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 mosquito life cycle consists of four stages: egg, larva, pupa, and adult. Eggs are laid on the water surface; they hatch into motile larvae that feed on aquatic algae and organic material. These larvae are important food sources for many freshwater animals, such as dragonfly nymphs, many fish, and some birds. Adult females of many species have mouthparts adapted to pierce the skin of a host and feed on blood of a wide range of vertebrate hosts, and some invertebrates, primarily other arthropods. Some species only produce eggs after a blood meal.
The mosquito's saliva is transferred to the host during the bite, and can cause an itchy rash. In addition, blood-feeding species can ingest pathogens while biting, and transmit them to other hosts. Those species include vectors of parasitic diseases such as malaria and filariasis, and arboviral diseases such as yellow fever and dengue fever. By transmitting diseases, mosquitoes cause the deaths of over 725,000 people each year. (Full article...)
The Phasmatodea (also known as Phasmida or Phasmatoptera) are an order of insects whose members are variously known as stick insects, stick-bugs, walkingsticks, stick animals, or bug sticks. They are also occasionally referred to as Devil's darning needles, although this name is shared by both dragonflies and crane flies. They can be generally referred to as phasmatodeans, phasmids, or ghost insects, with phasmids in the family Phylliidae called leaf insects, leaf-bugs, walking leaves, or bug leaves. The group's name is derived from the Ancient Greekφάσμαphasma, meaning an apparition or phantom, referring to their resemblance to vegetation while in fact being animals. Their natural camouflage makes them difficult for predators to detect; still, many species have one of several secondary lines of defense in the form of startle displays, spines or toxic secretions. Stick insects from the genera Phryganistria, Ctenomorpha, and Phobaeticus include the world's longest insects.
Members of the order are found on all continents except Antarctica, but they are most abundant in the tropics and subtropics. They are herbivorous, with many species living unobtrusively in the tree canopy. They have an incomplete metamorphosis life cycle with three stages: egg, nymph and adult. Many phasmids are parthenogenic, and do not require fertilized eggs for female offspring to be produced. In hotter climates, they may breed all year round; in more temperate regions, the females lay eggs in the autumn before dying, and the new generation hatches in the spring. Some species have wings and can disperse by flying, while others are more restricted. (Full article...)
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C. citricola from Portugal
Cyrtophora citricola, also known as the tropical tent-web spider, is an orb-weaver spider in the family Araneidae. It is found in Asia, Africa, Australia, Costa Rica, Hispaniola, Colombia, and Southern Europe and in 2000, it was discovered in Florida. C. citricola differs from many of its close relatives due its ability to live in a wide variety of environments. In North America and South America, the spider has caused extensive damage to agricultural operations.
C. citricola is in the orb web spider family, but its orb webs are considered atypical. They have a thick silk strand barrier above the orb and a thinner barrier below the orb. This gives the webs a horizontal mesh-like appearance. The spider has developed distinct and specific prey-capturing techniques using its unconventional webs. The prey flies into the upper mesh layer of the web and is deflected into the orb web. The spider then collects and stores the prey in its web. The difference in C. citricola's web silk stems from physiological variations in its spinning apparatuses, as compared to other closely related species. Its webs are non-adhesive and do not require daily respinning.
This spider is one of the few species to exhibit a variable level of sociality. C. citricola can be seen in colonies, which may have arisen due to reduced predation. Within these colonies, each spider has its own web that is linked to other spiders through communal webbing. The spider webs are often built in large matrices next to one another and can span entire trees. The spider usually peacefully coexists with other spiders in the colony. However, at times the spider may have to ward off other spiders in the colony that may try and claim its web. (Full article...)
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Souvenir theatre card
Henry Edwards (27 August 1827 – 9 June 1891) was an English stage actor, writer and entomologist who gained fame in Australia, San Francisco and New York City for his theatre work.
Edwards was drawn to the theatre early in life, and he appeared in amateur productions in London. After sailing to Australia, Edwards appeared professionally in Shakespearean plays and light comedies primarily in Melbourne and Sydney. Throughout his childhood in England and his acting career in Australia, he was greatly interested in collecting insects, and the National Museum of Victoria used the results of his Australian fieldwork as part of the genesis of their collection.
In San Francisco, Edwards was a founding member of the Bohemian Club, and a gathering in Edwards' honour was the spark which began the club's traditional summer encampment at the Bohemian Grove. As well, Edwards cemented his reputation as a preeminent stage actor and theatre manager. After writing a series of influential studies on Pacific Coast butterflies and moths he was elected life member of the California Academy of Sciences. Relocating to the East Coast, Edwards spent a brief time in Boston theatre. This led to a connection to Wallack's Theatre and further renown in New York City. There, Edwards edited three volumes of the journal Papilio and published a major work about the life of the butterfly. His large collection of insect specimens served as the foundation of the American Museum of Natural History's butterfly and moth studies. (Full article...)
Chamberlin was a prolific taxonomist who named over 4,000 new animal species in over 400 scientific publications. He specialized in arachnids (spiders, scorpions, and relatives) and myriapods (centipedes, millipedes, and relatives), ranking among the most prolific arachnologists and myriapodologists in history. He described over 1,400 species of spiders, 1,000 species of millipedes, and the majority of North American centipedes, although the quantity of his output was not always matched with quality, leaving a mixed legacy to his successors. He also did pioneering ethnobiological studies with the Goshute and other indigenous people of the Great Basin, cataloging indigenous names and cultural uses of plants and animals. Chamberlin was celebrated by his colleagues at the University of Utah, however he was disliked among some arachnologists, including some of his former students. After retirement he continued to write, publishing on the history of education in his home state, especially that of the University of Utah.
Chamberlin was a member of the Church of Jesus Christ of Latter-day Saints (LDS Church). In the early twentieth century, Chamberlin was among a quartet of popular Mormon professors at Brigham Young University whose teaching of evolution and biblical criticism resulted in a 1911 controversy among University and Church officials, eventually resulting in the resignation of him and two other professors despite widespread support from the student body, an event described as Mormonism's "first brush with modernism". (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...)
Psylliodes luridipennis, commonly known as the Lundy cabbage flea beetle or the bronze Lundy cabbage flea beetle, is a species of flea beetle endemic to the island of Lundy, where it lives and feeds upon the endemic Lundy cabbage (Coincya wrightii). Along with the true weevilCeutorhynchus contractus var. pallipes and an undescribed race of flea beetle Psylliodes napi, it is known only from the Lundy cabbage. The species was first recorded by Thomas Vernon Wollaston in the 1840s, and was named by the Austrian entomologist Franz Kutschera in 1864.
Adult Lundy cabbage flea beetle measure around 3 millimetres (0.12 in) in length. They have brassy-green heads and bodies, with reddish-brown elytra. The adults feed upon the leaves of the Lundy cabbage, while the larvae mine into the plants to feed. The species is threatened by fluctuating numbers of Lundy cabbages, particularly due to invasive common rhododendrons (Rhododendron ponticum). (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...)
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...)
Mantises are an order (Mantodea) of insects that contains over 2,400 species in about 460 genera in 33 families. The largest family is the Mantidae ("mantids"). Mantises are distributed worldwide in temperate and tropical habitats. They have triangular heads with bulging eyes supported on flexible necks. Their elongated bodies may or may not have wings, but all Mantodea have forelegs that are greatly enlarged and adapted for catching and gripping prey; their upright posture, while remaining stationary with forearms folded, has led to the common name praying mantis.
The closest relatives of mantises are termites and cockroaches (Blattodea), which are all within the superorderDictyoptera. Mantises are sometimes confused with stick insects (Phasmatodea), other elongated insects such as grasshoppers (Orthoptera), or other more distantly related insects with raptorial forelegs such as mantisflies (Mantispidae). Mantises are mostly ambush predators, but a few ground-dwelling species are found actively pursuing their prey. They normally live for about a year. In cooler climates, the adults lay eggs in autumn, then die. The eggs are protected by their hard capsules and hatch in the spring. Females sometimes practice sexual cannibalism, eating their mates after copulation.
The orderEmbioptera, commonly known as webspinners or footspinners, are a small group of mostly tropical and subtropicalinsects, classified under the subclassPterygota. The order has also been called Embiodea or Embiidina. More than 400 species in 11 families have been described, the oldest known fossils of the group being from the mid-Jurassic. Species are very similar in appearance, having long, flexible bodies, short legs, and only males having wings.
Webspinners are gregarious, living subsocially in galleries of fine silk which they spin from glands on their forelegs. Members of these colonies are often related females and their offspring; adult males do not feed and die soon after mating. Males of some species have wings and are able to disperse, whereas the females remain near where they were hatched. Newly mated females may vacate the colony and found a new one nearby. Others may emerge to search for a new food source to which the galleries can be extended, but in general, the insects rarely venture from their galleries. (Full article...)
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Male Trogloraptor marchingtoni
Trogloraptor is a genus of large spiders found in the caves of southwestern Oregon. It is the sole genus in the familyTrogloraptoridae, and includes only one species, Trogloraptor marchingtoni. These spiders are predominantly yellow-brown in color with a maximum leg span of 3 in (7.6 cm). They are remarkable for having hook-like claws on the raptorial last segments of their legs.
Trogloraptor belongs to one of only three new spider families described since 1990. The specific name is in honor of the amateur cave biologist and deputy sheriff Neil Marchington. (Full article...)
The cicadas (/sɪˈkɑːdəz,-ˈkeɪ-/) are a superfamily, the Cicadoidea, of insects in the order Hemiptera (true bugs). They are in the suborder Auchenorrhyncha, along with smaller jumping bugs such as leafhoppers and froghoppers. The superfamily is divided into two families, the Tettigarctidae, with two species in Australia, and the Cicadidae, with more than 3,000 species described from around the world; many species remain undescribed. Nearly all of cicada species are annual cicadas with the exception of the few North American periodical cicada species, genus Magicicada, which in a given region emerge en masse every 13 or 17 years.
Cicadas have prominent eyes set wide apart, short antennae, and membranous front wings. They have an exceptionally loud song, produced in most species by the rapid buckling and unbuckling of drum-like tymbals. The earliest known fossil Cicadomorpha appeared in the Upper Permian period; extant species occur all around the world in temperate to tropical climates. They typically live in trees, feeding on watery sap from xylem tissue, and laying their eggs in a slit in the bark. Most cicadas are cryptic. The vast majority of species are active during the day as adults, with some calling at dawn or dusk. Only a rare few species are known to be nocturnal.
One exclusively North American genus, Magicicada (the periodical cicadas), which spend most of their lives as underground nymphs, emerge in predictable intervals of 13 or 17 years, depending on the species and the location. The unusual duration and synchronization of their emergence may reduce the number of cicadas lost to predation, both by making them a less reliably available prey (so that any predator that evolved to depend on cicadas for sustenance might starve waiting for their emergence), and by emerging in such huge numbers that they will satiate any remaining predators before losing enough of their number to threaten their survival as a species. (Full article...)
... that the "orchid dupe wasp", Lissopimpla excelsa, ejaculates visible amounts of semen as it tries to copulate with flowers of the leafless, large and tartantongue orchids, which it mistakes for a female wasp?
Image 2Ghost 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 3This 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 5Formation 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 6The 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 17Decapods, from Ernst Haeckel's 1904 work Kunstformen der Natur (from Crustacean)
Image 18Body structure of a typical crustacean – krill (from Crustacean)
Image 19Some 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 20 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 21Mature 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 31In 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 32 Honeybee larvae have flexible but delicate unsclerotised cuticles. (from Arthropod exoskeleton)
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 5 cm (1 to 2 in). 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.
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.
Squilla mantis, a species of mantis shrimp, for sale at the fish auction of l'Ametlla de Mar in Catalonia, Spain. It is native to the Mediterranean Sea and adjacent warm parts of the Atlantic Ocean, where it burrows into muddy and sandy seabeds. It is the only native stomatopod to be fished for on a commercial scale in the Mediterranean.
Pieris brassicae, the large white, is a species of butterfly in the family Pieridae, common in Europe, Asia and North Africa. The larva pictured here, which was found at a market in Fronton, France, is a serious pest of plants in the cabbage family, Brassicaceae. The eggs are laid in batches on the undersides of the leaves of plants rich in mustard-oil glucosides, and consumption of these substances as they chew the leaves makes the larvae distasteful; the bright colouration of the larvae signals to predators that they taste bad. Additionally, the adult butterflies emit an unpleasant smell and display warning colours.
A macro view of a Gonia capitatafly feeding on honey, showing its proboscis and pedipalps (the two appendages protruding from the proboscis), two types of insect mouthparts. The proboscis actually comprises the labium, a quadrupedal structure, and a sponge-like labellum at the end. Flies eat solid food by secreting saliva and dabbing it over the food item. As the saliva dissolves the food, the solution is then drawn up into the mouth as a liquid. The labellum's surface is covered by minute food channels which form a tube leading to the esophagus, and food is drawn up the channels by capillary action.
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 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 cryptic mantis (Sibylla pretiosa) is a mantid native to southern Africa. Its common name comes from its ability to grow asymmetrically to match the vegetation of its environment. They have unusual leaf-like projections on the joint of their four walking legs and leaf-like wings, generally the only green portion of the insect's otherwise brown and mottled exoskeleton. Adult females grow to 5–6 cm (2.0–2.4 in) in length while the males are generally about 1 cm smaller.
A compound eye is a visual organ found in certain arthropods. The compound eye consists of between 12 and 1,000 ommatidia, little dark/bright sensors. The image perceived by the arthropod is "recalculated" from the numerous ommatidia which point in slightly different directions. In contrast to other eye types, there is no central lens or retina. Though the resulting image is poor in resolution, it can detect quick movements and, in some cases, the polarization of light.
Dragonflies have about 30,000 facets to their compound eyes, giving them nearly a 360° field of vision.
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.
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.
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.
The longtail tadpole shrimp (Triops longicaudatus) is a freshwater crustacean resembling a miniature horseshoe crab. It is one of the oldest animal species still in existence. Like its relative Triops cancriformis, the longtail tadpole shrimp is considered a living fossil because its basic prehistoric morphology has changed little in the last 70 million years, exactly matching ancient fossils.
Papilio polymnestor, the blue Mormon, is a species of swallowtail butterfly found in southern India and Sri Lanka. It is a woodland species, often seen on forest paths and near streams. The larvae feed on trees in the family Rutaceae, such as citrus. Young larvae are green with white markings and position themselves on the upper surface of leaves, relying on their cryptic colouring, which resembles bird droppings, for protection. Older larvae seek less conspicuous locations, and have a unique habit of securing their balance by weaving silk on the substratum. This adult male P. polymnestor butterfly was photographed in the Indian state of Kerala.
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.
A nest of the tropical Asian giant honey bee, which consists of a single exposed honeycomb, an array of densely packed hexagonal cells made of beeswax. Honeycombs store food (honey and pollen) and house the "brood" (eggs, larvae, and pupae).
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