Order ( Latin : ordo ) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy . It is classified between family and class . In biological classification , the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes . An immediately higher rank, superorder , is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families.
37-401: 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
74-461: A cohors (plural cohortes ). Some of the plant families still retain the names of Linnaean "natural orders" or even the names of pre-Linnaean natural groups recognized by Linnaeus as orders in his natural classification (e.g. Palmae or Labiatae ). Such names are known as descriptive family names. In the field of zoology , the Linnaean orders were used more consistently. That is,
111-502: 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. 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
148-509: A capital letter. For some groups of organisms, their orders may follow consistent naming schemes . Orders of plants , fungi , and algae use the suffix -ales (e.g. Dictyotales ). Orders of birds and fishes use the Latin suffix -iformes meaning 'having the form of' (e.g. Passeriformes ), but orders of mammals and invertebrates are not so consistent (e.g. Artiodactyla , Actiniaria , Primates ). For some clades covered by
185-411: A considerable number, keeping the wings gripped together especially tightly. Hymenopteran wings have relatively few veins compared with many other insects, especially in the smaller species. In the more ancestral hymenopterans, the ovipositor is blade-like, and has evolved for slicing plant tissues. In the majority, however, it is modified for piercing, and, in some cases, is several times the length of
222-570: A distinct rank of biological classification having its own distinctive name (and not just called a higher genus ( genus summum )) was first introduced by the German botanist Augustus Quirinus Rivinus in his classification of plants that appeared in a series of treatises in the 1690s. Carl Linnaeus was the first to apply it consistently to the division of all three kingdoms of nature (then minerals , plants , and animals ) in his Systema Naturae (1735, 1st. Ed.). For plants, Linnaeus' orders in
259-585: A male, instead. This is especially likely to occur in an individual whose parents were siblings or other close relatives. Diploid males are known to be produced by inbreeding in many ant, bee, and wasp species. Diploid biparental males are usually sterile but a few species that have fertile diploid males are known. One consequence of haplodiploidy is that females on average have more genes in common with their sisters than they do with their daughters. Because of this, cooperation among kindred females may be unusually advantageous and has been hypothesized to contribute to
296-708: A nymph with a prominent role at the wedding of Zeus. Molecular analysis finds that Hymenoptera is the earliest branching group of Holometabola . Hymenoptera (sawflies, wasps) [REDACTED] Coleoptera (beetles) [REDACTED] Strepsiptera (twisted-wing parasites) [REDACTED] Raphidioptera (snakeflies) [REDACTED] Megaloptera (alderflies and allies) [REDACTED] Neuroptera (Lacewings and allies) [REDACTED] Lepidoptera (butterflies, moths) [REDACTED] Trichoptera (caddisflies) [REDACTED] Diptera [REDACTED] Mecoptera (scorpionflies) [REDACTED] Siphonaptera (fleas) [REDACTED] Hymenoptera originated in
333-483: A plausible etymology for the term because species in this order have membranous wings. However, a key characteristic of this order is that the hindwings are connected to the forewings by a series of hooks . Thus, another plausible etymology involves Hymen , the Ancient Greek god of marriage, as these insects have married wings in flight. Another suggestion for the inclusion of Hymen is the myth of Melissa ,
370-409: A wide range of feeding habits. The most primitive forms are typically phytophagous, feeding on flowers, pollen, foliage, or stems. Stinging wasps are predators, and will provision their larvae with immobilised prey, while bees feed on nectar and pollen . A huge number of species are parasitoids as larvae. The adults inject the eggs into a host, which they begin to consume after hatching. For example,
407-440: Is determined by the number of chromosomes an individual possesses. Fertilized eggs get two sets of chromosomes (one from each parent's respective gametes ) and develop into diploid females, while unfertilized eggs only contain one set (from the mother) and develop into haploid males. The act of fertilization is under the voluntary control of the egg-laying female, giving her control of the sex of her offspring. This phenomenon
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#1732765526680444-402: Is called haplodiploidy . However, the actual genetic mechanisms of haplodiploid sex determination may be more complex than simple chromosome number. In many Hymenoptera, sex is determined by a single gene locus with many alleles. In these species, haploids are male and diploids heterozygous at the sex locus are female, but occasionally a diploid will be homozygous at the sex locus and develop as
481-419: Is determined by a taxonomist , as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with
518-528: The International Code of Zoological Nomenclature , several additional classifications are sometimes used, although not all of these are officially recognized. In their 1997 classification of mammals , McKenna and Bell used two extra levels between superorder and order: grandorder and mirorder . Michael Novacek (1986) inserted them at the same position. Michael Benton (2005) inserted them between superorder and magnorder instead. This position
555-815: The Systema Naturae and the Species Plantarum were strictly artificial, introduced to subdivide the artificial classes into more comprehensible smaller groups. When the word ordo was first consistently used for natural units of plants, in 19th-century works such as the Prodromus Systematis Naturalis Regni Vegetabilis of Augustin Pyramus de Candolle and the Genera Plantarum of Bentham & Hooker, it indicated taxa that are now given
592-590: The Triassic , with the oldest fossils belonging to the family Xyelidae . Social hymenopterans appeared during the Cretaceous . The evolution of this group has been intensively studied by Alex Rasnitsyn , Michael S. Engel , and others. Phylogenetic relationships within the Hymenoptera, based on both morphology and molecular data, have been intensively studied since 2000. In 2023, a molecular study based on
629-401: The genetic load of deleterious genes is purged relatively quickly. Some hymenopterans take advantage of parthenogenesis , the creation of embryos without fertilization . Thelytoky is a particular form of parthenogenesis in which female embryos are created (without fertilisation). The form of thelytoky in hymenopterans is a kind of automixis in which two haploid products (proto-eggs) from
666-493: The Cape honey bee Apis mellifera capensis . Oocytes that undergo automixis with central fusion often have a reduced rate of crossover recombination , which helps to maintain heterozygosity and avoid inbreeding depression . Species that display central fusion with reduced recombination include the ants Platythyrea punctata and Wasmannia auropunctata and the Cape honey bee Apis mellifera capensis . In A. m. capensis ,
703-826: The analysis of ultra-conserved elements confirmed many previous findings and produced a relatively robust phylogeny of the whole Order. Basal superfamilies are shown in the cladogram below. Tenthredinoidea [REDACTED] Xyeloidea ( Triassic -present) [REDACTED] Pamphilioidea [REDACTED] Siricoidea (horntails or wood wasps) [REDACTED] Xiphydrioidea (wood wasps) [REDACTED] Cephoidea (stem sawflies) [REDACTED] Orussoidea ( parasitic wood wasps) [REDACTED] Apocrita ( ants , bees , wasps ) [REDACTED] Hymenopterans range in size from very small to large insects, and usually have two pairs of wings. Their mouthparts are adapted for chewing, with well-developed mandibles (ectognathous mouthparts). Many species have further developed
740-428: The body. In some species, the ovipositor has become modified as a stinger , and the eggs are laid from the base of the structure, rather than from the tip, which is used only to inject venom . The sting is typically used to immobilize prey, but in some wasps and bees may be used in defense. Hymenopteran larvae typically have a distinct head region, three thoracic segments, and usually nine or 10 abdominal segments. In
777-419: The eggs of the endangered Papilio homerus are parasitized at a rate of 77%, mainly by Hymenoptera species. Some species are even hyperparasitoid , with the host itself being another parasitoid insect. Habits intermediate between those of the herbivorous and parasitoid forms are shown in some hymenopterans, which inhabit the galls or nests of other insects, stealing their food, and eventually killing and eating
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#1732765526680814-454: The exception of some bee larvae where the larval anus has reappeared through developmental reversion. In general, the anus only opens at the completion of larval growth. Hymenoptera as a group are highly susceptible to habitat loss, which can lead to substantial decreases in species richness and have major ecological implications due to their pivotal role as plant pollinators. Order (biology) What does and does not belong to each order
851-417: The mouthparts into a lengthy proboscis , with which they can drink liquids, such as nectar . They have large compound eyes , and typically three simple eyes, ocelli . The forward margin of the hind wing bears a number of hooked bristles, or " hamuli ", which lock onto the fore wing, keeping them held together. The smaller species may have only two or three hamuli on each side, but the largest wasps may have
888-470: The multiple origins of eusociality within this order. In many colonies of bees, ants, and wasps, worker females will remove eggs laid by other workers due to increased relatedness to direct siblings, a phenomenon known as worker policing . Another consequence is that hymenopterans may be more resistant to the deleterious effects of inbreeding . As males are haploid, any recessive genes will automatically be expressed, exposing them to natural selection. Thus,
925-524: The occupant. The Hymenoptera are divided into two groups; the Symphyta which have no waist, and the Apocrita which have a narrow waist. The suborder Symphyta includes the sawflies , horntails , and parasitic wood wasps . The group may be paraphyletic , as it has been suggested that the family Orussidae may be the group from which the Apocrita arose. They have an unconstricted junction between
962-708: The orders in the zoology part of the Systema Naturae refer to natural groups. Some of his ordinal names are still in use, e.g. Lepidoptera (moths and butterflies) and Diptera (flies, mosquitoes, midges, and gnats). In virology , the International Committee on Taxonomy of Viruses 's virus classification includes fifteen taxomomic ranks to be applied for viruses , viroids and satellite nucleic acids : realm , subrealm , kingdom , subkingdom, phylum , subphylum , class, subclass, order, suborder, family, subfamily , genus, subgenus , and species. There are currently fourteen viral orders, each ending in
999-564: The precursor of the currently used International Code of Nomenclature for algae, fungi, and plants . In the first international Rules of botanical nomenclature from the International Botanical Congress of 1905, the word family ( familia ) was assigned to the rank indicated by the French famille , while order ( ordo ) was reserved for a higher rank, for what in the 19th century had often been named
1036-502: The rank of family (see ordo naturalis , ' natural order '). In French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille (plural: familles ) was used as a French equivalent for this Latin ordo . This equivalence was explicitly stated in the Alphonse Pyramus de Candolle 's Lois de la nomenclature botanique (1868),
1073-419: The recombination rate during meiosis is reduced more than tenfold. In W. auropunctata the reduction is 45 fold. Single queen colonies of the narrow headed ant Formica exsecta illustrate the possible deleterious effects of increased homozygosity. Colonies of this species which have more homozygous queens will age more rapidly, resulting in reduced colony survival. Different species of Hymenoptera show
1110-409: The same meiosis fuse to form a diploid zygote. This process tends to maintain heterozygosity in the passage of the genome from mother to daughter. It is found in several ant species including the desert ant Cataglyphis cursor , the clonal raider ant Cerapachys biroi , the predaceous ant Platythyrea punctata , and the electric ant (little fire ant) Wasmannia auropunctata . It also occurs in
1147-438: The suborder Symphyta , the eruciform larvae resemble caterpillars in appearance, and like them, typically feed on leaves. They have large chewing mandibles, three pairs of thoracic limbs, and, in most cases, six or eight abdominal prolegs . Unlike caterpillars, however, the prolegs have no grasping spines, and the antennae are reduced to mere stubs. Symphytan larvae that are wood borers or stem borers have no abdominal legs and
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1184-399: The suborder (and clade) Apocrita , characterized by a constriction between the first and second abdominal segments called a wasp-waist ( petiole ), also involving the fusion of the first abdominal segment to the thorax . Also, the larvae of all Apocrita lack legs, prolegs, or ocelli. The hindgut of the larvae also remains closed during development, with feces being stored inside the body, with
1221-477: The suffix -virales . Siricoidea The superfamily Siricoidea is an archaic group of the order Hymenoptera , consisting of six families (four extinct) of xylophagous sawflies . The group is well represented in early Tertiary and Mesozoic times, but a number of living taxa remain, including the family Anaxyelidae , which has recently been linked to this group (it was previously placed in its own superfamily, Anaxyeloidea). The female ovipositor
1258-427: The thoracic legs are smaller than those of non-borers. With rare exceptions, larvae of the suborder Apocrita have no legs and are maggotlike in form, and are adapted to life in a protected environment. This may be the body of a host organism, or a cell in a nest, where the adults will care for the larva. In parasitic forms, the head is often greatly reduced and partially withdrawn into the prothorax (anterior part of
1295-518: The thorax and abdomen. The larvae are herbivorous, free-living, and eruciform , usually with three pairs of true legs, prolegs (on every segment, unlike Lepidoptera ) and ocelli . The prolegs do not have crochet hooks at the ends unlike the larvae of the Lepidoptera. The legs and prolegs tend to be reduced or absent in larvae that mine or bore plant tissue, as well as in larvae of Pamphiliidae . The wasps , bees , and ants together make up
1332-522: The thorax). Sense organs appear to be poorly developed, with no ocelli, very small or absent antennae, and toothlike, sicklelike, or spinelike mandibles. They are also unable to defecate until they reach adulthood due to having an incomplete digestive tract (a blind sac), presumably to avoid contaminating their environment. The larvae of stinging forms ( Aculeata ) generally have 10 pairs of spiracles, or breathing pores, whereas parasitic forms usually have nine pairs present. Among most or all hymenopterans, sex
1369-418: Was adopted by Systema Naturae 2000 and others. In botany , the ranks of subclass and suborder are secondary ranks pre-defined as respectively above and below the rank of order. Any number of further ranks can be used as long as they are clearly defined. The superorder rank is commonly used, with the ending -anae that was initiated by Armen Takhtajan 's publications from 1966 onwards. The order as
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