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Holoptic Arrangement
Holoptic refers to one of the ways in which the arthropod eye develops, particularly the eyes of various species of insects. Unlike dichoptic and cycloptic eyes, holoptic eyes meet along the median dorsal line of the head, in many species nearly covering the exterior of the head. Holoptic eyes are typical of several Dipteran males, in particular some Syrphidae, Tabanidae, Pipunculidae, and Acroceridae. Some other insect orders that include species with holoptic males and some in which the females are holoptic as well, include the Coleoptera, Anisoptera, and Archaeognatha The Archaeognatha are an order of apterygotes, known by various common names such as jumping bristletails. Among extant insect taxa they are some of the most evolutionarily primitive; they appeared in the Middle Devonian period at about the sa .... References * {{Insect-anatomy-stub Insect anatomy Eye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eristalinus October 2007-6a
''Eristalinus'' is a genus of hoverfly. Most species have very distinctive eye marking in the form of spots or banding, though these features may fade on some preserved specimens. Most are stout flies, and are nimble flyers, even compared to other hoverfly species. Systematics At one time the members of this genus were divided into three clades (''Eristalinus'', ''Eristalodes'' and ''Lathyrophthalmus'') based on morphological characters such as whether the eyes were spotted or striped. Recently Pérez-Bañon ''et al.'' studying the European species of ''Eristalinus'' using a combination of molecular data and male genitalia characters have determined that the genus in Europe at least, divides neatly into two clades - ''Eristalinus'' (+ ''Lathyrophthalmus'') & ''Eristalodes''. It was also discovered that the eye patterning was not taxonomically important as ''Eristalodes'' contained members with eyes either spotted or striped. The following list is an attempt to organise some of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod Eye
Apposition eyes are the most common form of eye, and are presumably the ancestral form of compound eye. They are found in all arthropod groups, although they may have evolved more than once within this phylum. Some annelids and bivalves also have apposition eyes. They are also possessed by ''Limulus'', the horseshoe crab, and there are suggestions that other chelicerates developed their simple eyes by reduction from a compound starting point. Some caterpillars appear to have evolved compound eyes from simple eyes in the opposite fashion. The arthropods ancestrally possessed compound eyes, but the type and origin of this eye varies between groups, and some taxa have secondarily developed simple eyes. The organ's development through the lineage can be estimated by comparing groups that branched early, such as the velvet worm and horseshoe crab to the advanced eye condition found in insects and other derived arthropods. Eyes and functions Most arthropods have at least one of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compound Eye
A compound eye is a visual organ found in arthropods such as insects and crustaceans. It may consist of thousands of ommatidia, which are tiny independent photoreception units that consist of a cornea, lens, and photoreceptor cells which distinguish brightness and color. The image perceived by this arthropod eye is a combination of inputs from the numerous ommatidia, which are oriented to point in slightly different directions. Compared with single-aperture eyes, compound eyes have poor image resolution; however, they possess a very large view angle and the ability to detect fast movement and, in some cases, the polarization of light. Because a compound eye is made up of a collection of ommatidia, each with its own lens, light will enter each ommatidium instead of using a single entrance point. The individual light receptors behind each lens are then turned on and off due to a series of changes in the light intensity during movement or when an object in moving, creating a flic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichoptic Arrangement
Apposition eyes are the most common form of eye, and are presumably the ancestral form of compound eye. They are found in all arthropod groups, although they may have evolved more than once within this phylum. Some annelids and bivalves also have apposition eyes. They are also possessed by ''Limulus'', the horseshoe crab, and there are suggestions that other chelicerates developed their simple eyes by reduction from a compound starting point. Some caterpillars appear to have evolved compound eyes from simple eyes in the opposite fashion. The arthropods ancestrally possessed compound eyes, but the type and origin of this eye varies between groups, and some taxa have secondarily developed simple eyes. The organ's development through the lineage can be estimated by comparing groups that branched early, such as the velvet worm and horseshoe crab to the advanced eye condition found in insects and other derived arthropods. Eyes and functions Most arthropods have at least one of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycloptic Arrangement
Apposition eyes are the most common form of eye, and are presumably the ancestral form of compound eye. They are found in all arthropod groups, although they may have evolved more than once within this phylum. Some annelids and bivalves also have apposition eyes. They are also possessed by ''Limulus'', the horseshoe crab, and there are suggestions that other chelicerates developed their simple eyes by reduction from a compound starting point. Some caterpillars appear to have evolved compound eyes from simple eyes in the opposite fashion. The arthropods ancestrally possessed compound eyes, but the type and origin of this eye varies between groups, and some taxa have secondarily developed simple eyes. The organ's development through the lineage can be estimated by comparing groups that branched early, such as the velvet worm and horseshoe crab to the advanced eye condition found in insects and other derived arthropods. Eyes and functions Most arthropods have at least one of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsum (biology)
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axis, anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diptera
Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced mechanosensory organs known as halteres, which act as high-speed sensors of rotational movement and allow dipterans to perform advanced aerobatics. Diptera is a large order containing an estimated 1,000,000 species including horse-flies, crane flies, hoverflies and others, although only about 125,000 species have been described. Flies have a mobile head, with a pair of large compound eyes, and mouthparts designed for piercing and sucking (mosquitoes, black flies and robber flies), or for lapping and sucking in the other groups. Their wing arrangement gives them great maneuverability in flight, and claws and pads on their feet enable them to cling to smooth surfaces. Flies undergo complete metamorphosis; the eggs are often laid on the l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horse-fly
Horse-flies or horseflies are true Fly, flies in the family Tabanidae in the insect Order (biology), order Diptera. They are often large and agile in flight, and only the female horseflies bite animals, including humans, to hematophagy, obtain blood. They prefer to fly in sunlight, avoiding dark and shady areas, and are inactive at night. They are found all over the world except for some islands and the polar regions (Hawaii, Greenland, Iceland). Both horse-flies and Botfly, botflies (Oestridae) are sometimes referred to as gadflies. Adult horse-flies feed on nectar and plant exudates; the males have weak insect mouthparts, mouthparts and only the females bite animals to obtain enough protein from blood to produce eggs. The mouthparts of females are formed into a stout stabbing organ with two pairs of sharp cutting blades, and a spongelike part used to lap up the blood that flows from the wound. The larvae are Predation, predaceous and grow in semiaquatic habitats. Female hor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pipunculidae
Pipunculidae is a family of flies (Diptera) commonly termed big-headed flies, a reference to the large (holoptic) eyes, which cover nearly the entire head. The family is found worldwide and more than 1300 species have been described. The larvae of Pipunculidae develop as parasitoids almost exclusively in Auchenorrhyncha, the exception being the genus ''Nephrocerus'', whose hosts are adult Tipulidae (crane flies). The larvae develop rapidly within the crane flies before pupating in the soil. In all pipunculids there are only two larval stages. Some species are used as biological control agents in rice fields. Taxonomy Taxonomy as shown at the Tree of life, with modification based on Kehlmaier, Dierick and Skevington (2014). The name Pipunculidae is derived from the type genus ''Pipunculus'' which is thought to be derived from Latin ''pepo'' for pumpkin, thus pipunculus would mean "little pumpkin", referring to the large heads. Subfamily Chalarinae * Genus ''Chalarus'' Walker ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acroceridae
The Acroceridae are a small family (biology), family of odd-looking flies. They have a hump-backed appearance with a strikingly small head, generally with a long proboscis for accessing nectar. They are rare and not widely known. The most frequently applied common names are small-headed flies or hunch-back flies. Many are bee or wasp mimicry, mimics. Because they are parasitoids of spiders, they also are sometimes known as spider flies. Description The Acroceridae vary in size from small to fairly large, about the size of large bees, with a wingspan over 25 mm in some species. As a rule, both sexes have tiny heads and a characteristic hump-backed appearance because of the large, rounded thorax. In appearance, they are compact flies without major bristles, but many species have a bee-like hairiness on their bodies, and some are bee or wasp mimicry, mimics. In most species, the eyes are holoptic in both sexes, the heads seemingly composed mainly of the large ommatidia, facete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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