Hymenoptera

Last updated

Hymenoptera
Temporal range: Triassicpresent 235–0  Ma [1]
Sphex pensylvanicus.jpg
A digger wasp, Sphex pensylvanicus
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
(unranked): Endopterygota
Superorder: Hymenopterida
Order: Hymenoptera
Linnaeus, 1758
Suborders

Apocrita
Symphyta

Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, [2] [3] in addition to over 2,000 extinct ones. [4] Many of the species are parasitic.

Contents

Females typically have a special ovipositor for inserting eggs into hosts or places that are otherwise inaccessible. The ovipositor is often modified into a stinger. The young develop through holometabolism (complete metamorphosis)—that is, they have a worm-like larval stage and an inactive pupal stage before they mature.

Etymology

The name Hymenoptera refers to the wings of the insects, but the original derivation is ambiguous. [5] :42 All references agree that the derivation involves the Ancient Greek πτερόν (pteron) for wing. [6] The Ancient Greek ὑμήν (hymen) for membrane provides a plausible etymology for the term because species in this order have membranous wings. [6] However, a key characteristic of this order is that the hind wings are connected to the fore wings 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.

Evolution

The cladogram of external relationships, based on a 2008 DNA and protein analysis, shows the order as a clade, most closely related to endopterygote orders including the Diptera (true flies) and Lepidoptera (butterflies and moths). [7] [8] [9] [10]

Panzygothoraca
Panorpida
Antliophora

Diptera (true flies) Common house fly, Musca domestica.jpg

Mecopteroidea

Nannochoristidae

Mecoptera  (scorpionflies, hangingflies)

Gunzesrieder Tal Insekt 3.jpg

(exc. Boreidae, Nannochoristidae)

Boreidae (snow scorpionflies) Boreus hiemalis2 detail.jpg

Siphonaptera (fleas) Pulex irritans female ZSM.jpg

Amphiesmenoptera

Trichoptera (caddisflies) Sericostoma.personatum.jpg

Lepidoptera (butterflies and moths) Tyria jacobaeae-lo.jpg

Hymenoptera (sawflies, wasps, ants, bees) AD2009Sep09 Vespula germanica 03.jpg

(part of  Endopterygota)

Hymenoptera originated in the Triassic, with the oldest fossils belonging to the family Xyelidae. Social hymenopterans appeared during the Cretaceous. [11] The evolution of this group has been intensively studied by Alex Rasnitsyn, Michael S. Engel, and others. [12]

This clade has been studied by examining the mitochondrial DNA. [13] Although this study was unable to resolve all the ambiguities in this clade, some relationships could be established. The Aculeata, Ichneumonomorpha, and Proctotrupomorpha were monophyletic. The Megalyroidea and Trigonalyoidea are sister clades as are the Chalcidoidea+Diaprioidea. The Cynipoidea was generally recovered as the sister group to Chalcidoidea and Diaprioidea which are each other's closest relations. The cladogram is based on Schulmeister 2003. [14] [15]

Hymenoptera
Hymenoptera

Xyeloidea (Triassic-present) Xyelapusilla.jpg

Tenthredinoidea Endelomyia rosae.jpg

Pamphilioidea Pamphilus icon.png

Unicalcarida

Cephoidea (stem sawflies) Hartigia linearis.jpg

Siricoidea (horntails or wood wasps) Hymenoptera Vielfalt Horntail.jpg

Xiphydrioidea (wood wasps) Xiphydria prolongata crop.jpg

parasitism

Orussoidea (parasitic wood wasps) Orussus coronatus.jpg

"wasp waist"

Apocrita (ants, bees, wasps) Specimen of Podalonia tydei (Le Guillou, 1841).jpg

200mya
250mya
Symphyta (red bar) are paraphyletic as Apocrita are excluded.

Anatomy

Bombus muscorum drinking nectar with its long proboscis Bombus muscorum1.jpg
Bombus muscorum drinking nectar with its long proboscis

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 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 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 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 immobilise prey, but in some wasps and bees may be used in defense. [11]

Hymenopteran larvae typically have a distinct head region, three thoracic segments, and usually nine or 10 abdominal segments. In the suborder Symphyta, the 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 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 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. [11] The larvae of stinging forms (Aculeata) generally have 10 pairs of spiracles, or breathing pores, whereas parasitic forms usually have nine pairs present. [16]

Reproduction

Sex determination

Among most or all hymenopterans, sex is determined by the number of chromosomes an individual possesses. [17] 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. [11] This phenomenon 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 actually determined by a single gene locus with many alleles. [17] 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 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. [18]

One consequence of haplodiploidy is that females on average actually have more genes in common with their sisters than they do with their own daughters. Because of this, cooperation among kindred females may be unusually advantageous, and has been hypothesized to contribute to the multiple origins of eusociality within this order. [11] [19] 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. [20]

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, the genetic load of deleterious genes is purged relatively quickly. [21]

Thelytoky

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 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 , [22] the clonal raider ant Cerapachys biroi , [23] the predaceous ant Platythyrea punctata , [24] and the electric ant (little fire ant) Wasmannia auropunctata . [25] It also occurs in the Cape honey bee Apis mellifera capensis . [26]

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 [24] and Wasmannia auropunctata [25] and the Cape honey bee Apis mellifera capensis. [26] In A. m. capensis, the recombination rate during meiosis is reduced more than tenfold. [26] In W. auropunctata the reduction is 45 fold. [25]

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. [27]

Diet

Different species of Hymenoptera show 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, the eggs of the endangered Papilio homerus are parasitized at a rate of 77%, mainly by Hymenoptera species. [28] 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 the occupant. [11]

Classification

Symphyta, without a waist: the sawfly Arge pagana Large rose sawfly (Arge pagana stephensii).jpg
Symphyta, without a waist: the sawfly Arge pagana
Apocrita, with narrow waist: the wasp Vespula germanica AD2009Sep09 Vespula germanica 01.jpg
Apocrita, with narrow waist: the wasp Vespula germanica

The Hymenoptera are divided into two groups; the Symphyta which have no waist, and the Apocrita which have a narrow waist. [4]

Symphyta

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 the thorax and abdomen. The larvae are herbivorous, free-living, and eruciform, 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. [4]

Apocrita

The wasps, bees, and ants together make up 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 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. [4]

See also

Related Research Articles

Mutillidae Family of wasps

The Mutillidae are a family of more than 7,000 species of wasps whose wingless females resemble large, hairy ants. Their common name velvet ant refers to their dense pile of hair, which most often is bright scarlet or orange, but may also be black, white, silver, or gold. Their bright colors serve as aposematic signals. They are known for their extremely painful stings,, hence the common name cow killer or cow ant. However, mutillids are not aggressive and sting only in defense. In addition, the actual toxicity of their venom is much lower than that of honey bees or harvester ants. Unlike true ants, they are solitary, and lack complex social systems.

Sawfly Suborder of insects

Sawflies are the insects of the suborder Symphyta within the order Hymenoptera alongside ants, bees and wasps. The common name comes from the saw-like appearance of the ovipositor, which the females use to cut into the plants where they lay their eggs. The name is associated especially with the Tenthredinoidea, by far the largest superfamily in the suborder, with about 7,000 known species; in the entire suborder, there are 8,000 described species in more than 800 genera. Symphyta is paraphyletic, consisting of several basal groups within the order Hymenoptera, each one rooted inside the previous group, ending with the Apocrita which are not sawflies.

Apocrita

The Apocrita are a suborder of insects in the order Hymenoptera. It includes wasps, bees, and ants, and consists of many families. It contains the most advanced hymenopterans and is distinguished from Symphyta by the narrow "waist" (petiole) formed between the first two segments of the actual abdomen; the first abdominal segment is fused to the thorax, and is called the propodeum. Therefore, it is general practice, when discussing the body of an apocritan in a technical sense, to refer to the mesosoma and metasoma rather than the "thorax" and "abdomen", respectively. The evolution of a constricted waist was an important adaption for the parasitoid lifestyle of the ancestral apocritan, allowing more maneuverability of the female's ovipositor. The ovipositor either extends freely or is retracted, and may be developed into a stinger for both defense and paralyzing prey. Larvae are legless and blind, and either feed inside a host or in a nest cell provisioned by their mothers.

Ichneumonoidea

The superfamily Ichneumonoidea contains one extinct and three extant families, including the two largest families within Hymenoptera: Ichneumonidae and Braconidae. The group is thought to contain as many as 100,000 species, many of which have not yet been described. Like other parasitoid wasps, they were long placed in the "Parasitica", variously considered as an infraorder or an unranked clade, now known to be paraphyletic.

Thelytoky

Thelytoky is a type of parthenogenesis in which females are produced from unfertilized eggs, as for example in aphids. Thelytokous parthenogenesis is rare among animals and reported in about 1,500 species, about 1 in 1000 of described animal species, according to a 1984 study. It is more common in invertebrates, like arthropods, but it can occur in vertebrates, including salamanders, fish, and reptiles such as some whiptail lizards.

Arrhenotoky

Arrhenotoky, also known as arrhenotokous parthenogenesis, is a form of parthenogenesis in which unfertilized eggs develop into males. In most cases, parthenogenesis produces exclusively female offspring, hence the distinction.

Alexandr Rasnitsyn

Alexandr Pavlovich Rasnitsyn is a Russian entomologist, expert in palaeoentomology, and Honored Scientist of the Russian Federation (2001). His scientific interests are centered on the palaeontology, phylogeny, and taxonomy of hymenopteran insects and insects in general. He has also studied broader biological problems such as evolutionary theory, the principles of phylogenetics, taxonomy, nomenclature, and palaeoecology. He has published over 300 articles and books in several languages. In August 2008 he was awarded the Distinguished Research Medal of the International Society of Hymenopterists.

Haplodiploidy Biological system where sex is determined by the number of sets of chromosomes

Haplodiploidy is a sex-determination system in which males develop from unfertilized eggs and are haploid, and females develop from fertilized eggs and are diploid. Haplodiploidy is sometimes called arrhenotoky.

Parasitoid wasp

Parasitoid wasps are a large group of hymenopteran superfamilies, with all but the wood wasps (Orussoidea) being in the wasp-waisted Apocrita. As parasitoids, they lay their eggs on or in the bodies of other arthropods, sooner or later causing the death of these hosts. Different species specialise in hosts from different insect orders, most often Lepidoptera, though some select beetles, flies, or bugs; the spider wasps (Pompilidae) exclusively attack spiders.

Orussidae

The Orussidae or the parasitic wood wasps represent a small family of sawflies ("Symphyta"). Currently, about 85 extant and four fossil species are known. They take a key position in phylogenetic analyses of Hymenoptera, because they form the sister taxon of the megadiverse apocritan wasps, and the common ancestor of Orussidae + Apocrita invented parasitism for the first time in course of the evolution of the Hymenoptera. They are also the only sawflies with carnivorous larvae.

Xyelidae

The Xyelidae are a comparatively species-poor family of sawflies comprising about 80 extant species in five genera worldwide and is the only family in the superfamily Xyeloidea. The fossil record of the family is extensive, comprising more than 120 species and including the oldest fossil Hymenoptera species dating back to the Triassic, between 245 and 208 million years ago. Xyelidae are to be regarded as living fossils since they represent one of the oldest lineages of insects and include still extant forms.

Aculeata

Aculeata is a subclade of Hymenoptera. The name is a reference to the defining feature of the group, which is the modification of the ovipositor into a sting. In other words, the structure that was originally used to lay eggs is modified instead to deliver venom. Not all members of the group can sting; a great many cannot, either because the ovipositor is modified in a different manner, or because it is lost altogether. A large part of the clade is parasitic.

Stephanidae

The Stephanidae, sometimes called crown wasps, are a family of parasitoid wasps placed in the superfamily Stephanoidea, which has at least 345 living species in 11 genera. The family is considered cosmopolitan in distribution, with the highest species concentrations in subtropical and moderate climate zones. Stephanidae also contain four extinct genera described from both compression fossils and inclusions in amber.

Megalyridae

Megalyroidea is a small hymenopteran superfamily that includes a single family, Megalyridae, with eight extant genera and 49 described species. Modern megalyrids are found primarily in the southern hemisphere, though fossils have only been found in the northern hemisphere. The most abundant and species-rich megalyrid fauna is in Australia. Another peak of diversity appears to be in the relict forests of Madagascar, but most of these species are still undescribed.

<i>Bombus ternarius</i> Species of insect

Bombus ternarius, commonly known as the orange-belted bumblebee or tricolored bumblebee, is a yellow, orange and black bumblebee. It is a ground-nesting social insect whose colony cycle lasts only one season, common throughout the northeastern United States and much of Canada. The orange-belted bumblebee forages on Rubus, goldenrods, Vaccinium, and milkweeds found throughout the colony's range. Like many other members of the genus, Bombus ternarius exhibits complex social structure with a reproductive queen caste and a multitude of sister workers with labor such as foraging, nursing, and nest maintenance divided among the subordinates.

<i>Nasonia vitripennis</i>

Nasonia vitripennis is one of four known species under the genus Nasonia - small parasitoid wasps that afflict the larvae of parasitic carrion flies such as blowflies and flesh flies, which themselves are parasitic toward nestling birds. It is the best known and most widely studied of the parasitoid wasps, and their study forms a vital part of the information used to describe the order Hymenoptera, along with information from bees and ants. This parasitoid behaviour makes the wasps an interest for the development of biopesticide and biological systems for controlling unwanted insects.

Wasp Members of the order Hymenoptera which are not ants nor bees

A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps but are in a separate suborder. The wasps do not constitute a clade, a complete natural group with a single ancestor, as their common ancestor is shared by bees and ants. Many wasps, those in the clade Aculeata, can sting their insect prey.

Evolution of eusociality Origins of cooperative brood care, overlapping generations within a colony of adults, and a division of labor into reproductive and non-reproductive groups.

Eusociality evolved repeatedly in different orders of animals, particularly the Hymenoptera. This 'true sociality' in animals, in which sterile individuals work to further the reproductive success of others, is found in termites, ambrosia beetles, gall-dwelling aphids, thrips, marine sponge-dwelling shrimp, naked mole-rats, and the insect order Hymenoptera. The fact that eusociality has evolved so often in the Hymenoptera, but remains rare throughout the rest of the animal kingdom, has made its evolution a topic of debate among evolutionary biologists. Eusocial organisms at first appear to behave in stark contrast with simple interpretations of Darwinian evolution: passing on one's genes to the next generation, or fitness, is a central idea in evolutionary biology.

Worker policing Eusocial hymnopteran behavior where worker females destroy or remove eggs laid by other workers, in order to ensure that the queens offspring will be successful

Worker policing is a behavior seen in colonies of social hymenopterans whereby worker females eat or remove eggs that have been laid by other workers rather than those laid by a queen. Worker policing ensures that the offspring of the queen will predominate in the group. In certain species of bees, ants and wasps, workers or the queen may also act aggressively towards fertile workers. Worker policing has been suggested as a form of coercion to promote the evolution of altruistic behavior in eusocial insect societies.

Dufours gland

Dufour's gland is an abdominal gland of certain insects, part of the anatomy of the ovipositor or sting apparatus in female members of Apocrita. The diversification of Hymenoptera took place in the Cretaceous and the gland may have developed at about this time as it is present in all three groups of Apocrita, the wasps, bees and ants.

References

  1. Ronquist, Fredrik; Klopfstein, Seraina; Vilhelmsen, Lars; Schulmeister, Susanne; Murray, Debra L.; Rasnitsyn, Alexandr P. (December 2012). "A Total-Evidence Approach to Dating with Fossils, Applied to the Early Radiation of the Hymenoptera". Systematic Biology. 61 (6): 973–999. doi:10.1093/sysbio/sys058. PMC   3478566 . PMID   22723471.
  2. Mayhew, Peter J. (2007). "Why are there so many insect species? Perspectives from fossils and phylogenies". Biological Reviews. 82 (3): 425–454. doi:10.1111/j.1469-185X.2007.00018.x. PMID   17624962. S2CID   9356614.
  3. Janke, Axel; Klopfstein, Seraina; Vilhelmsen, Lars; Heraty, John M.; Sharkey, Michael; Ronquist, Fredrik (2013). "The Hymenopteran Tree of Life: Evidence from Protein-Coding Genes and Objectively Aligned Ribosomal Data". PLOS ONE. 8 (8): e69344. Bibcode:2013PLoSO...869344K. doi:10.1371/journal.pone.0069344. PMC   3732274 . PMID   23936325.
  4. 1 2 3 4 Aguiar, A.P.; Deans, A.R.; Engel, M.S.; Forshage, M.; Huber, J.T.; Jennings, J.T.; Johnson, N.F.; Lelej, A.S.; Longino, J.T.; Lohrmann, V.; Mikó, I.; Ohl, M.; Rasmussen, C.; Taeger, A.; Yu, D.S.K. (2013). "Order Hymenoptera Linnaeus, 1758. In: Zhang, Z.-Q. (Ed.) Animal Biodiversity: An Outline of Higher-level Classification and Survey of Taxonomic Richness (Addenda 2013)". Zootaxa. 3703: 1–82. doi:10.11646/zootaxa.3703.1.12. PMID   26146682.
  5. Grissell, Eric (2010). Bees, Wasps, and Ants: The Indispensable Role of Hymenoptera in Gardens . Timber Press.
  6. 1 2 Carpenter, George Herbert (1911). "Hymenoptera"  . In Chisholm, Hugh (ed.). Encyclopædia Britannica . 14 (11th ed.). Cambridge University Press. p. 177.
  7. Whiting, Michael F.; Whiting, Alison S.; Hastriter, Michael W.; Dittmar, Katharina (2008). "A molecular phylogeny of fleas (Insecta: Siphonaptera): origins and host associations". Cladistics. 24 (5): 677–707. CiteSeerX   10.1.1.731.5211 . doi:10.1111/j.1096-0031.2008.00211.x. S2CID   33808144.
  8. Yeates, David K.; Wiegmann, Brian. "Endopterygota Insects with complete metamorphosis". Tree of Life. Retrieved 24 May 2016.
  9. Whiting, Michael F. (2002). "Mecoptera is paraphyletic: multiple genes and phylogeny of Mecoptera and Siphonaptera". Zoologica Scripta. 31 (1): 93–104. doi:10.1046/j.0300-3256.2001.00095.x. S2CID   56100681. Archived from the original on 2013-01-05.
  10. Wiegmann, Brian; Yeates, David K. (2012). The Evolutionary Biology of Flies. Columbia University Press. p. 5. ISBN   978-0-231-50170-5.
  11. 1 2 3 4 5 6 Howell, H.V.; Doyen, J.T.; Purcell, A.H. (1998). Introduction to Insect Biology and Diversity (2nd ed.). Oxford University Press. p. 320. ISBN   978-0-19-510033-4.
  12. Peters, Ralph S.; Krogmann, Lars; Mayer, Christoph; Donath, Alexander; Gunkel, Simon; Meusemann, Karen; Kozlov, Alexey; Podsiadlowski, Lars; Petersen, Malte (April 2017). "Evolutionary History of the Hymenoptera". Current Biology. 27 (7): 1013–1018. doi: 10.1016/j.cub.2017.01.027 . PMID   28343967.
  13. Mao M, Gibson T, Dowton M (2014) Higher-level phylogeny of the Hymenoptera inferred from mitochondrial genomes. Mol Phylogenet Evol
  14. Schulmeister, S. (2003). "Simultaneous analysis of basal Hymenoptera (Insecta), introducing robust-choice sensitivity analysis". Biological Journal of the Linnean Society. 79 (2): 245–275. doi: 10.1046/j.1095-8312.2003.00233.x .
  15. Schulmeister, S. "Symphyta" . Retrieved 28 November 2016.
  16. Hunt, James H. (2007). The Evolution of Social Wasps. Oxford University Press, USA. p. 12. ISBN   978-0-19-804207-5.
  17. 1 2 David P. Cowan; Julie K. Stahlhut (13 July 2004). "Functionally reproductive diploid and haploid males in an inbreeding hymenopteran with complementary sex determination". PNAS. 101 (28): 10374–10379. Bibcode:2004PNAS..10110374C. doi:10.1073/pnas.0402481101. PMC   478579 . PMID   15232002.
  18. Elias, J.; Mazzi, D.; Dorn, S. (2009). Bilde, Trine (ed.). "No Need to Discriminate? Reproductive Diploid Males in a Parasitoid with Complementary Sex Determination". PLOS ONE. 4 (6): e6024. Bibcode:2009PLoSO...4.6024E. doi:10.1371/journal.pone.0006024. PMC   2696080 . PMID   19551142.
  19. Quiñones, Andrés E.; Pen, Ido (June 2017). "A unified model of Hymenopteran preadaptations that trigger the evolutionary transition to eusociality". Nature Communications. 8: 15920. Bibcode:2017NatCo...815920Q. doi:10.1038/ncomms15920. PMC   5490048 . PMID   28643786.
  20. Davies, N.R.; Krebs, J.R.; and West, S.A. An Introduction to Behavioral Ecology. 4th ed. West Sussex: Wiley-Blackwell, 2012. pp. 387–388
  21. LaSalle, John; David, Gauld, Ian (1993). Hymenoptera and biodiversity. C.A.B. International. ISBN   978-0851988306. OCLC   28576921.
  22. Pearcy, M.; Aron, S.; Doums, C.; Kelle, L. (2004). "Conditional use of sex and parthenogenesis for worker and queen production in ants" (PDF). Science. 306 (5702): 1780–3. Bibcode:2004Sci...306.1780P. doi:10.1126/science.1105453. PMID   15576621. S2CID   37558595.
  23. Oxley, P. R.; Ji, L.; Fetter-Pruneda, I.; McKenzie, S. K.; Li, C.; Hu, H.; Zhang, G.; Kronauer, D. J. (2014). "The genome of the clonal raider ant Cerapachys biroi". Curr. Biol. 24 (4): 451–8. doi:10.1016/j.cub.2014.01.018. PMC   3961065 . PMID   24508170.
  24. 1 2 Kellner, Katrin; Heinze, Jürgen (2011). "Mechanism of facultative parthenogenesis in the ant Platythyrea punctata". Evolutionary Ecology. 25: 77–89. doi:10.1007/s10682-010-9382-5. S2CID   24645055.
  25. 1 2 3 Rey, O.; Loiseau, A.; Facon, B.; Foucaud, J.; Orivel, J.; Cornuet, J. M.; Robert, S.; Dobigny, G.; Delabie, J. H.; Mariano Cdos, S.; Estoup, A. (2011). "Meiotic recombination dramatically decreased in thelytokous queens of the little fire ant and their sexually produced workers". Mol. Biol. Evol. 28 (9): 2591–601. doi: 10.1093/molbev/msr082 . PMID   21459760.
  26. 1 2 3 Baudry, E.; Kryger, P.; Allsopp, M.; Koeniger, N.; Vautrin D.; Mougel F.; Cornuet JM.; Solignac M. (2004). "Whole-genome scan in the lytokous-laying workers of the Cape honeybee (Apis mellifera capensis): central fusion, reduced recombination rates and centromere mapping using half-tetrad analysis". Genetics. 167 (1): 243–252. doi:10.1534/genetics.167.1.243. PMC   1470879 . PMID   15166151.
  27. Haag-Liautard C, Vitikainen E, Keller L, Sundström L (2009). "Fitness and the level of homozygosity in a social insect" (PDF). J. Evol. Biol. 22 (1): 134–142. doi:10.1111/j.1420-9101.2008.01635.x. PMID   19127611. S2CID   19566175.
  28. Lehnert, Matthew S.; Kramer, Valerie R.; Rawlins, John E.; Verdecia, Vanessa; Daniels, Jaret C. (2017-07-10). "Jamaica's Critically Endangered Butterfly: A Review of the Biology and Conservation Status of the Homerus Swallowtail (Papilio (Pterourus) homerus Fabricius)". Insects. 8 (3): 68. doi: 10.3390/insects8030068 . PMC   5620688 . PMID   28698508.

Bibliography

General
Systematics
Regional Lists
Books