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Springtails
Springtails (Collembola) form the largest of the three lineages of modern hexapods that are no longer considered insects (the other two are the Protura and Diplura). Although the three orders are sometimes grouped together in a class called Entognatha because they have internal mouthparts, they do not appear to be any more closely related to one another than they are to all insects, which have external mouthparts. Collembolans are omnivorous, free-living organisms that prefer moist conditions. They do not directly engage in the decomposition of organic matter, but contribute to it indirectly through the fragmentation of organic matter and the control of soil microbial communities. The word ''Collembola'' is from the ancient Greek "glue" and "peg"; this name was given due to the existence of the collophore, which was previously thought to stick to surfaces to stabilize the creature. Some DNA sequence studies suggest that Collembola represent a separate evolutionary line fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexapoda
The subphylum Hexapoda (from Greek for 'six legs') comprises most species of arthropods and includes the insects as well as three much smaller groups of wingless arthropods: Collembola, Protura, and Diplura (all of these were once considered insects). The Collembola (or springtails) are very abundant in terrestrial environments. ''Hexapods'' are named for their most distinctive feature: a consolidated thorax with three pairs of legs (six legs). Most other arthropods have more than three pairs of legs. Most recent studies have recovered Hexapoda as a subgroup of Crustacea. Morphology Hexapods have bodies ranging in length from 0.5 mm to over 300 mm which are divided into an anterior head, thorax, and posterior abdomen. The head is composed of a presegmental ''acron'' that usually bears eyes (absent in Protura and Diplura), followed by six segments, all closely fused together, with the following appendages: :Segment I. None :Segment II. Antennae (sensory), absent in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poduromorpha
The order Poduromorpha is one of the three main groups of springtails (Collembola), tiny hexapods related to insects. This group was formerly treated as a superfamily Poduroidea. They can be best distinguished from the other springtail groups by their body shape. The Symphypleona are very round animals, almost spherical and the abdominal segments are not visible. Both Entomobryomorpha and Poduromorpha are long springtails with six visible abdominal segments. While Entomobryomorpha have the first thorax segment reduced, Poduromorpha retain all three. The Poduromorpha also tend to have short legs and a plump body, but more oval in shape than the Symphypleona. Their name means ‘foot tail formed’, deriving from their short, flat, furcula. Systematics The Poduromorpha were, as Poduroidea, united with the Entomobryomorpha (then called Entomobryoidea) in a group called "Arthropleona", but this has more recently turned out to be paraphyletic. Actually the Entomobryomorpha, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entomobryomorpha
The Entomobryomorpha are one of the three main groups ( order) of springtails (Collembola), tiny hexapods related to insects. This group was formerly treated as a superfamily, the Entomobryoidea. They can be best distinguished from the other springtail groups by their body shape. The Symphypleona are very round animals, almost spherical. The Poduromorpha are also very plump but have a more oval shape. The Entomobryomorpha, by contrast, contain the slimmest springtails. They either have short legs and antennae, but their long bodies set them apart, or long legs and antennae, as well as well-developed furculae; these are the most characteristic members of the order. Systematics The Entomobryomorpha were, as Entomobryoidea, united with the Poduromorpha (then called Poduroidea) in a group called "Arthropleona", but this has more recently turned out to be paraphyletic. Actually, the Entomobryomorpha, the Poduromorpha, and the third springtaill lineage – the Symphypleona – a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symphypleona
The order Symphypleona is one of the three main groups of springtails (Collembola), tiny hexapods related to insects. When the springtails were still believed to be an order of insects, the Symphypleona were ranked as a suborder. They can be best distinguished from the other springtail groups by their body shape. The Symphypleona are very round animals, almost spherical, and usually have long antennae. The Poduromorpha, by contrast, always have short legs and a plump body, but more oval in shape than the Symphypleona. The Entomobryomorpha are the slimmest springtails, some with long and some with short legs and antennae, but always with a very slender body. Systematics The Symphypleona order was previously suggested to also contain family Neelidae, as a very apomorphic relative in the Sminthuridae superfamily. Phylogenetic studies however suggest Neelidae to be the only family of Neelipleona order.Gao, Yan; Bu, Yun & Luan, Yun-Xia (2008): Phylogenetic Relationships of Bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs of jointed legs, compound eyes and one pair of antennae. Their blood is not totally contained in vessels; some circulates in an open cavity known as the haemocoel. Insects are the most diverse group of animals; they include more than a million described species and represent more than half of all known living organisms. The total number of extant species is estimated at between six and ten million; In: potentially over 90% of the animal life forms on Earth are insects. Insects may be found in nearly all environments, although only a small number of species reside in the oceans, which are dominated by another arthropod group, crustaceans, which recent research has indicated insects are nested within. Nearly all insects hatch f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neelipleona
Neelipleona is a name given to some hexapods of the subclass Collembola (springtails). While their taxonomic rank remains broadly settled as family Neelidae, Neelipleona has been described at order or suborder rank. Eyes are absent. Taxonomic rank Many authors consider the "Neelipleona" Symphypleona of the superfamily Sminthuroidea, family Neelidae.See references in Haaramo (2008) However, in other accounts, Neelipleona are either a distinct order from the three less controversial Springtail orders (Entomobryomorpha, Poduromorpha The order Poduromorpha is one of the three main groups of springtails (Collembola), tiny hexapods related to insects. This group was formerly treated as a superfamily Poduroidea. They can be best distinguished from the other springtail group ... and Symphypleona) or a distinct suborder of Symphypleona, or placed in the Entomobryomorpha. References Footnotes Collembola {{springtail-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orchesella Cincta
''Orchesella cincta'' is a species of springtail present in North America and Europe. They average in length, which is extremely large as most springtails don’t grow past 1 millimetre. The specific name ''cincta'' means "belted" and refers to the distinctive colouration of the third abdominal segment. Description Springtails are small, wingless relatives of insects and typically have six abdominal segments, a tubular appendage projecting ventrally from the first abdominal segment, and a forked, tail-like appendage, the furcula, folded under the last abdominal segment, with which the animal can flip itself into the air. Members of the genus ''Orchesella'' have six antennal segments. ''Orchesella cincta'' reaches about in length and has a distinctively pigmented third abdominal segment and a dark third antennal segment. In contrast, the posterior part of the second abdominal segment and the distal part of the second antennal segments are white. The fifth and sixth antennal s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collophore
A collophore is a tube-like structure on the ventral side of the first abdominal segment of the body of springtails (collembolans). It used to be believed that it served to stabilise the animal when it jumped by sticking to the surface on which it moved. However, the current scientific consensus is that it plays a role in osmoregulation, water intake, and excretion Excretion is a process in which metabolic waste is eliminated from an organism. In vertebrates this is primarily carried out by the lungs, kidneys, and skin. This is in contrast with secretion, where the substance may have specific tasks after ....Eisenbeis, G., 1982. Physiological absorption of liquid water by Collembola: absorption by the ventral tube at different salinities. Journal of Insect Physiology 28:11–20. References Springtail anatomy {{arthropod-anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod
Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chitin, often mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an external skeleton. 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. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior organs; it has an open circulatory system. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. Their nervous system is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diplura
The order Diplura ("two-pronged bristletails") is one of three orders of non-insect hexapods within the class Entognatha (alongside Collembola (springtails) and Protura). The name "diplura", or "two tails", refers to the characteristic pair of caudal appendages or filaments at the terminal end of the body. Around 800 species of diplurans have been described, of which around 170 occur in North America and 12 in Great Britain. Anatomy Diplurans are typically long, with most falling between . However, some species of ''Japyx'' may reach . They have no eyes and, apart from the darkened cerci in some species, they are unpigmented. Diplurans have long antennae with 10 or more bead-like segments projecting forward from the head. The abdomens of diplurans bear eversible vesicles, which seem to absorb moisture from the environment and help with the animal's water balance. The body segments themselves may display several types of setae, or scales and setae. Diplurans possess a cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entognatha
The Entognatha are a class of wingless and ametabolous arthropods, which, together with the insects, makes up the subphylum Hexapoda. Their mouthparts are entognathous, meaning that they are retracted within the head, unlike the insects. Entognatha are apterous, meaning that they lack wings. The class contains three orders: Collembola (springtails, 9000 species), Diplura (“two-tail”, 1000 species) and Protura (“first-tail”, 800 species). These three groups were historically united with the now-obsolete order Thysanura to form the class Apterygota, but it has since been recognized that the hexapodous condition of these animals has evolved independently from that of insects, and independently ''within'' each order. The orders may not be closely related, and Entognatha is now considered to be a polyphyletic group. Morphology These minute arthropods are apterous, unlike some orders of insects that have lost their wings secondarily (but are derived from winged ancestors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Phylogenetics And Evolution
''Molecular Phylogenetics and Evolution'' is a peer-reviewed scientific journal of evolutionary biology and phylogenetics. The journal is edited by E.A. Zimmer. Indexing The journal is indexed in: * EMBiology *Journal Citation Reports *Scopus Scopus is Elsevier's abstract and citation database launched in 2004. Scopus covers nearly 36,377 titles (22,794 active titles and 13,583 inactive titles) from approximately 11,678 publishers, of which 34,346 are peer-reviewed journals in top- ... * Web of Science External links * Elsevier academic journals Evolutionary biology journals Phylogenetics Molecular biology Publications established in 1992 Monthly journals {{biology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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