests themselves and attack agricultural crops, or can infest people's homes, particularly in winter. Invasive species like Harmonia axyridis can pose an ecological threat to native coccinellid species. Other threats to coccinellids include climate change and habitat destruction. These insects have played roles in folklore, religion and poetry, and are particularly popular in nursery rhymes. (Full article...)
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Andreacarus voalavo is a parasiticmite found on the Malagasy rodent Voalavo gymnocaudus. First described in 2007, it is closely related to Andreacarus gymnuromys and Andreacarus eliurus, which are found on other Malagasy rodents. The length of the idiosoma, the main body, is 630 to 670 μm in females and 450 to 480 μm in males. Unlike A. eliurus, this species lacks distinct sternal glands (secretory organs) between two lyrifissures (sensory organs) on the lower part of the female body. The pilus dentilis, a sensory organ on the chelicera, is serrate, which distinguishes it from A. gymnuromys. Females of A. gymnuromys also have a less ornamented sternal shield (covering part of the underparts) and shorter setae (bristles) on the upperparts. (Full article...)
Damselflies are flying insects of the suborder Zygoptera in the order Odonata. They are similar to dragonflies (which constitute the other odonatan suborder, Anisoptera) but are usually smaller and have slimmer bodies. Most species fold the wings along the body when at rest, unlike dragonflies which hold the wings flat and away from the body. Damselflies have existed since the Late Jurassic, and are found on every continent except Antarctica.
All damselflies are predatory insects; both nymphs and adults actively hunt and eat other insects. The nymphs are aquatic, with different species living in a variety of freshwater habitats including acidic bogs, ponds, lakes and rivers. The nymphs moult repeatedly, at the last moult climbing out of the water to undergo metamorphosis. The skin splits down the back, they emerge and inflate their wings and abdomen to gain their adult form. Their presence on a body of water indicates that it is relatively unpolluted, but their dependence on freshwater makes them vulnerable to damage to their wetland habitats.
Some species of damselfly have elaborate courtship behaviours. Many species are sexually dimorphic, the males often being more brightly coloured than the females. Like dragonflies, they reproduce using indirect insemination and delayed fertilisation. A mating pair form a shape known as a "heart" or "wheel", the male clasping the female at the back of the head, the female curling her abdomen down to pick up sperm from secondary genitalia at the base of the male's abdomen. The pair often remain together with the male still clasping the female while she lays eggs within the tissue of plants in or near water using a robust ovipositor. (Full article...)
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Theridion grallator, also known as the Hawaiian happy-face spider, is a spider in the familyTheridiidae that resides on the Hawaiian Islands. T. grallator gets its vernacular name of "Hawaiian happy-face spider" from the unique patterns superimposed on its abdomen, specifically those that resemble a human smiling face. T. grallator is particularly notable because of its wide range of polymorphisms that may be studied to allow a better understanding of evolutionary mechanisms. In addition to the variety of color polymorphisms present, T. grallator demonstrates the interesting quality of diet-induced color change, in which its appearance temporarily changes as it metabolizes various food items. (Full article...)
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Restoration of H. banksii
Herefordopterus is a genus of eurypterid, an extinct group of aquatic arthropods. Herefordopterus is classified as part of the family Hughmilleriidae, a basal family in the highly derived Pterygotioidea superfamily of eurypterids. Fossils of the single and type species, H. banksii, have been discovered in deposits of Silurian age in Herefordshire and Shropshire, England. The genus is named after Herefordshire, where most of the Herefordopterus fossils have been found. The specific epithet honors Richard Banks, who found several well-preserved specimens, including the first Herefordopterus fossils.
Herefordopterus is classified in Hughmilleriidae, a pterygotioid family that is differentiated by their streamlined bodies, the enlargement of its medium-sized chelicerae and the presence of paired spines on the walking appendages. It was distinguished for combining characteristics of Hughmilleria with those of the derived pterygotioids, showing a more advanced morphology than that of Hughmilleria. With the biggest specimen measuring 12 centimetres (5 inches) in length, Herefordopterus is considered a eurypterid of small size. (Full article...)
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The type material of E. clevelandi: a body segment (top; with zoomed-in detail of the integument) and an endognathary appendage (bottom)
Echinognathus is a genus of eurypterid, an extinct group of aquatic arthropods. The type and only species of Echinognathus, E. clevelandi, is known from deposits of Late Ordovician age in the United States. The generic name is derived from the Neo-Latinechino- ("spiny") and the Greekgnáthos ("jaw"), in reference to a spiny endognathary (used to handle food) appendage part of the fossil type material.
Echinognathus is only known from fragmentary fossil material, consisting of body segments, an appendage used to handle food and possibly other body segments. The genus is distinguished from other eurypterids by the large number of elongated and curved spines, blade-like in life, on its limbs. Initially assumed to represent a species of Eurypterus, these distinguishing features were quickly noticed and deemed important enough to designate Echinognathus as its own genus. With some additional fossil assigned to Echinognathus in the early 20th century, the genus was noted to be similar to Megalograptus, another eurypterid with spiny limbs. In 1955, Echinognathus and Megalograptus were placed into their own taxonomic family of eurypterids, the Megalograptidae.
Based on the proportions of other eurypterids, Echinognathus would have been a medium-sized predator, reaching approximately 45 centimeters (17.7 in) in length. The spines on its limbs were presumably used for active prey capture, securing food and carrying it to the mouth. The fossils of Echinognathus are known from what was once marine environments, and it lived alongside a fauna including graptolites, brachiopods, cephalopods and trilobites. (Full article...)
C. maenas is a widespread invasive species, listed among the 100 of the World's Worst Invasive Alien Species. It is native to the north-east Atlantic Ocean and Baltic Sea, but has colonised similar habitats in Australia, South Africa, South America and both Atlantic and Pacific coasts of North America. It grows to a carapace width of 90 mm (3+1⁄2 in), and feeds on a variety of mollusks, worms, and small crustaceans, affecting a number of fisheries. Its successful dispersal has occurred by a variety of mechanisms, such as on ships' hulls, sea planes, packing materials, and bivalves moved for aquaculture. (Full article...)
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Male Maevia inclemens - gray morph
Maevia inclemens or the dimorphic jumping spider is a relatively common and colorful jumping spider of North America. In the males there are two forms, a very rare phenomenon in zoology. These use different courting displays, and differ in appearance: the "tufted" morph has a black body and pedipalps ("palps"), three black tufts across its "head", and pale legs; and the "gray" morph has black and white stripes all over its body and legs, orange palps, and no tufts. However, each form accounts for 50% of the adult males, and they are equally successful in mating. A female of Maevia inclemens is 6.5 to 8.0 millimetres (0.26 to 0.31 in) long, while males are 4.75 to 6.50 millimetres (0.187 to 0.256 in) long.
Like all jumping spiders, M. inclemens has excellent vision. The main eyes, in the front-and-center position, are large, and are more acute than those of a cat and about 10 times as acute as a dragonfly's. The remaining three pairs of eyes are along the sides of the head, and work as motion detectors. The eyes are used for hunting, for avoiding threats and for finding mates.
Maevia inclemens is one of the eight species in genusMaevia. The species was first called Attus inclemens, and other names have been used. The two male forms look and behave so differently that they were originally considered two distinct species. In 1955 Robert Barnes chose M. inclemens, and this has become the standard name. (Full article...)
The following are images from various arthropod-related articles on Wikipedia.
Image 1Mature queen of a termite colony, showing how the unsclerotised cuticle stretches between the dark sclerites that failed to stretch as the abdomen grew to accommodate her ovaries (from Arthropod exoskeleton)
Image 4Formation of anterior segments across arthropod taxa based on gene expression and neuroanatomical observations, Note the chelicera(Ch) and chelifore(Chf) arose from somite 1 and thus correspond to the first antenna(An/An1) of other arthropods. (from Chelicerata)
Image 5This Zoea-stage larva is hardly recognisable as a crab, but each time it sheds its cuticle it remodels itself, eventually taking on its final crab form (from Arthropod exoskeleton)
Image 10Ghost crab, showing a variety of integument types in its exoskeleton, with transparent biomineralization over the eyes, strong biomineralization over the pincers, and tough chitin fabric in the joints and the bristles on the legs (from Arthropod exoskeleton)
Image 14Some of the various hypotheses of myriapod phylogeny. Morphological studies (trees a and b) support a sister grouping of Diplopoda and Pauropoda, while studies of DNA or amino acid similarities suggest a variety of different relationships, including the relationship of Pauropoda and Symphyla in tree c. (from Myriapoda)
Image 17The house centipedeScutigera coleoptrata has rigid sclerites on each body segment. Supple chitin holds the sclerites together and connects the segments flexibly. Similar chitin connects the joints in the legs. Sclerotised tubular leg segments house the leg muscles, their nerves and attachments, leaving room for the passage of blood to and from the hemocoel (from Arthropod exoskeleton)
Image 25 Honeybee larvae have flexible but delicate unsclerotised cuticles. (from Arthropod exoskeleton)
Image 26 This fully-grown robber crab has tough fabric forming its joints, delicate biomineralized cuticle over its sensory antennae, optic-quality over its eyes, and strong, calcite-reinforced chitin armouring its body and legs; its pincers can break into coconuts (from Arthropod exoskeleton)
Image 32In honeypot antrepletes, the abdomens of the workers that hold the sugar solution grow vastly, but only the unsclerotised cuticle can stretch, leaving the unstretched sclerites as dark islands on the clear abdomen (from Arthropod exoskeleton)
The light blue soldier crab (Mictyris longicarpus) inhabits beaches in the Indo-Pacific region. Soldier crabs filter sand or mud for microorganisms. They congregate during the low tide, and bury themselves in a corkscrew pattern during high tide, or whenever they are threatened.
Zonocerus variegatus, the variegated grasshopper, is a species of grasshopper in the family Pyrgomorphidae native to tropical western and central Africa. It feeds on a wide variety of plant foods and causes damage to crops, particularly cassava, groundnuts and vegetables, as well as transmitting diseases caused by mosaic viruses between plants. This Z. variegatus grasshopper was photographed in the Bobiri Forest in Ghana.
The Forest scorpion (Cercophonius squama) is a scorpion native to southeastern Australia and Tasmania. The body is 25 to 40 millimetres (0.98 to 1.57 in) long, and coloured creamy yellow to orange brown with dark brown variegations. The legs are yellow with some dark brown pigment.
The orb-weaver spiders (family Araneidae) are the familiar builders of spiral wheel-shaped webs often found in gardens, fields and forests. The family is a large one, including over 2800 species in over 160 genera worldwide, making it the third largest known (behind Salticidae and Linyphiidae). The web has always been thought of as an engineering marvel.
The Ozyptila praticola species of crab spider is found throughout Europe and the Middle East. They do not build webs to trap prey, but are active hunters. Crab spiders are so named because of their first two pairs of legs, which are held out to the side giving them a crab-like appearance. Also, like crabs, these spiders move sideways and backwards more easily than forwards.
Two flesh-flies (Sarcophaga ruficornis species pictured) mating. The life cycle of the saprophagic flesh-fly larvae has been well researched and is very predictable. Different species prefer bodies in different states of decomposition, which allows forensic entomologists to extrapolate the time of death.
Sexual dimorphism is the condition where the two sexes of the same species exhibit different characteristics. Differences may include secondary sex characteristics, size, weight, color, or markings, as well as behavioral and cognitive differences. In the butterfly species Colias dimera (also known as the Dimera sulphur), seen here mating in Venezuela, the male on the right is a brighter shade of yellow than the female.
The Painted Lady (Vanessa cardui) is a well-known colourful butterfly, found on every continent except Antarctica. It occurs in any temperate zone, including mountains in the tropics. The species is resident only in warmer areas, but migrates in spring, and sometimes again in autumn.
The head of a female Clynotis severus species of jumping spider. The eyes of a spider are called simple eyes (as opposed to compound eyes) because in each eye, a single lens collects and focuses light onto the retina. In this spider, the two largest eyes in the middle are the most acute. The remainder on the sides and on the top of its head are "secondary eyes".
The citrus root weevil (Diaprepes abbreviatus) is a major agricultural pest weevil in several Caribbean countries and the U.S. state of Florida. The larvae feed on the roots of the host plant for several months. They often eat the taproot of the plant, which can kill it by depriving it of water and nutrients or by making it vulnerable to infection by fungi, or water moulds.
Xylotrupes socrates (Siamese rhinoceros beetle, or "fighting beetle"), male, on a banana leaf. This scarab beetle is particularly known for its role in insect fighting in Northern Laos and Thailand.
Anthidium florentinum, a species of bee in the family Megachilidae. Bees are flying insects closely related to wasps and ants that are involved in pollination. There are nearly 20,000 known species of bees in seven recognized biological families. Bees are found on every continent except Antarctica, in every habitat on the planet that contains insect-pollinated flowering plants. Bees range in size from tiny stingless bee species whose workers are less than 2 millimetres (0.08 in) long, to Megachile pluto, whose females can attain a length of 39 millimetres (1.54 in).
The red rock crab (Grapsus grapsus), also known as "Sally Lightfoot", is one of the commonest crabs along the western seaboard of the Americas. John Steinbeck wrote of them, "Everyone who has seen them has been delighted with them ... These little crabs, with brilliant cloisonné carapaces, walk on their tiptoes, they have remarkable eyes and an extremely fast reaction time." He tried to catch them but to little avail. "If you walk slowly, they move slowly ahead of you in droves. If you hurry, they hurry. When you plunge at them, they seem to disappear in a puff of blue smoke."
Attacus taprobanis is a species of moth in the family Saturniidae native to southern India and Sri Lanka. This adult male, photographed in Kadavoor, Kerala, developed from a larva feeding on a mahogany tree. When ready to pupate, the larva formed a papery cocoon 7.5 cm (3 in) long interwoven with a leaf; before doing this, the larva had attached the leaf to the stem with a silken thread and cut the leaf stalk. The colours of the dying leaf provided camouflage for the pupa, and the adult insect emerged some 24 days later.
The western honey bee (Apis mellifera) is the most common of the 7–12 species of honey bee worldwide. It is believed to have originated in either Africa or Asia, and spread naturally through Africa, the Middle East and Europe. Following human introduction into the Americas and Oceania, the species is now found on every continent except Antarctica. Humans have been collecting honey from bees for thousands of years, with evidence in the form of rock art found in France and Spain, dating to around 7000 BC. Along with other insects, the honey bee is an important pollinator, with a large number of the crop species farmed worldwide depending on it.
The European paper wasp (Polistes dominula or Polistes dominulus) is one of the most common species of wasps in the genus Polistes. Originally described in 1791 by German naturalist Johann Ludwig Christ as Vespa dominula, it is native to southern Europe and North Africa, as well as temperate parts of Asia as far east as China. It has also been introduced to Australia, New Zealand, South Africa and the Americas. The species is common and cosmopolitan due to its exceptional survival features, such as a productive colony cycle, a short development time and a higher ability to endure predator attacks. It generally lives in temperate, terrestrial habitats, such as chaparral, forest and grassland biomes.
This picture shows a young European paper wasp queen guarding her nest and eggs.
Gonepteryx rhamni, also known as the common brimstone, is a butterfly in the family Pieridae. It lives throughout the Palearctic zone and is commonly found across Europe, Asia and North Africa. The butterfly relies on two species of buckthorn as hosts for its eggs and larvae, which influences its geographic range and distribution as these plants are commonly found in wetlands. After spending the summer feeding, adults travel to woodland areas to spend seven months hibernating. In spring when their host plants have developed, they return to the wetlands to breed and lay eggs. Both the larval and adult forms of the species have protective coloration and behaviour that decreases their chances of being recognised and preyed upon. The adult common brimstone has sexual dichromism in its wing coloration and iridescence; the male (pictured) has yellow wings and iridescence, while females have greenish-white wings and are not iridescent.
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