Portal:Arthropods

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The Arthropods Portal

Arthropods (/ˈɑːrθrəpɒd/) are invertebrates in the phylum Arthropoda. They possess an exoskeleton with a cuticle made of chitin, often mineralised with calcium carbonate, a body with differentiated (metameric) segments, and paired jointed appendages. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. They are an extremely diverse group, with up to 10 million species.

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...)

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  • Image 1 Various centipedes (clockwise from top left): Thereuopoda clunifera, a Scutigeromorph; Lithobius forficatus, a Lithobiomorph; Geophilus, a Geophilomorph; and Scolopendra cataracta, a Scolopendromorph Centipedes (from Neo-Latin centi-, "hundred", and Latin pes, pedis, "foot") are predatory arthropods belonging to the class Chilopoda (Ancient Greek χεῖλος, kheilos, lip, and Neo-Latin suffix -poda, "foot", describing the forcipules) of the subphylum Myriapoda, an arthropod group which includes millipedes and other multi-legged animals. Centipedes are elongated segmented (metameric) creatures with one pair of legs per body segment. All centipedes are venomous and can inflict painful stings, injecting their venom through pincer-like appendages known as forcipules or toxicognaths, which are actually modified legs instead of fangs. Despite the name, no centipede has exactly 100 pairs of legs; the number of pairs of legs is an odd number that ranges from 15 pairs to 191 pairs. Centipedes are predominantly generalist carnivorous, hunting for a variety of prey items that can be overpowered. They have a wide geographical range, which can be found in terrestrial habitats from tropical rainforests to deserts. Within these habitats, centipedes require a moist microhabitat because they lack the waxy cuticle of insects and arachnids, therefore causing them to rapidly lose water. Accordingly, they avoid direct sunlight by staying under cover or by being active at night. (Full article...)

    Various centipedes (clockwise from top left): Thereuopoda clunifera, a Scutigeromorph; Lithobius forficatus, a Lithobiomorph; Geophilus, a Geophilomorph; and Scolopendra cataracta, a Scolopendromorph

    Centipedes (from Neo-Latin centi-, "hundred", and Latin pes, pedis, "foot") are predatory arthropods belonging to the class Chilopoda (Ancient Greek χεῖλος, kheilos, lip, and Neo-Latin suffix -poda, "foot", describing the forcipules) of the subphylum Myriapoda, an arthropod group which includes millipedes and other multi-legged animals. Centipedes are elongated segmented (metameric) creatures with one pair of legs per body segment. All centipedes are venomous and can inflict painful stings, injecting their venom through pincer-like appendages known as forcipules or toxicognaths, which are actually modified legs instead of fangs. Despite the name, no centipede has exactly 100 pairs of legs; the number of pairs of legs is an odd number that ranges from 15 pairs to 191 pairs.

    Centipedes are predominantly generalist carnivorous, hunting for a variety of prey items that can be overpowered. They have a wide geographical range, which can be found in terrestrial habitats from tropical rainforests to deserts. Within these habitats, centipedes require a moist microhabitat because they lack the waxy cuticle of insects and arachnids, therefore causing them to rapidly lose water. Accordingly, they avoid direct sunlight by staying under cover or by being active at night. (Full article...)
  • Image 2 Theridion grallator, also known as the Hawaiian happy-face spider, is a spider in the family Theridiidae that resides on the Hawaiian Islands. T. grallator gets its vernacular name of "Hawaiian happy-face spider" from the unique patterns superimposed on its abdomen, specifically those that resemble a human smiling face. T. grallator is particularly notable because of its wide range of polymorphisms that may be studied to allow a better understanding of evolutionary mechanisms. In addition to the variety of color polymorphisms present, T. grallator demonstrates the interesting quality of diet-induced color change, in which its appearance temporarily changes as it metabolizes various food items. (Full article...)

    Theridion grallator, also known as the Hawaiian happy-face spider, is a spider in the family Theridiidae that resides on the Hawaiian Islands. T. grallator gets its vernacular name of "Hawaiian happy-face spider" from the unique patterns superimposed on its abdomen, specifically those that resemble a human smiling face. T. grallator is particularly notable because of its wide range of polymorphisms that may be studied to allow a better understanding of evolutionary mechanisms. In addition to the variety of color polymorphisms present, T. grallator demonstrates the interesting quality of diet-induced color change, in which its appearance temporarily changes as it metabolizes various food items. (Full article...)
  • Image 3 Worker from Newcastle, New South Wales The green-head ant (Rhytidoponera metallica) is a species of ant that is endemic to Australia. It was described by British entomologist Frederick Smith in 1858 as a member of the genus Rhytidoponera in the subfamily Ectatomminae. These ants measure between 5 and 7 mm (0.20 and 0.28 in). The queens and workers look similar, differing only in size, with the males being the smallest. They are well known for their distinctive metallic appearance, which varies from green to purple or even reddish-violet. Among the most widespread of all insects in Australia, green-head ants are found in almost every Australian state, but are absent in Tasmania. They have also been introduced in New Zealand, where several populations have been established. This species lives in many habitats, including deserts, forests, woodland and urban areas. They nest underground below logs, stones, twigs, and shrubs, or in decayed wooden stumps, and are sometimes found living in termite mounds. They are among the first insects to be found in burnt-off areas after the embers have stopped smouldering. Rain presents no threat to colonies as long as it is a light shower in continuous sunshine. The green-head ant is diurnal, active throughout the day, preying on arthropods and small insects or collecting sweet substances such as honeydew from sap-sucking insects. They play an important role in seed dispersal, scattering and consuming seeds from a variety of species. Predators include the short-beaked echidna (Tachyglossus aculeatus) and a number of bird species. Green-head ant workers are gamergates, meaning they can reproduce with winged males. With workers taking over the reproductive role, queens are relatively insignificant and are rarely produced in colonies. Nuptial flight begins in spring, with males mating with one or two females. Queens that establish their own colonies are semi-claustral, going out and foraging to support their young. Another way colonies are formed is through budding, where a subset of the colony leaves the main colony for an alternative nest site. The green-head ant is known for its painful and venomous sting that can cause anaphylactic shock in sensitive humans. However, they can also be beneficial to humans, acting as a form of pest control by preying on agricultural pests such as beetles, moths and termites. (Full article...)

    Worker from Newcastle, New South Wales

    The green-head ant (Rhytidoponera metallica) is a species of ant that is endemic to Australia. It was described by British entomologist Frederick Smith in 1858 as a member of the genus Rhytidoponera in the subfamily Ectatomminae. These ants measure between 5 and 7 mm (0.20 and 0.28 in). The queens and workers look similar, differing only in size, with the males being the smallest. They are well known for their distinctive metallic appearance, which varies from green to purple or even reddish-violet. Among the most widespread of all insects in Australia, green-head ants are found in almost every Australian state, but are absent in Tasmania. They have also been introduced in New Zealand, where several populations have been established.

    This species lives in many habitats, including deserts, forests, woodland and urban areas. They nest underground below logs, stones, twigs, and shrubs, or in decayed wooden stumps, and are sometimes found living in termite mounds. They are among the first insects to be found in burnt-off areas after the embers have stopped smouldering. Rain presents no threat to colonies as long as it is a light shower in continuous sunshine. The green-head ant is diurnal, active throughout the day, preying on arthropods and small insects or collecting sweet substances such as honeydew from sap-sucking insects. They play an important role in seed dispersal, scattering and consuming seeds from a variety of species. Predators include the short-beaked echidna (Tachyglossus aculeatus) and a number of bird species.

    Green-head ant workers are gamergates, meaning they can reproduce with winged males. With workers taking over the reproductive role, queens are relatively insignificant and are rarely produced in colonies. Nuptial flight begins in spring, with males mating with one or two females. Queens that establish their own colonies are semi-claustral, going out and foraging to support their young. Another way colonies are formed is through budding, where a subset of the colony leaves the main colony for an alternative nest site. The green-head ant is known for its painful and venomous sting that can cause anaphylactic shock in sensitive humans. However, they can also be beneficial to humans, acting as a form of pest control by preying on agricultural pests such as beetles, moths and termites. (Full article...)
  • Image 4 Male M. campanulae Megachile campanulae, known as the bellflower resin bee, is a species of bee in the family Megachilidae. Described in 1903, these solitary bees are native to eastern North America. Studies in 2013 placed them among the first insect species to use synthetic materials for making nests. They are considered mason bees, which is a common descriptor of bees in several families, including Megachilidae. Within the genus Megachile, frequently also referred to as leafcutter bees, M. campanulae is a member of the subgenus Chelostomoides, which do not construct nests from cut leaves, but rather from plant resins and other materials. Females lay eggs in nests constructed with individual cell compartments for each egg. Once hatched, the eggs progress through larval stages and subsequently will overwinter as pupae. The bees are susceptible to parasitism from several other bee species, which act as brood parasites. They are medium-sized bees and the female adults are typically larger than the males. They are important pollinators of numerous native plant species throughout their range. (Full article...)

    Male M. campanulae

    Megachile campanulae, known as the bellflower resin bee, is a species of bee in the family Megachilidae. Described in 1903, these solitary bees are native to eastern North America. Studies in 2013 placed them among the first insect species to use synthetic materials for making nests. They are considered mason bees, which is a common descriptor of bees in several families, including Megachilidae. Within the genus Megachile, frequently also referred to as leafcutter bees, M. campanulae is a member of the subgenus Chelostomoides, which do not construct nests from cut leaves, but rather from plant resins and other materials. Females lay eggs in nests constructed with individual cell compartments for each egg. Once hatched, the eggs progress through larval stages and subsequently will overwinter as pupae. The bees are susceptible to parasitism from several other bee species, which act as brood parasites. They are medium-sized bees and the female adults are typically larger than the males. They are important pollinators of numerous native plant species throughout their range. (Full article...)
  • Image 5 The "Spanish fly", Lytta vesicatoria, has been considered to have medicinal, aphrodisiac, and other properties. Human interactions with insects include both a wide variety of uses, whether practical such as for food, textiles, and dyestuffs, or symbolic, as in art, music, and literature, and negative interactions including damage to crops and extensive efforts to control insect pests. Academically, the interaction of insects and society has been treated in part as cultural entomology, dealing mostly with "advanced" societies, and in part as ethnoentomology, dealing mostly with "primitive" societies, though the distinction is weak and not based on theory. Both academic disciplines explore the parallels, connections and influence of insects on human populations, and vice versa. They are rooted in anthropology and natural history, as well as entomology, the study of insects. Other cultural uses of insects, such as biomimicry, do not necessarily lie within these academic disciplines. More generally, people make a wide range of uses of insects, both practical and symbolic. On the other hand, attitudes to insects are often negative, and extensive efforts are made to kill them. The widespread use of insecticides has failed to exterminate any insect pest, but has caused resistance to commonly-used chemicals in a thousand insect species. (Full article...)
    The "Spanish fly", Lytta vesicatoria, has been considered to have medicinal, aphrodisiac, and other properties.

    Human interactions with insects include both a wide variety of uses, whether practical such as for food, textiles, and dyestuffs, or symbolic, as in art, music, and literature, and negative interactions including damage to crops and extensive efforts to control insect pests.

    Academically, the interaction of insects and society has been treated in part as cultural entomology, dealing mostly with "advanced" societies, and in part as ethnoentomology, dealing mostly with "primitive" societies, though the distinction is weak and not based on theory. Both academic disciplines explore the parallels, connections and influence of insects on human populations, and vice versa. They are rooted in anthropology and natural history, as well as entomology, the study of insects. Other cultural uses of insects, such as biomimicry, do not necessarily lie within these academic disciplines.

    More generally, people make a wide range of uses of insects, both practical and symbolic. On the other hand, attitudes to insects are often negative, and extensive efforts are made to kill them. The widespread use of insecticides has failed to exterminate any insect pest, but has caused resistance to commonly-used chemicals in a thousand insect species. (Full article...)
  • Image 6 A spider of the genus Afraflacilla Afraflacilla braunsi is a species of jumping spider in the genus Afraflacilla. First found in South Africa, the spider was subsequently observed living in Saudi Arabia, Turkmenistan, the United Arab Emirates and Yemen, although it is likely to have a wider distribution. First described in 1903 by George and Elizabeth Peckham, it was originally allocated to the genus Pseudicius with the name Pseudicius braunsii. After being renamed Icius braunsi in 1987, it was finally given its current name by Jerzy Prószyński in 2017. Pseudicius tripunctatus, now called Afraflacilla tripunctatus, is a synonym. A small to medium-sized spider, Afraflacilla braunsi has a carapace that is between 1.7 and 1.9 mm (0.07 and 0.07 in) long and an abdomen 2.2 and 3.2 mm (0.09 and 0.13 in) long. The carapace is brown, sometimes with yellow sides. The abdomen is light brown or fawn with lighter yellow patches. It has large brown front legs, the remainder generally yellow and less robust. It makes noises by rubbing its forelegs against small hairs under its eyes. The copulatory organs are distinctive for the species. The male has a characteristically bulbous palpal bulb and a single long projection, or apophysis, extending from the palpal tibia. The female has very long and coiled insemination ducts that lead to large spermathecae. (Full article...)

    A spider of the genus Afraflacilla

    Afraflacilla braunsi is a species of jumping spider in the genus Afraflacilla. First found in South Africa, the spider was subsequently observed living in Saudi Arabia, Turkmenistan, the United Arab Emirates and Yemen, although it is likely to have a wider distribution. First described in 1903 by George and Elizabeth Peckham, it was originally allocated to the genus Pseudicius with the name Pseudicius braunsii. After being renamed Icius braunsi in 1987, it was finally given its current name by Jerzy Prószyński in 2017. Pseudicius tripunctatus, now called Afraflacilla tripunctatus, is a synonym.

    A small to medium-sized spider, Afraflacilla braunsi has a carapace that is between 1.7 and 1.9 mm (0.07 and 0.07 in) long and an abdomen 2.2 and 3.2 mm (0.09 and 0.13 in) long. The carapace is brown, sometimes with yellow sides. The abdomen is light brown or fawn with lighter yellow patches. It has large brown front legs, the remainder generally yellow and less robust. It makes noises by rubbing its forelegs against small hairs under its eyes. The copulatory organs are distinctive for the species. The male has a characteristically bulbous palpal bulb and a single long projection, or apophysis, extending from the palpal tibia. The female has very long and coiled insemination ducts that lead to large spermathecae. (Full article...)
  • Image 7 Ammophila sabulosa taking nectar on a hemp agrimony flower head Ammophila sabulosa, the red-banded sand wasp, is a species of the subfamily Ammophilinae of the solitary hunting wasp family Sphecidae, also called digger wasps. Found across Eurasia, the parasitoid wasp is notable for the mass provisioning behaviour of the females, hunting caterpillars mainly on sunny days, paralysing them with a sting, and burying them in a burrow with a single egg. The species is also remarkable for the extent to which females parasitise their own species, either stealing prey from nests of other females to provision their own nests, or in brood parasitism, removing the other female's egg and laying one of her own instead. (Full article...)

    Ammophila sabulosa taking nectar on a hemp agrimony flower head

    Ammophila sabulosa, the red-banded sand wasp, is a species of the subfamily Ammophilinae of the solitary hunting wasp family Sphecidae, also called digger wasps. Found across Eurasia, the parasitoid wasp is notable for the mass provisioning behaviour of the females, hunting caterpillars mainly on sunny days, paralysing them with a sting, and burying them in a burrow with a single egg. The species is also remarkable for the extent to which females parasitise their own species, either stealing prey from nests of other females to provision their own nests, or in brood parasitism, removing the other female's egg and laying one of her own instead. (Full article...)
  • Image 8 Restoration of B. taimyrensis Borchgrevinkium is an extinct genus of chelicerate arthropod. A fossil of the single and type species, B. taimyrensis, has been discovered in deposits of the Early Devonian period (Lochkovian epoch) in the Krasnoyarsk Krai, Siberia, Russia. The name of the genus honors Carsten Borchgrevink, an Anglo-Norwegian explorer who participated in many expeditions to Antarctica. Borchgrevinkium represents a poorly known genus whose affinities are uncertain. It had several unique characteristics that differentiated it from many other arthropods, such as its long parabolic (nearly U-shaped) prosoma (head), its elongated first and second segments and the presence of paired "ridges" in the surface of its third to tenth tergites (dorsal halves of the segments). Furthermore, the opisthosoma (the "trunk") of Borchgrevinkium was triangular, and its telson (the posteriormost division of its body), short and wedge-shaped. It was a small animal, approximately 3 centimetres (1.2 inches) long. The only known specimen of the genus was collected in 1956 and described in 1959 by the Russian paleontologist Nestor Ivanovich Novojilov. He determined that it was a eurypterid and classified it in the family Mycteroptidae. However, its classification changed repeatedly over the years, being transferred from Eurypterida to Xiphosura and back to Eurypterida some time later. Borchgrevinkium is tentatively considered as a prosomapod, with more fossil material needed to ensure its current classification. (Full article...)

    Restoration of B. taimyrensis

    Borchgrevinkium is an extinct genus of chelicerate arthropod. A fossil of the single and type species, B. taimyrensis, has been discovered in deposits of the Early Devonian period (Lochkovian epoch) in the Krasnoyarsk Krai, Siberia, Russia. The name of the genus honors Carsten Borchgrevink, an Anglo-Norwegian explorer who participated in many expeditions to Antarctica. Borchgrevinkium represents a poorly known genus whose affinities are uncertain.

    It had several unique characteristics that differentiated it from many other arthropods, such as its long parabolic (nearly U-shaped) prosoma (head), its elongated first and second segments and the presence of paired "ridges" in the surface of its third to tenth tergites (dorsal halves of the segments). Furthermore, the opisthosoma (the "trunk") of Borchgrevinkium was triangular, and its telson (the posteriormost division of its body), short and wedge-shaped. It was a small animal, approximately 3 centimetres (1.2 inches) long.

    The only known specimen of the genus was collected in 1956 and described in 1959 by the Russian paleontologist Nestor Ivanovich Novojilov. He determined that it was a eurypterid and classified it in the family Mycteroptidae. However, its classification changed repeatedly over the years, being transferred from Eurypterida to Xiphosura and back to Eurypterida some time later. Borchgrevinkium is tentatively considered as a prosomapod, with more fossil material needed to ensure its current classification. (Full article...)
  • Image 9 Portia schultzi is a species of jumping spider which ranges from South Africa in the south to Kenya in the north, and also is found in West Africa and Madagascar. In this species, which is slightly smaller than some other species of the genus Portia, the bodies of females are 5 to 7 mm (0.20 to 0.28 in) long, while those of males are 4 to 6 mm (0.16 to 0.24 in) long. The carapaces of both sexes are orange-brown with dark brown mottling, and covered with dark brown and whitish hairs lying over the surface. Males have white tufts on their thoraces and a broad white band above the bases of the legs, and these features are less conspicuous in females. Both sexes have tufts of orange to dark orange above the eyes, which are fringed with pale orange hairs. Males' abdomens are yellow-orange to orange-brown with blackish mottling, and on the upper sides are black and light orange hairs, and nine white tufts. Those of females are pale yellow and have black markings with scattered white and orange-brown hairs on the upper side. P. schultzi has relatively longer legs than other Portia, and a "lolloping" gait. While most jumping spiders focus accurately up to about 75 cm (30 in) away, P. schultzi responds to a maximum of about 10 cm (3.9 in) in good light, and ignores everything in very subdued light. For prey, P. schultzi prefers web-based spiders, then jumping spiders, and finally insects. The females of P. schultzi and other Portia species build "capture webs" to catch prey, and often join their own webs on to web-based spiders to catch the other spiders or their prey. If a P. schultzi female is mature, a male P. schultzi will try to copulate with her, or cohabit with a subadult female and copulate while she is moulting. They usually mate on a web or on a dragline made by the female, and P. schultzi typically copulates for about 100 seconds, while others in the genus can take several minutes or even several hours. Females try to kill and eat their mates during or after copulation, and subadult females mimic adult females to attract males as prey. Contests between Portia females are violent, and embraces in P. schultzi typically take 20 to 60 seconds. Sometimes, one female knocks the other on her back and the other may be killed and eaten if she does not right herself quickly and run away. When hunting, P. schultzi mature females emit olfactory signals that reduce the risk that any other females, males, or juveniles of the same species may contend for the same prey. (Full article...)

    Portia schultzi is a species of jumping spider which ranges from South Africa in the south to Kenya in the north, and also is found in West Africa and Madagascar. In this species, which is slightly smaller than some other species of the genus Portia, the bodies of females are 5 to 7 mm (0.20 to 0.28 in) long, while those of males are 4 to 6 mm (0.16 to 0.24 in) long. The carapaces of both sexes are orange-brown with dark brown mottling, and covered with dark brown and whitish hairs lying over the surface. Males have white tufts on their thoraces and a broad white band above the bases of the legs, and these features are less conspicuous in females. Both sexes have tufts of orange to dark orange above the eyes, which are fringed with pale orange hairs. Males' abdomens are yellow-orange to orange-brown with blackish mottling, and on the upper sides are black and light orange hairs, and nine white tufts. Those of females are pale yellow and have black markings with scattered white and orange-brown hairs on the upper side. P. schultzi has relatively longer legs than other Portia, and a "lolloping" gait.

    While most jumping spiders focus accurately up to about 75 cm (30 in) away, P. schultzi responds to a maximum of about 10 cm (3.9 in) in good light, and ignores everything in very subdued light. For prey, P. schultzi prefers web-based spiders, then jumping spiders, and finally insects. The females of P. schultzi and other Portia species build "capture webs" to catch prey, and often join their own webs on to web-based spiders to catch the other spiders or their prey.

    If a P. schultzi female is mature, a male P. schultzi will try to copulate with her, or cohabit with a subadult female and copulate while she is moulting. They usually mate on a web or on a dragline made by the female, and P. schultzi typically copulates for about 100 seconds, while others in the genus can take several minutes or even several hours. Females try to kill and eat their mates during or after copulation, and subadult females mimic adult females to attract males as prey. Contests between Portia females are violent, and embraces in P. schultzi typically take 20 to 60 seconds. Sometimes, one female knocks the other on her back and the other may be killed and eaten if she does not right herself quickly and run away. When hunting, P. schultzi mature females emit olfactory signals that reduce the risk that any other females, males, or juveniles of the same species may contend for the same prey. (Full article...)
  • Image 10 The deathwatch beetle (Xestobium rufovillosum) is a species of woodboring beetle that sometimes infests the structural timbers of old buildings. The adult beetle is brown and measures on average 7 mm (0.3 in) long. Eggs are laid in dark crevices in old wood inside buildings, trees, and inside tunnels left behind by previous larvae. The larvae bore into the timber, feeding for up to ten years before pupating, and later emerging from the wood as adult beetles. Timber that has been damp and is affected by fungal decay is soft enough for the larvae to chew through. They obtain nourishment by using enzymes present in their gut to digest the cellulose and hemicellulose in the wood. The larvae of deathwatch beetles weaken the structural timbers of a building by tunneling through them. Treatment with insecticides to kill the larvae is largely ineffective, and killing the adult beetles when they emerge in spring and early summer may be a better option. However, infestation by these beetles is often limited to historic buildings, because modern buildings tend to use softwoods for joists and rafters instead of aged oak timbers, which the beetles prefer. To attract mates, the adult insects create a tapping or ticking sound that can sometimes be heard in the rafters of old buildings on summer nights; therefore, the deathwatch beetle is associated with quiet, sleepless nights and is named for the vigil (watch) being kept beside the dying or dead. By extension, there exists a superstition that these sounds are an omen of impending death. (Full article...)

    The deathwatch beetle (Xestobium rufovillosum) is a species of woodboring beetle that sometimes infests the structural timbers of old buildings. The adult beetle is brown and measures on average 7 mm (0.3 in) long. Eggs are laid in dark crevices in old wood inside buildings, trees, and inside tunnels left behind by previous larvae. The larvae bore into the timber, feeding for up to ten years before pupating, and later emerging from the wood as adult beetles. Timber that has been damp and is affected by fungal decay is soft enough for the larvae to chew through. They obtain nourishment by using enzymes present in their gut to digest the cellulose and hemicellulose in the wood.

    The larvae of deathwatch beetles weaken the structural timbers of a building by tunneling through them. Treatment with insecticides to kill the larvae is largely ineffective, and killing the adult beetles when they emerge in spring and early summer may be a better option. However, infestation by these beetles is often limited to historic buildings, because modern buildings tend to use softwoods for joists and rafters instead of aged oak timbers, which the beetles prefer.

    To attract mates, the adult insects create a tapping or ticking sound that can sometimes be heard in the rafters of old buildings on summer nights; therefore, the deathwatch beetle is associated with quiet, sleepless nights and is named for the vigil (watch) being kept beside the dying or dead. By extension, there exists a superstition that these sounds are an omen of impending death. (Full article...)
  • Image 11 Arthropods (/ˈɑːrθrəpɒd/) are invertebrates in the phylum Arthropoda. They possess an exoskeleton with a cuticle made of chitin, often mineralised with calcium carbonate, a body with differentiated (metameric) segments, and paired jointed appendages. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. They are an extremely diverse group, with up to 10 million species. Haemolymph is the analogue of blood for most arthropods. An arthropod has an open circulatory system, with a body cavity called a haemocoel through which haemolymph circulates to the interior organs. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. Their nervous system is "ladder-like", with paired ventral nerve cords running through all segments and forming paired ganglia in each segment. Their heads are formed by fusion of varying numbers of segments, and their brains are formed by fusion of the ganglia of these segments and encircle the esophagus. The respiratory and excretory systems of arthropods vary, depending as much on their environment as on the subphylum to which they belong. Arthropods use combinations of compound eyes and pigment-pit ocelli for vision. In most species, the ocelli can only detect the direction from which light is coming, and the compound eyes are the main source of information, but the main eyes of spiders are ocelli that can form images and, in a few cases, can swivel to track prey. Arthropods also have a wide range of chemical and mechanical sensors, mostly based on modifications of the many bristles known as setae that project through their cuticles. Similarly, their reproduction and development are varied; all terrestrial species use internal fertilization, but this is sometimes by indirect transfer of the sperm via an appendage or the ground, rather than by direct injection. Aquatic species use either internal or external fertilization. Almost all arthropods lay eggs, with many species giving birth to live young after the eggs have hatched inside the mother; but a few are genuinely viviparous, such as aphids. Arthropod hatchlings vary from miniature adults to grubs and caterpillars that lack jointed limbs and eventually undergo a total metamorphosis to produce the adult form. The level of maternal care for hatchlings varies from nonexistent to the prolonged care provided by social insects. (Full article...)

    Arthropods (/ˈɑːrθrəpɒd/) are invertebrates in the phylum Arthropoda. They possess an exoskeleton with a cuticle made of chitin, often mineralised with calcium carbonate, a body with differentiated (metameric) segments, and paired jointed appendages. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. They are an extremely diverse group, with up to 10 million species.

    Haemolymph is the analogue of blood for most arthropods. An arthropod has an open circulatory system, with a body cavity called a haemocoel through which haemolymph circulates to the interior organs. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. Their nervous system is "ladder-like", with paired ventral nerve cords running through all segments and forming paired ganglia in each segment. Their heads are formed by fusion of varying numbers of segments, and their brains are formed by fusion of the ganglia of these segments and encircle the esophagus. The respiratory and excretory systems of arthropods vary, depending as much on their environment as on the subphylum to which they belong.

    Arthropods use combinations of compound eyes and pigment-pit ocelli for vision. In most species, the ocelli can only detect the direction from which light is coming, and the compound eyes are the main source of information, but the main eyes of spiders are ocelli that can form images and, in a few cases, can swivel to track prey. Arthropods also have a wide range of chemical and mechanical sensors, mostly based on modifications of the many bristles known as setae that project through their cuticles. Similarly, their reproduction and development are varied; all terrestrial species use internal fertilization, but this is sometimes by indirect transfer of the sperm via an appendage or the ground, rather than by direct injection. Aquatic species use either internal or external fertilization. Almost all arthropods lay eggs, with many species giving birth to live young after the eggs have hatched inside the mother; but a few are genuinely viviparous, such as aphids. Arthropod hatchlings vary from miniature adults to grubs and caterpillars that lack jointed limbs and eventually undergo a total metamorphosis to produce the adult form. The level of maternal care for hatchlings varies from nonexistent to the prolonged care provided by social insects. (Full article...)
  • Image 12 Malacostraca (from Neo-Latin; from Ancient Greek μαλακός (malakós) 'soft', and όστρακον (óstrakon) 'shell') is the second largest of the six classes of pancrustaceans just behind hexapods, containing about 40,000 living species, divided among 16 orders. Its members, the malacostracans, display a great diversity of body forms and include crabs, lobsters, crayfish, shrimp, krill, prawns, woodlice, amphipods, mantis shrimp, tongue-eating lice and many other less familiar animals. They are abundant in all marine environments and have colonised freshwater and terrestrial habitats. They are segmented animals, united by a common body plan comprising 20 body segments (rarely 21), and divided into a head, thorax, and abdomen. (Full article...)

    Malacostraca (from Neo-Latin; from Ancient Greek μαλακός (malakós) 'soft', and όστρακον (óstrakon) 'shell') is the second largest of the six classes of pancrustaceans just behind hexapods, containing about 40,000 living species, divided among 16 orders. Its members, the malacostracans, display a great diversity of body forms and include crabs, lobsters, crayfish, shrimp, krill, prawns, woodlice, amphipods, mantis shrimp, tongue-eating lice and many other less familiar animals. They are abundant in all marine environments and have colonised freshwater and terrestrial habitats. They are segmented animals, united by a common body plan comprising 20 body segments (rarely 21), and divided into a head, thorax, and abdomen. (Full article...)
  • Image 13 Artist's image Hemigrapsus estellinensis is an extinct species of crab, formerly endemic to the Texas Panhandle. It was discovered by Gordon C. Creel in 1962 and was probably already extinct before his description was published in 1964, after the Estelline Salt Springs where it lived were contained by the United States Army Corps of Engineers. H. estellinensis is closely related to species from the Pacific Ocean such as Hemigrapsus oregonensis, but lived 800 km (500 mi) inland in a hypersaline spring. It differed from its relatives by the pattern of spots on its back, and by the relative sizes of its limbs. (Full article...)

    Artist's image

    Hemigrapsus estellinensis is an extinct species of crab, formerly endemic to the Texas Panhandle. It was discovered by Gordon C. Creel in 1962 and was probably already extinct before his description was published in 1964, after the Estelline Salt Springs where it lived were contained by the United States Army Corps of Engineers. H. estellinensis is closely related to species from the Pacific Ocean such as Hemigrapsus oregonensis, but lived 800 km (500 mi) inland in a hypersaline spring. It differed from its relatives by the pattern of spots on its back, and by the relative sizes of its limbs. (Full article...)
  • Image 14 Red-tailed bumblebee (Bombus lapidarius) A bumblebee (or bumble bee, bumble-bee, or humble-bee) is any of over 250 species in the genus Bombus, part of Apidae, one of the bee families. This genus is the only extant group in the tribe Bombini, though a few extinct related genera (e.g., Calyptapis) are known from fossils. They are found primarily in higher altitudes or latitudes in the Northern Hemisphere, although they are also found in South America, where a few lowland tropical species have been identified. European bumblebees have also been introduced to New Zealand and Tasmania. Female bumblebees can sting repeatedly, but generally ignore humans and other animals. Most bumblebees are social insects that form colonies with a single queen. The colonies are smaller than those of honey bees, growing to as few as 50 individuals in a nest. Cuckoo bumblebees are brood parasitic and do not make nests or form colonies; their queens aggressively invade the nests of other bumblebee species, kill the resident queens and then lay their own eggs, which are cared for by the resident workers. Cuckoo bumblebees were previously classified as a separate genus, but are now usually treated as members of Bombus. Bumblebees have round bodies covered in soft hair (long branched setae) called 'pile', making them appear and feel fuzzy. They have aposematic (warning) coloration, often consisting of contrasting bands of colour, and different species of bumblebee in a region often resemble each other in mutually protective Müllerian mimicry. Harmless insects such as hoverflies often derive protection from resembling bumblebees, in Batesian mimicry, and may be confused with them. Nest-making bumblebees can be distinguished from similarly large, fuzzy cuckoo bumblebees by the form of the female hind leg. In nesting bumblebees, it is modified to form a pollen basket, a bare shiny area surrounded by a fringe of hairs used to transport pollen, whereas in cuckoo bumblebees, the hind leg is hairy all round, and they never carry pollen. (Full article...)

    Red-tailed bumblebee (Bombus lapidarius)

    A bumblebee (or bumble bee, bumble-bee, or humble-bee) is any of over 250 species in the genus Bombus, part of Apidae, one of the bee families. This genus is the only extant group in the tribe Bombini, though a few extinct related genera (e.g., Calyptapis) are known from fossils. They are found primarily in higher altitudes or latitudes in the Northern Hemisphere, although they are also found in South America, where a few lowland tropical species have been identified. European bumblebees have also been introduced to New Zealand and Tasmania. Female bumblebees can sting repeatedly, but generally ignore humans and other animals.

    Most bumblebees are social insects that form colonies with a single queen. The colonies are smaller than those of honey bees, growing to as few as 50 individuals in a nest. Cuckoo bumblebees are brood parasitic and do not make nests or form colonies; their queens aggressively invade the nests of other bumblebee species, kill the resident queens and then lay their own eggs, which are cared for by the resident workers. Cuckoo bumblebees were previously classified as a separate genus, but are now usually treated as members of Bombus.

    Bumblebees have round bodies covered in soft hair (long branched setae) called 'pile', making them appear and feel fuzzy. They have aposematic (warning) coloration, often consisting of contrasting bands of colour, and different species of bumblebee in a region often resemble each other in mutually protective Müllerian mimicry. Harmless insects such as hoverflies often derive protection from resembling bumblebees, in Batesian mimicry, and may be confused with them. Nest-making bumblebees can be distinguished from similarly large, fuzzy cuckoo bumblebees by the form of the female hind leg. In nesting bumblebees, it is modified to form a pollen basket, a bare shiny area surrounded by a fringe of hairs used to transport pollen, whereas in cuckoo bumblebees, the hind leg is hairy all round, and they never carry pollen. (Full article...)
  • Image 15 Calliphora vomitoria, known as the blue bottle fly, orange-bearded blue bottle, or bottlebee, is a species of blow fly, a species in the family Calliphoridae. Calliphora vomitoria is the type species of the genus Calliphora. It is common throughout many continents including Europe, Americas, and Africa. They are fairly large flies, nearly twice the size of the housefly, with a metallic blue abdomen and long orange setae on the gena. While adult flies feed on nectar, females deposit their eggs on rotting corpses, making them important forensic insects, as their eggs and timing of oviposition can be used to estimate time of death. (Full article...)

    Calliphora vomitoria, known as the blue bottle fly, orange-bearded blue bottle, or bottlebee, is a species of blow fly, a species in the family Calliphoridae. Calliphora vomitoria is the type species of the genus Calliphora. It is common throughout many continents including Europe, Americas, and Africa. They are fairly large flies, nearly twice the size of the housefly, with a metallic blue abdomen and long orange setae on the gena.

    While adult flies feed on nectar, females deposit their eggs on rotting corpses, making them important forensic insects, as their eggs and timing of oviposition can be used to estimate time of death. (Full article...)

Did you know ... ?

A tiny light brown insect with feathery wings; its body is around 0.4 mm long.
Arescon (Insecta: Hymenoptera: Mymaridae)

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