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 spider is medium-sized, with a carapace that is between 2.1 and 2.9 mm long and an abdomen that is between 2.2 and 4.7 mm in length. The female is larger than the male. The carapace is dark brown with a characteristic triangular pattern. The abdomen is light with a narrow brown stripe down the middle. The spinnerets and legs are yellow. The male spider has a short reproductive part called an embolus, which is missing a helper organ often found in other species, known as a secondary conductor. Additionally, the male has a straight spike, known as an apophysis, on a part of pedipalp called the tibia. The female, in contrast, has unique, very narrow fissure-like openings leading to its reproductive ducts. It also has special glands located in front of the reproductive openings.
Menemerus animatus is very similar in appearance to the related Menemerus davidi, differing in minor details like the presence of a white margin on underside of the carapace. Likewise, it can be distinguished from Menemerus semilimbatus by the long spines on its legs. Otherwise, it is hard to tell apart from other species in its genus without a study of its copulatory organs. (Full article...)
Spiders (orderAraneae) are air-breathing arthropods that have eight limbs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species diversity among all orders of organisms. Spiders are found worldwide on every continent except Antarctica, and have become established in nearly every land habitat. , 51,673 spider species in 136 families have been recorded by taxonomists. However, there has been debate among scientists about how families should be classified, with over 20 different classifications proposed since 1900.
Anatomically, spiders (as with all arachnids) differ from other arthropods in that the usual body segments are fused into two tagmata, the cephalothorax or prosoma, and the opisthosoma, or abdomen, and joined by a small, cylindrical pedicel. However, as there is currently neither paleontological nor embryological evidence that spiders ever had a separate thorax-like division, there exists an argument against the validity of the term cephalothorax, which means fused cephalon (head) and the thorax. Similarly, arguments can be formed against the use of the term "abdomen", as the opisthosoma of all spiders contains a heart and respiratory organs, organs atypical of an abdomen.
Unlike insects, spiders do not have antennae. In all except the most primitive group, the Mesothelae, spiders have the most centralized nervous systems of all arthropods, as all their ganglia are fused into one mass in the cephalothorax. Unlike most arthropods, spiders have no extensor muscles in their limbs and instead extend them by hydraulic pressure. (Full article...)
Phengaris rebeli (formerly Maculinea rebeli), common name mountain Alcon blue, is a species of butterfly in the family Lycaenidae. It was first found and described in Styria, Austria, on Mount Hochschwab around 1700. Although it was initially classified as a subspecies of P. alcon, a European researcher, Lucien A. Berger, designated it as a separate species in 1946. Genetic similarities between P. rebeli and P. alcon have led many researchers to argue that the two are the same species and differences are due to intraspecific variation.
Although P. rebeli is found across the Palearctic (see subspecies), it is difficult to determine the species' precise range due to confusion with P. alcon.
Behavioral ecologists have found its role as a brood parasite to be of particular interest as, unlike many brood parasites, it does not directly oviposit in the hosts' nests. P. rebeli parasitizes the colony ant speciesMyrmica schencki as a larva by using chemical mimicry to trick the ants into believing that they are ant larvae; thus, the ants bring P. rebelicaterpillars back to their nests and feed them. P. rebeli is dependent on the plant Gentiana cruciata early in its life cycle and is vulnerable to parasitism by Ichneumon eumerus while inside the nest of M. schencki. It was placed on the IUCN Red List in 2000 and is classified as a species vulnerable to extinction. (Full article...)
Prionomyrmecini is an anttribe belonging to the subfamily Myrmeciinae established by William Morton Wheeler in 1915. Two members are a part of this tribe, the extant Nothomyrmecia and the extinct Prionomyrmex. The tribe was once considered a subfamily due to the similarities between Nothomyrmecia and Prionomyrmex, but such reclassification was not widely accepted by the scientific community. These ants can be identified by their long slender bodies, powerful stingers and elongated mandibles. Fossil Prionomyrmecini ants were once found throughout Europe, possibly nesting in trees and preferring jungle habitats. Today, Prionomyrmecini is only found in Australia, preferring old-growth mallee woodland surrounded by Eucalyptus trees. Nothomyrmecia workers feed on nectar and arthropods, using their compound eyes for prey and navigational purposes. Owing to their primitive nature, they do not recruit others to food sources or create pheromone trails. Nothomyrmecia colonies are small, consisting of 50 to 100 individuals. (Full article...)
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The Colorado potato beetle (Leptinotarsa decemlineata) is also known as the Colorado beetle, the ten-striped spearman, the ten-lined potato beetle, or the potato bug. It is a major pest of potato crops. It is about 10 mm (3⁄8 in) long, with a bright yellow/orange body and five bold brown stripes along the length of each of its elytra. Native to the Rocky Mountains, it spread rapidly in potato crops across America and then Europe from 1859 onwards.
Lepidopteran species are characterized by more than three derived features. The most apparent is the presence of scales that cover the bodies, large triangular wings, and a proboscis for siphoningnectars. The scales are modified, flattened "hairs", and give butterflies and moths their wide variety of colors and patterns. Almost all species have some form of membranous wings, except for a few that have reduced wings or are wingless. Mating and the laying of eggs is normally performed near or on host plants for the larvae. Like most other insects, butterflies and moths are holometabolous, meaning they undergo complete metamorphosis. The larvae are commonly called caterpillars, and are completely different from their adult moth or butterfly forms, having a cylindrical body with a well-developed head, mandible mouth parts, three pairs of thoracic legs and from none up to five pairs of prolegs. As they grow, these larvae change in appearance, going through a series of stages called instars. Once fully matured, the larva develops into a pupa. A few butterflies and many moth species spin a silk casing or cocoon for protection prior to pupating, while others do not, instead going underground. A butterfly pupa, called a chrysalis, has a hard skin, usually with no cocoon. Once the pupa has completed its metamorphosis, a sexually mature adult emerges.
Lepidopterans first appeared in fossil record in the Triassic-Jurassic boundary and have coevolved with flowering plants since the angiosperm boom in the Middle/Late Cretaceous. They show many variations of the basic body structure that have evolved to gain advantages in lifestyle and distribution. Recent estimates suggest the order may have more species than earlier thought, and is among the five most species-rich orders (each with over 100,000 species) along with Coleoptera (beetles), Diptera (flies and mosquitos), Hymenoptera (ants, bees, wasps and sawflies) and Hemiptera (cicadas, aphids and other true bugs). They have, over millions of years, evolved a wide range of wing patterns and coloration ranging from drab moths akin to the related order Trichoptera, to the brightly colored and complex-patterned butterflies. Accordingly, this is the most recognized and popular of insect orders with many people involved in the observation, study, collection, rearing of, and commerce in these insects. A person who collects or studies this order is referred to as a lepidopterist. (Full article...)
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Female
Zygoballus sexpunctatus is a species of jumping spider which occurs in the southeastern United States where it can be found in a variety of grassy habitats. Adult spiders measure between 3 and 4.5 mm in length. The cephalothorax and abdomen are bronze to black in color, with reddish brown or yellowish legs. The male has distinctive enlarged chelicerae (the mouthparts used for grasping prey) and front femora (the third, and typically largest, leg segments). Like many jumping spiders, Z. sexpunctatus males exhibit ritualized courtship and agonistic behavior. (Full article...)
Pseudastacus (meaning "false Astacus", in comparison to the extant crayfish genus) is an extinct genus of decapod crustaceans that lived during the Jurassic period in Europe, and possibly the Cretaceous period in Lebanon. Many species have been assigned to it, though the placement of some species remains uncertain and others have been reassigned to different genera. Fossils attributable to this genus were first described by Georg zu Münster in 1839 under the name Bolina pustulosa, but the generic name was changed in 1861 after Albert Oppel noted that it was preoccupied. The genus has been placed into different families by numerous authors, historically being assigned to Nephropidae or Protastacidae. Currently, it is believed to be a member of Stenochiridae.
Reaching up to 6 cm (2.4 in) in total length, Pseudastacus was a small animal. Members of this genus have a crayfish-like build, possessing long antennae, a triangular rostrum and a frontmost pair of appendages enlarged into long and narrow pincers. Deep grooves are present on the carapace, which is around the same length as the abdomen. The surface of the carapace is usually uneven, with either small tubercles or pits. Sexual dimorphism is known in P. pustulosus, with the pincers of females being more elongated than those of the males. There is evidence of possible gregarious behavior in P. lemovices in the form of multiple individuals preserved alongside each other, possibly killed in a mass mortality event. With the oldest known record dating to the Sinemurian age of the Early Jurassic, and possible species surviving into the Cenomanian stage of the Late Cretaceous, Pseudastacus has a long temporal range and was a widespread taxon. Fossils of this animal were first found in the Solnhofen Limestone of Germany, but have also been recorded from France, England and Lebanon. All species in this genus lived in marine environments. (Full article...)
Myrmecia is a genus of ants first established by Danish zoologistJohan Christian Fabricius in 1804. The genus is a member of the subfamily Myrmeciinae of the family Formicidae. Myrmecia is a large genus of ants, comprising at least 93 species that are found throughout Australia and its coastal islands, while a single species is only known from New Caledonia. One species has been introduced out of its natural distribution and was found in New Zealand in 1940, but the ant was last seen in 1981. These ants are commonly known as bull ants, bulldog ants or jack jumper ants, and are also associated with many other common names. They are characterized by their extreme aggressiveness, ferocity, and painful stings. Some species are known for the jumping behavior they exhibit when agitated.
Species of this genus are also characterized by their elongated mandibles and large compound eyes that provide excellent vision. They vary in colour and size, ranging from 8 to 40 millimetres (0.31 to 1.57 in). While workers and queens are hard to distinguish from each other due to their similar appearance, males are identifiable by their perceptibly smaller mandibles. Almost all Myrmecia species are monomorphic, with little variation among workers of a given species. Some queens are ergatoid and have no wings, while others have either stubby or completely developed wings. Nests are mostly found in soil, but they can be found in rotten wood and under rocks. One species does not nest in the ground at all; its colonies can only be found in trees.
A queen will mate with one or more males, and during colony foundation she will hunt for food until the brood have fully developed. The life cycle of the ant from egg to adult takes several months. Myrmecia workers exhibit greater longevity in comparison to other ants, and workers are also able to reproduce with male ants. Myrmecia is one of the most primitive group of ants on earth, exhibiting differentiated behaviors from other ants. Workers are solitary hunters and do not lead other workers to food. Adults are omnivores that feed on sweet substances, but the larvae are carnivores that feed on captured prey. Very few predators eat these ants due to their sting, but their larvae are often consumed by blindsnakes and echidnas, and a number of parasites infect both adults and brood. Some species are also effective pollinators. (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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The bush coconut, or bloodwood apple, is an Australian bush tucker food. It is an insect gall with both plant and animal components: an adult female scale insect and her offspring (of genus Cystococcus) live in a gall induced on a bloodwood eucalypt tree (Corymbia). Bush coconuts can vary from golf ball to tennis ball size. They have a hard and lumpy outer layer. The inner layer is a white flesh that contains the female insect and her offspring. There are three known species of Cystococcus responsible for forming the bush coconut: Cystococcus pomiformis, Cystococcus echiniformis and Cystococcus campanidorsalis. C. pomiformis is the most common species. The bush coconut is found in Western Australia, the Northern Territory, Queensland and New South Wales.
The bush coconut is picked from the host tree and cracked open to allow the flesh and scale insects to be eaten. Both have a high protein content and are used as a food source by humans and other animals. The name 'bush coconut' is derived from the white flesh of the inner layer, which is similar in appearance to that of a coconut, and the taste of the flesh has been said to have a coconut flavour. The bush coconut has been depicted in Indigenous Australian dreaming and used as inspiration in their artwork. (Full article...)
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Dyspanopeus sayi is a species of mud crab that is native to the Atlantic coast of North America. It has also become established outside its native range, living in Swansea Docks since 1960, the Mediterranean Sea since the 1970s, the North Sea since 2007 and the Black Sea since 2010. It can reach a carapace width of 20 mm (0.8 in), and has black tips to its unequal claws. It feeds on bivalves and barnacles, and is in turn eaten by predators including the Atlantic blue crab, Callinectes sapidus. Eggs are produced from spring to autumn, the offspring reach sexual maturity the following summer, and individuals can live for up to two years. The closest relative of D. sayi is D. texanus, which lives in the Gulf of Mexico; the two species differ in subtle features of the genitalia and the last pair of walking legs. (Full article...)
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Locusts (derived from the Latinlocusta, locust or lobster) are various species of short-horned grasshoppers in the family Acrididae that have a swarming phase. These insects are usually solitary, but under certain circumstances they become more abundant and change their behaviour and habits, becoming gregarious. No taxonomic distinction is made between locust and grasshopper species; the basis for the definition is whether a species forms swarms under intermittently suitable conditions; this has evolved independently in multiple lineages, comprising at least 18 genera in 5 different subfamilies.
Normally, these grasshoppers are innocuous, their numbers are low, and they do not pose a major economic threat to agriculture. However, under suitable conditions of drought followed by rapid vegetation growth, serotonin in their brains triggers dramatic changes: they start to breed abundantly, becoming gregarious and nomadic (loosely described as migratory) when their populations become dense enough. They form bands of wingless nymphs that later become swarms of winged adults. Both the bands and the swarms move around, rapidly strip fields, and damage crops. The adults are powerful fliers; they can travel great distances, consuming most of the green vegetation wherever the swarm settles.
Locusts have formed plagues since prehistory. The ancient Egyptians carved them on their tombs and the insects are mentioned in the Iliad, the Mahabharata, the Bible and Quran. Swarms have devastated crops and have caused famines and human migrations. More recently, changes in agricultural practices and better surveillance of locust breeding grounds have allowed control measures at an early stage. Traditional locust control uses insecticides from the ground or air, but newer biological control methods are proving effective. Swarming behaviour decreased in the 20th century, but despite modern surveillance and control methods, swarms can still form; when suitable weather conditions occur and vigilance lapses, plagues can occur. (Full article...)
Grasshoppers are a group of insects belonging to the suborderCaelifera. They are amongst what are possibly the most ancient living groups of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago.
Grasshoppers are typically ground-dwelling insects with powerful hind legs which allow them to escape from threats by leaping vigorously. Their front leg is shorter and used for grasping food. As hemimetabolous insects, they do not undergo complete metamorphosis; they hatch from an egg into a nymph or "hopper" which undergoes five moults, becoming more similar to the adult insect at each developmental stage. The grasshopper hears through the tympanal organ which can be found in the first segment of the abdomen attached to the thorax; while its sense of vision is in the compound eyes, the change in light intensity is perceived in the simple eyes (ocelli). At high population densities and under certain environmental conditions, some grasshopper species can change colour and behavior and form swarms. Under these circumstances, they are known as locusts.
Grasshoppers are plant-eaters, with a few species at times becoming serious pests of cereals, vegetables and pasture, especially when they swarm in the millions as locusts and destroy crops over wide areas. They protect themselves from predators by camouflage; when detected, many species attempt to startle the predator with a brilliantly coloured wing flash while jumping and (if adult) launching themselves into the air, usually flying for only a short distance. Other species such as the rainbow grasshopper have warning coloration which deters predators. Grasshoppers are affected by parasites and various diseases, and many predatory creatures feed on both nymphs and adults. The eggs are subject to attack by parasitoids and predators. Grasshoppers are diurnal insects—meaning, they are most active during the day time. (Full article...)
Image 7The 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 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 11Crab larva barely recognisable as a crab, radically changes its form when it undergoes ecdysis as it matures (from Arthropod exoskeleton)
Image 13Some 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 14 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 15 Honeybee larvae have flexible but delicate unsclerotised cuticles. (from Arthropod exoskeleton)
Image 24This 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 25Mature 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 29In 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)
Image 31The fangs in spiders' chelicerae are so sclerotised as to be greatly hardened and darkened (from Arthropod exoskeleton)
Image 32Formation 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)
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.
The Polyphemus Moth (Anthera polyphemus) is one the biggest moths, having a wingspan of up to 15 cm. Usually found in forests, moths are notable for apparently being attracted to light, the reason for this behaviour is not known.
The Globe Skimmer (Pantala flavescens) is the most widespread dragonfly species on the planet, found between about the 40th parallels of latitude, or where the annual mean temperature is above 20 °C (68 °F), except in Europe where there are only occasional sightings.
Danaus genutia, the common tiger or striped tiger, is a species of brush-footed butterfly found in Sri Lanka, India, Myanmar, south-eastern Asia and Australia. It prefers areas of moderate to heavy rainfall, and typical habitats include scrubby jungle, deciduous forests and fallow land near habitations. The insect sequesters toxins from plants, and advertises its unpalatability by having prominent markings and striking colour patterns. This adult male common tiger, of the subspecies D. g. genutia, was photographed in Kerala, India.
Compound eyes on a blue bottle fly. Unlike simple eyes, which have a single concave photoreceptive surface, compound eyes consist of a number of individual lenses (called ommatidia) laid out on a convex surface; this means that they point in slightly different directions. Compound eyes provide a wide field of view and can detect fast movement, but have low resolution.
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.
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 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."
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.
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 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.
The Adonis blue (Polyommatus bellargus) is a butterfly in the family Lycaenidae, found in Europe and parts of West Asia. This photograph, taken in a chalk meadow at Yoesden Bank in Buckinghamshire, England, shows the underside of the folded wings of a male Adonis blue; the upper side is a bright, sky-blue.
A lithograph by Sidney Hall, published in Urania's Mirror, depicting the constellation Scorpius. One of the 48 constellations identified by the Greek astronomer Ptolemy in the second century, Scorpius lies between Libra to the west and Sagittarius to the east. It contains 18 main stars, the brightest of which is Antares. Although frequently identified as a scorpion, this constellation has also been likened to a "leaning coconut tree" (Java) or "Maui's fishhook" (Hawaii).
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.
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 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.
Two Melangyna viridiceps (called Common Hoverflies in Australia) mating in mid-air. The male, which can be identified by the eyes meeting at the top of its head, is on top. The term "hoverfly" refers to about 6,000 species of flying insects in the family Syrphidae. They are often seen hovering at flowers and are important pollinators.
A Eusthenia species of stonefly. The order contains almost 3,500 known species, including the only known insects that are exclusively aquatic from birth to death. Stoneflies are believed to be one of the most primitive groups of Neoptera and are found worldwide, with the exception of Antarctica.
Poli's stellate barnacle (Chthamalus stellatus) is a species of acorn barnacle common on rocky shores in South West England, Ireland, and Southern Europe. It is named after Italian scientist Giuseppe Saverio Poli. Depending upon environmental conditions and the amount of food available, it can reach up to 14 mm (0.55 in) in diameter.
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