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...)
Scale insects are small insects of the orderHemiptera, suborder Sternorrhyncha. Of dramatically variable appearance and extreme sexual dimorphism, they comprise the infraorder Coccomorpha which is considered a more convenient grouping than the superfamily Coccoidea due to taxonomic uncertainties. Adult females typically have soft bodies and no limbs, and are concealed underneath domed scales, extruding quantities of wax for protection. Some species are hermaphroditic, with a combined ovotestis instead of separate ovaries and testes. Males, in the species where they occur, have legs and sometimes wings, and resemble small flies. Scale insects are herbivores, piercing plant tissues with their mouthparts and remaining in one place, feeding on sap. The excess fluid they imbibe is secreted as honeydew on which sooty mold tends to grow. The insects often have a mutualistic relationship with ants, which feed on the honeydew and protect them from predators. There are about 8,000 described species.
The oldest fossils of the group date to the Late Jurassic, preserved in amber. They were already substantially diversified by the Early Cretaceous suggesting an earlier origin during the Triassic or Jurassic. Their closest relatives are the jumping plant lice, whiteflies, phylloxera bugs and aphids. The majority of female scale insects remain in one place as adults, with newly hatched nymphs, known as "crawlers", being the only mobile life stage, apart from the short-lived males. The reproductive strategies of many species include at least some amount of asexual reproduction by parthenogenesis.
Some scale insects are serious commercial pests, notably the cottony cushion scale (Icerya purchasi) on Citrus fruit trees; they are difficult to control as the scale and waxy covering protect them effectively from contact insecticides. Some species are used for biological control of pest plants such as the prickly pear, Opuntia. Others produce commercially valuable substances including carmine and kermes dyes, and shellac lacquer. The two red colour-names crimson and scarlet both derive from the names of Kermes products in other languages. (Full article...)
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Alice E. Gray (June 7, 1914–April 27, 1994) was an American entomologist and origamist. She worked as an entomologist at the American Museum of Natural History (AMNH) in New York for 43 years, writing, illustrating, and creating large models of insects. Known as the "Bug Lady", she conducted outreach and education in the museum, brought specimens to local schools, and appeared on The Tonight Show. She began practicing origami first as an extension of her interest in insects, starting a tradition of using origami creatures to decorate the museum's Christmas tree. In the 1960s, she became more involved with the origami community and, in 1978, co-founded the Friends of the Origami Center of America in New York with Lillian Oppenheimer and Michael Shall, now known as OrigamiUSA. (Full article...)
Vernonopterus is a genus of eurypterid, a group of extinct aquatic arthropods. Fossils of Vernonopterus have been discovered in deposits of the Carboniferous period in Scotland. The name of the genus derives from the location where the only known fossil has been discovered, Mount Vernon near Airdrie in Lanarkshire, Scotland. A single species of Vernonopterus is recognized, V. minutisculptus, based on fragmentary fossilized tergites, segments on the upper side of the abdomen. The species name minutisculptus refers to the ornamentation of scales that covers the entirety of the preserved parts of the eurypterid.
Although little can confidently be said about the appearance of Vernonopterus, it is likely to have been similar to its relatives within the hibbertopteridfamily, Hibbertopterus and Campylocephalus. The hibbertopterids were large eurypterids with broad heads and bodies and appendages developed for sweep-feeding, a technique involving blade-like adaptations to search for food in the substrate of its living environment. Compared to both Hibbertopterus and Campylocephalus, Vernonopterus would have been small, reaching lengths of about 50 centimetres (19.7 inches). (Full article...)
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Close up head detail of M. nigrocincta
Myrmecia nigrocincta, commonly known as the jumper ant or jumping jack, is an ant of the genus Myrmecia. The species was first described by Frederick Smith in 1858. Colonies of this ant are abundant in eastern Australia. Ants of this species are known for their ability to jump up to 10 centimetres, and they also have a powerful, venomous sting. Rather than foraging on the ground, M. nigrocincta prefer to forage in trees where they are known to pollinate certain flowers.
This ant is a large species, some workers can grow to over 15mm (0.6in) in length. They have a distinctive pattern of orange-red and black which distinguishes them from other Myrmecia species. M. nigrocincta possess the gamergates gene which allows workers to reproduce, either in the presence of a queen or in a colony where the queen is missing. Life expectancy of a worker ant is over one year. They are aggressive when attacking intruders. (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, Australia, New Zealand, Ireland, and other English speaking territories; "lady" refers to Mary, the mother of Jesus. 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...)
Mole crickets are members of the insect familyGryllotalpidae, in the orderOrthoptera (grasshoppers, locusts, and crickets). Mole crickets are cylindrical-bodied, fossorialinsects about 3–5cm (1.2–2.0in) long as adults, with small eyes and shovel-like fore limbs highly developed for burrowing. They are present in many parts of the world and where they have arrived in new regions, they may become agricultural pests.
Mole crickets have three life stages: eggs, nymphs, and adults. Most of their lives in these stages are spent underground, but adults have wings and disperse in the breeding season. They vary in their diet: some species are herbivores, mainly feeding on roots; others are omnivores, including worms and grubs in their diet; and a few are largely predatory. Male mole crickets have an exceptionally loud song; they sing from a burrow that opens out into the air in the shape of an exponential horn. The song is an almost pure tone, modulated into chirps. It is used to attract females, either for mating, or for indicating favourable habitats for them to lay their eggs.
In Zambia, mole crickets are thought to bring good fortune, while in Latin America, they are said to predict rain. In Florida, where Neoscapteriscus mole crickets are not native, they are considered pests, and various biological controls have been used. Gryllotalpa species have been used as food in West Java, Vietnam, Thailand, Laos, and the Philippines. (Full article...)
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Fossil carapace and portions of the abdomen of R. vaningeni
Rhinocarcinosoma is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of Rhinocarcinosoma have been discovered in deposits ranging of Late Silurian age in the United States, Canada and Vietnam. The genus contains three species, the American R. cicerops and R. vaningeni and the Vietnamese R. dosonensis. The generic name is derived from the related genus Carcinosoma, and the Greek ῥινός (rhinós, "nose"), referring to the unusual shovel-shaped protrusion on the front of the carapace (head plate) of Rhinocarcinosoma, its most distinctive feature.
Other than the protrusion, Rhinocarcinosoma was anatomically very similar to its close relative, Eusarcana, though it lacked the scorpion-like telson (the posteriormost division of the body) of that genus. Further distinguishing features include more slender appendages and slightly different ornamentation of scales. In terms of size, Rhinocarcinosoma was a medium-sized carcinosomatid eurypterid, with the largest species, R. vaningeni, reaching lengths of 39 centimetres (15.4 in).
In contrast to other carcinosomatids, Rhinocarcinosoma is not known only from marine settings, but also from deposits that were once lakes or rivers. It was adapted to a bottom-dwelling lifestyle, as either a burrowing or digging scavenger or top predator, feeding on other invertebrates and small fish. (Full article...)
Damselflies are flying insects of the suborder Zygoptera in the order Odonata. They are similar to dragonflies, which form the 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...)
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, Africa, Europe and Asia, the family possibly having achieved a worldwide distribution, and range in age from the Early 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 (7.2ft) 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 five, possibly six, genera: Carcinosoma, Eusarcana, Rhinocarcinosoma, Cruinnopterus, Tigrisopterus, 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...)
Sawflies are wasp-like insects that are in the suborderSymphyta within the order Hymenoptera. The common name comes from the saw-like appearance of the ovipositor, which females use to cut into the plants where they lay their eggs. The name is associated especially with the Tenthredinoidea, by far the largest superfamily in the suborder, with about 7,000 known species in the entire suborder. There are 8,000 described species in more than 800 genera.
Despite their given taxonomic rank of suborder, Symphyta is a paraphyletic group, consisting of several basal groups within the order Hymenoptera, with each one rooted inside the previous group; the various superfamilies of insects called "sawfly" do form a natural group or clade, but this clade also includes the Apocrita – the ants, bees, and wasps – which are not considered sawflies. The primary distinction between sawflies and the Apocrita is that the adult sawflies (the imago) lack a "wasp waist" or petiole; the segments connecting the abdomen and the thorax smoothly transition between the two (leading to their scientific name). Sawflies first appeared 250million years ago in the Triassic. The oldest superfamily, the Xyeloidea, is still extant today. Over 200million years ago, a lineage of sawflies evolved a parasitoid lifestyle, with carnivorous larvae that ate the eggs or larvae of other insects. Sawflies are distributed globally, though they are more diverse in the northernmost hemispheres.
Some sawflies are Batesian mimics of wasps and bees, and the ovipositor can be mistaken for a stinger. Sawflies vary in length, most measuring 2.5 to 20 millimetres (3⁄32 to 25⁄32in); the largest known sawfly measured 55mm (2+1⁄4in). The great majority of sawflies are herbivorous, though the members of the superfamily Orussoidea are parasitoids. Their predators include birds, small mammals such as shrews, and other insects, such as Dipterans and other Hymenopterans, which themselves may be parasitoids of sawflies. The larvae of some species have anti-predator adaptations such as regurgitating irritating liquid and clustering together for safety in numbers. (Full article...)
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Homarus gammarus, known as the European lobster or common lobster, is a species of clawed lobster from the eastern Atlantic Ocean, Mediterranean Sea and parts of the Black Sea. It is closely related to the American lobster, H.americanus. It may grow to a length of 60cm (24in) and a mass of 6 kilograms (13lb), and bears a conspicuous pair of claws. In life, the lobsters are blue, only becoming "lobster red" on cooking. Mating occurs in the summer, producing eggs which are carried by the females for up to a year before hatching into planktoniclarvae. Homarus gammarus is a source of highly esteemed foodstuff, and is widely caught using lobster pots, mostly around the British Isles. (Full article...)
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Fossils of P. pygmaea. ('a) a carapace, (b) the holotype, nearly complete operculum, (c) metasomal tergites and telson, (d) metastoma and (e) a specimen with complete mesosoma and part of the walking legs.
Parahughmilleria is classified in the family Parahughmilleriidae, in the superfamily Adelophthalmoidea.' The adelophthalmoids were characterised by their small size, their parabolic (approximately U-shaped) carapaces and the presence of epimera (lateral "extensions" of the segment) on the seventh segment, among others. Like its relatives, Parahughmilleria possessed reniform (bean-shaped) eyes and spines on its appendages. The largest species was P. hefteri at 12.5cm (5in), making it a small-sized eurypterid. (Full article...)
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female
Neaetha bulawayoensis is a species of jumping spider in the genusNeaetha that lives in Lesotho, South Africa, Uganda, and Zimbabwe. With a specific name based on the place where its holotype was found, Bulawayo in Zimbabwe, it is one of the most widespread ground-dwelling jumping spiders in central South Africa, found in both forests and in houses. The species is medium-sized, with a carapace that is between 2 and 3 mm in length and an abdomen that is between 2.2 and 3 mm in length, although the female is slightly larger than the male. The spider has a distinctive look from the front, with the male having an unusual black and white pattern on the area below its eyes, its clypeus, while the female clypeus and eye field are covered in white hairs, which give the impression that it has a white face. The spider was originally described in 2000 with the name Pellenes bulawayoensis but was moved to its current genus in 2024. (Full article...)
The following are images from various arthropod-related articles on Wikipedia.
Image 1Life restoration of Megachelicerax, the oldest arthropod known to bear true chelicerae, dating to just over 500 million years ago (from Chelicerata)
Image 4 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 7Body structure of a typical crustacean – krill (from Crustacean)
Image 8The fangs in spiders' chelicerae are so sclerotised as to be greatly hardened and darkened (from Arthropod exoskeleton)
Image 9Formation 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 10Mature 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 15Life restoration of species of Lunataspis a genus of xiphosuran (the broader group which includes horseshoe crabs), dating to the Late Ordovician, around 455-445 million years ago. (from Chelicerata)
Image 18This 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 19In 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 20The 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 21Crab larva barely recognisable as a crab, radically changes its form when it undergoes ecdysis as it matures (from Arthropod exoskeleton)
Image 28Ghost 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 31Life restoration of Sanctacaris (Habeliida), one of the oldest known chelicerate relatives from the mid-Cambrian Burgess Shale, around 508 million years ago. (from Chelicerata)
Image 32Some 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)
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 14mm (0.55in) in diameter.
The head and mandibles of an Australianbull ant. Insect mandibles grasp, crush, or cut the insect’s food, or defend against predators or rivals. These mandibles move in the horizontal plane unlike those of the vertebrates.
A mole cricket, an insect belonging to the Gryllotalpidaefamily. Mole crickets are common insects, found on every continent except Antarctica, but because they are nocturnal and spend nearly all their lives underground in extensive tunnel systems, they are rarely seen. This specimen is likely to be Gryllotalpa brachyptera and is about 3.5cm (1.4in.) in size.
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.
The oriental hornet (Vespa orientalis) is a social insect in the family Vespidae, found in southern Europe, northeastern Africa, and western Asia. This worker, photographed in Sha'ar Poleg Reserve in Israel, is gathering nectar from a sea squill; adults will also feed on honeydew and fruit. They also capture insects such as grasshoppers, flies and honey bees to provide a diet high in protein for the colony's brood.
The red rock crab (Grapsus grapsus) is one of the most common crabs along the western coast of the Americas. Adults are quite variable in color, including brownish-red, mottled or spotted brown, pink, yellow, bright orange and red. It feeds on algae primarily, sometimes sampling other plant matter and dead animals.
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 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.
A fishing spider with two of its legs missing. Most likely some predator (a bird, or given its habitat a large fish or frog) grasped the spider by the missing limbs which were jettisoned by the spider in response, a process known as autotomy.
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 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.
A honey bee extracts nectar from a flower using its proboscis. Tiny hairs covering the bee's body maintain a slight electrostatic charge, causing pollen from the flower's anthers to stick to the bee's hairs, allowing for pollination when the bee moves on to another flower.
The rose chafer (Cetonia aurata) is a reasonably large beetle (20mm/¾in long) that has metallic green coloration with a distinct V shaped scutellum, the small triangular area between the wing cases just below the thorax. Rose chafers are found over southern and central Europe and the southern part of the UK.
A macro shot of the head of a dragonfly, focusing on its compound eyes. Dragonfly eyes have up to 30,000 facets; each one is a separate light-sensing organ or ommatidium, arranged to give nearly a 360° field of vision.
A male Roesel's bush-cricket (Metrioptera roeseli), a European bush-cricket named after August Johann Rösel von Rosenhof, a German entomologist. Its song is very similar to that of Savi's Warbler. Its body length as an adult insect is 15 to 18 mm. It is brown with a pale margin to the sides of the pronotum. Its forewings usually reach midway along its abdomen at rest. However there is a macropterous form of this insect (f. diluta), in which the wings reach beyond the tip of the abdomen. This form appears predominantly during hot summers and enables the species to extend its geographical range rapidly while conditions are suitable; such migrations may also be in response to local overpopulation.
A European paper wasp (Polistes dominula) heating a bubble of regurgitated fluid in the sunlight. This is a common practice among many winged insects, and it is believed to be a way to facilitate digestion or to cool themselves off.
Leptosia nina, known as the psyche, is a species of butterfly in the family Pieridae (the sulphurs, yellows and whites), found in the Indian subcontinent, southeastern Asia, and Australia. It has a small wingspan of 2.5 to 5cm (1 to 2in). The upper side of the otherwise white forewing has a large, somewhat pear-shaped, black spot; this spot is also present on the underside which is scattered with greenish dots and speckles, sometimes arranged in bands. This L.nina butterfly was photographed in Kerala, India.
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.
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