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Pterostigma
The pterostigma (plural: pterostigmata) is a group of specialized cells in the outer wings of insects, which are often thickened or coloured, and thus stand out from other cells. It is particularly noticeable in dragonflies, but present also in other insect groups, such as snakeflies, hymenopterans, and megalopterans. It is also often referred to as a stigma. Purpose The pterostigma, a heavier section of the wing than nearby sections, assists in gliding. Without the pterostigmata, self-exciting vibrations known as flutter would set in on the wing above a certain critical speed, making gliding impossible. Tests show that with the pterostigmata, the critical gliding speed is increased 10–25% on one species of dragonfly. Pseudopterostigma Some female damselflies in the family Calopterygidae Calopterygidae is a Family (biology), family of damselfly, damselflies, in the suborder Zygoptera. They are commonly known as the broad-winged damselflies, demoiselles, or jewelwings. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snakefly
Snakeflies are a group of predatory insects comprising the order Raphidioptera with two extant families: Raphidiidae and Inocelliidae, consisting of roughly 260 species. In the past, the group had a much wider distribution than it does now; snakeflies are found in temperate regions worldwide but are absent from the tropics and the Southern Hemisphere. Recognizable representatives of the group first appeared during the Early Jurassic. They are a relict group, having reached their apex of diversity during the Cretaceous before undergoing substantial decline. An adult snakefly resembles a lacewing in appearance but has a notably elongated thorax which, together with the mobile head, gives the group their common name. The body is long and slender and the two pairs of long, membranous wings are prominently veined. Females have a large and sturdy ovipositor which is used to deposit eggs in some concealed location. They are holometabolous insects with a four-stage life cycle consisti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insect Wing
Insect wings are adult outgrowths of the insect exoskeleton that enable insect flight, insects to fly. They are found on the second and third Thorax (insect anatomy), thoracic segments (the mesothorax and metathorax), and the two pairs are often referred to as the forewings and hindwings, respectively, though a few insects lack hindwings, even rudiments. The wings are strengthened by a number of longitudinal veins, which often have cross-connections that form closed "cells" in the membrane (extreme examples include the Odonata, dragonflies and Neuroptera, lacewings). The patterns resulting from the fusion and cross-connection of the wing veins are often diagnostic for different evolutionary lineages and can be used for identification to the family (biology), family or even genus level in many order (biology), orders of insects. Physically, some insects move their flight muscles directly, others indirectly. In insects with direct flight, the wing muscles directly attach to the win ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dragonfly
A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of dragonflies are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threatens dragonfly populations around the world. Adult dragonflies are characterised by a pair of large, multifaceted, compound eyes, two pairs of strong, transparent wings, sometimes with coloured patches, and an elongated body. Many dragonflies have brilliant iridescent or metallic colours produced by structural coloration, making them conspicuous in flight. An adult dragonfly's compound eyes have nearly 24,000 ommatidia each. Dragonflies can be mistaken for the closely related damselflies, which make up the other odonatan infraorder ( Zygoptera) and are similar in body plan, though usually lighter in build; however, the wings of most dragonflies are held flat and away from the body, while damselflies hold their wings folded at rest, al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Damselfly
Damselflies are flying insects of the suborder Zygoptera in the order Odonata. They are similar to dragonflies (which constitute the other odonatan suborder, Epiprocta) 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 fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calopterygidae
Calopterygidae is a Family (biology), family of damselfly, damselflies, in the suborder Zygoptera. They are commonly known as the broad-winged damselflies, demoiselles, or jewelwings. These rather large damselflies have wingspans of 50–80 mm (compared to about 44 mm in the common bluetail damselfly, ''Ischnura elegans''), are often metallic-coloured, and can be differentiated from other damselflies by the broader connection between the wings and the body, as opposed to the abrupt narrowing seen in other damselfly families. The family contains some 150 species. The Calopterygidae are found on every continent except Antarctica. They live along rivers and streams.Córdoba-Aguilar, A. & Cordero-Rivera, A. (2005)Evolution and ecology of Calopterygidae (Zygoptera: Odonata): status of knowledge and research perspectives.''Neotrop. Entomol'' 34(6), 861-879. Etymology The name is derived from Greek ''kalos'' meaning beautiful and ''ptery'' meaning winged. Characteristics The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raphidia Ophiopsis M NL-Doorwerth-19540617 Right Wing - Collection Naturalis
''Raphidia'' is a genus of snakefly, mainly found in Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east .... Species The following are included in ''BioLib.cz'': ;subgenus ''Aserbeidshanoraphidia'' Aspöck & Aspöck, 1968 * '' Raphidia nuchensis'' H. Aspöck et al., 1968 ;subgenus ''Nigroraphidia'' Aspöck & Aspöck, 1968 # '' Raphidia friederikae'' H. Aspöck & U. Aspöck, 1967 # '' Raphidia palaeformis'' H. Aspöck & U. Aspöck, 1964 ;subgenus ''Raphidia'' Linnaeus, 1758 # '' Raphidia alcoholica'' H. Aspöck & U. Aspöck, 1970 # '' Raphidia ambigua'' H. Aspöck & U. Aspöck, 1964 # '' Raphidia ariadne'' H. Aspöck & U. Aspöck, 1964 # '' Raphidia beieri'' H. Aspöck & U. Aspöck, 1964 # '' Raphidia euxina'' Navás, 1915 # '' Raphidia grusinica'' H. Aspöck et al., 1968 # '' R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insect
Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, Thorax (insect anatomy), thorax and abdomen (insect anatomy), abdomen), three pairs of jointed Arthropod leg, legs, compound eyes, and a pair of antenna (biology), antennae. Insects are the most diverse group of animals, with more than a million described species; they represent more than half of all animal species. The insect nervous system consists of a insect brain, brain and a ventral nerve cord. Most insects reproduce Oviparous, by laying eggs. Insects Respiratory system of insects, breathe air through a system of Spiracle (arthropods), paired openings along their sides, connected to Trachea#Invertebrates, small tubes that take air directly to the tissues. The blood therefore does not carry oxygen; it is only partly contained in ves ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hymenoptera
Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are parasitic. Females typically have a special ovipositor for inserting eggs into hosts or places that are otherwise inaccessible. This ovipositor is often modified into a stinger. The young develop through holometabolism (complete metamorphosis)—that is, they have a wormlike larval stage and an inactive pupal stage before they reach adulthood. Etymology The name Hymenoptera refers to the wings of the insects, but the original derivation is ambiguous. All references agree that the derivation involves the Ancient Greek πτερόν (''pteron'') for wing. The Ancient Greek ὑμήν (''hymen'') for membrane provides a plausible etymology for the term because species in this order have membranous wings. However, a key characteristic of this order is that the hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megaloptera
Megaloptera is an order of insects. It contains the alderflies, dobsonflies and fishflies, and there are about 300 known species. The order's name comes from Ancient Greek, from ''mega-'' (μέγα-) "large" + ''pteryx'' (πτέρυξ) "wing", in reference to the large, clumsy wings of these insects. Megaloptera are relatively unknown insects across much of their range, due to the adults' short lives, the aquatic larvae's often-high tolerance of pollution (so they are not often encountered by swimmers etc.), and the generally crepuscular or nocturnal habits. However, in the Americas the dobsonflies are rather well known, as their males have tusk-like mandibles. These, while formidable in appearance, are relatively harmless to humans and other animals; much like a peacock's feathers, they serve mainly to impress females. However, the mandibles are also used to hold females during mating, and some male dobsonflies spar with each other in courtship displays, trying to flip eac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Entomologists' Society
The Amateur Entomologists' Society (AES) is a UK organisation for people interested in insects. History Based in the UK, the Amateur Entomologists' Society was founded in 1935 as The Entomological Exchange and Correspondence Club, for the purpose of providing a forum through which amateur and young entomologists could exchange not only information, but also equipment and other such items. 1937 saw the name of the group changed to the Amateur Entomologists Society, which has remained unchanged since then. The journal of the AES first appeared as The Bulletin in 1939, and it was also during this year that the first non-periodical publication, a leaflet entitled "Coleoptera Collecting", was produced. The Society has advised on invertebrate conservation issues for over 40 years, and has been consulted over legislation such as the UK's Wildlife and Countryside Act 1981, and reviews of the Act. In 1989 the Bulletin became a bi-monthly journal instead of quarterly, and now has a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aeroelastic Flutter
Aeroelasticity is the branch of physics and engineering studying the interactions between the inertial, elastic, and aerodynamic forces occurring while an elastic body is exposed to a fluid flow. The study of aeroelasticity may be broadly classified into two fields: ''static aeroelasticity'' dealing with the static or steady state response of an elastic body to a fluid flow, and ''dynamic aeroelasticity'' dealing with the body's dynamic (typically vibrational) response. Aircraft are prone to aeroelastic effects because they need to be lightweight while enduring large aerodynamic loads. Aircraft are designed to avoid the following aeroelastic problems: # divergence where the aerodynamic forces increase the twist of a wing which further increases forces; # control reversal where control activation produces an opposite aerodynamic moment that reduces, or in extreme cases reverses, the control effectiveness; and # flutter which is uncontained vibration that can lead to the destr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
