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Alderflies
Alderflies are megalopteran insects of the family Sialidae. They are closely related to the dobsonflies and fishflies as well as to the prehistoric Euchauliodidae. All living alderflies – about 66 species all together – are part of the subfamily Sialinae, which contains between one and seven extant genera according to different scientists' views. Description Sialinae have a body length of less than 25 mm (1 inch), long filamentous antennae, and four large dark wings of which the anterior pair is slightly longer than the posterior. They lack ocelli and their fourth tarsal segment is dilated and deeply bilobed. Dead alderfly larvae are used as bait in fishing. Life cycle The females lay a vast number of eggs on grass stems near water. When the larvae are born they drop into the water or the ground nearby it and make their way into their new aquatic biome. The larvae are aquatic, active, armed with strong sharp mandibles, and breathe by means of seven pairs of a ... [...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 each ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dobsonflies
Dobsonflies are a subfamily of insects, Corydalinae, part of the Megalopteran family Corydalidae. The larvae (commonly called hellgrammites) are aquatic, living in streams, and the adults are often found along streams as well. The nine genera of dobsonflies are distributed in the Americas, Asia, and South Africa. Etymology The origin of the word "dobsonfly" is unclear. John Henry Comstock used the term in reference to these insects in his 1897 book ''Insect Life'', but did not explain it. He also mentioned that anglers used the word "hellgrammite" for the aquatic larvae they used as bait, but the origin of this term is also unknown. Description Adult dobsonflies are some of the largest non-Lepidopteran insects of temperate zones such as the United States and Canada, with a wingspan of up to in some species of ''Corydalus''.Stange, Lionel. "Alderflies and Dobsonflies." Encyclopedia of Entomology. 2nd ed. New York: Springer Publishing, 2008. The Asian ''Acanthacorydalis fruhsto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insect Wing
Insect wings are adult outgrowths of the insect exoskeleton that enable insects to fly. They are found on the second and third 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 dragonflies and 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 or even genus level in many 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 wing base, so that a small downward movement of the wing base lifts the wing itself upward. Those i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sialis Lutaria Larva (aka)
''Sialis'' is a genus of alderfly belonging to the order Megaloptera family Sialidae. Description These alderflies are small and mainly brown with a relatively heavy body and forewings reaching a length of 10 to 20 millimeters. Females are usually larger than males. They have wings with large cells forming a network. The upper edge of the front wings consists of almost square cells. The species belonging to the genus ''Sialis'' have less than fifteen square cells, while the other Megaloptera have more cells. The adults are diurnal and fly from May to June on the riparian vegetation. Females lay on the leaves of the shore plants up to 2000 eggs in groups of about 200. The resulting hatching larvae fall directly into the water. They live in the water at first, and later buried in the mud, up to 18 meters of depth. These larvae feed on larvae of insects, worms and small molluscs. They usually need two years to develop, overwintering as larvae. Pupation takes place on the shore u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sialis Larva Packard
''Sialis'' is a genus of alderfly belonging to the order Megaloptera family Sialidae. Description These alderflies are small and mainly brown with a relatively heavy body and forewings reaching a length of 10 to 20 millimeters. Females are usually larger than males. They have wings with large cells forming a network. The upper edge of the front wings consists of almost square cells. The species belonging to the genus ''Sialis'' have less than fifteen square cells, while the other Megaloptera have more cells. The adults are diurnal and fly from May to June on the riparian vegetation. Females lay on the leaves of the shore plants up to 2000 eggs in groups of about 200. The resulting hatching larvae fall directly into the water. They live in the water at first, and later buried in the mud, up to 18 meters of depth. These larvae feed on larvae of insects, worms and small molluscs. They usually need two years to develop, overwintering as larvae. Pupation takes place on the shore u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sialis Lutaria
''Sialis lutaria'', common name alderfly, is a species of alderfly belonging to the order Megaloptera family Sialidae. Distribution This species is mainly present in Austria, Belgium, United Kingdom, Czech Republic, France, Germany, Italy, the Netherlands, Spain, Poland, Romania and Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel .... Habitat Adults of this species usually inhabits ponds and slow-flowing streams, while the larvae live in mud and detritus under water. Description Adults can reach of length, with a wingspan of . Olsen, L., Sunesen, J., & Pedersen, B. V. (1999) Small freshwater creatures. Oxford University Press, Oxford. They have a stocky body with a black or dark brown basic coloration, including head and legs. The wings are greyish, membranous and tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphosis
Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some insects, fish, amphibians, mollusks, crustaceans, cnidarians, echinoderms, and tunicates undergo metamorphosis, which is often accompanied by a change of nutrition source or behavior. Animals can be divided into species that undergo complete metamorphosis (" holometaboly"), incomplete metamorphosis ("hemimetaboly"), or no metamorphosis (" ametaboly"). Scientific usage of the term is technically precise, and it is not applied to general aspects of cell growth, including rapid growth spurts. Generally organisms with a larva stage undergo metamorphosis, and during metamorphosis the organism loses larval characteristics. References to "metamorphosis" in mammals are imprecise and only colloquial, but historically idealist ideas of transformation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toarcian
The Toarcian is, in the ICS' geologic timescale, an age and stage in the Early or Lower Jurassic. It spans the time between 182.7 Ma (million years ago) and 174.1 Ma. It follows the Pliensbachian and is followed by the Aalenian. The Toarcian Age began with the Toarcian turnover, the extinction event that sets its fossil faunas apart from the previous Pliensbachian age. It is believed to have ended with a global cooling event known as the Comptum Cooling Event, although whether it represented a worldwide event is controversial. Stratigraphic definitions The Toarcian takes its name from the city of Thouars, just south of Saumur in the Loire Valley of France. The stage was introduced by French palaeontologist Alcide d'Orbigny in 1842, after examining rock strata of this age in a quarry near Thouars. In Europe this period is represented by the upper part of the Lias. The base of the Toarcian is defined as the place in the stratigraphic record where the ammonite genus '' Eoda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ciechocinek Formation
The Ciechocinek Formation (also known as the Gryfice Formation at Suliszewo), formerly known in Germany as the Green Series (German: ''Grüne Serie'') is a Jurassic (lower Toarcian) geologic formation that extends across the Baltic coast, from Grimmen, Germany, to Lithuania, with its major sequence in Poland and a few boreholes in Kaliningrad. It is mostly known by its diverse entomofauna, composed of more than 150 species of different groups of insects, as well its marine vertebrate fossils, including remains of sharks, actinopterygians and marine reptiles, along terrestrial remains of dinosaurs, including the early thyreophoran ''Emausaurus'' and others not yet assigned to a definite genus. Its exposures are mostly derived from active clay mining of a dislocated glacial raft with exposed Upper Pliensbachian to late Toarcian shallow-marine sediments. Starting with coarse and fine sand deposits with concretions, the pure clay of the Ciechocinek Formation, after the falciferum zon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gill
A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are kept moist. The microscopic structure of a gill presents a large surface area to the external environment. Branchia (pl. branchiae) is the zoologists' name for gills (from Ancient Greek ). With the exception of some aquatic insects, the filaments and lamellae (folds) contain blood or coelomic fluid, from which gases are exchanged through the thin walls. The blood carries oxygen to other parts of the body. Carbon dioxide passes from the blood through the thin gill tissue into the water. Gills or gill-like organs, located in different parts of the body, are found in various groups of aquatic animals, including mollusks, crustaceans, insects, fish, and amphibians. Semiterrestrial marine animals such as crabs and mudskippers have gill cham ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
