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Platythyrea
''Platythyrea'' is a genus of predaceous ants in the subfamily Ponerinae and the sole member of the tribe Platythyreini. Distribution The genus has a worldwide distribution, and is found in the tropics and subtropics of the world. Description Workers are small to very large in size (4–20 mm). Gamergates (reproductive female workers) are known from all studied species except one, ''P. conradti'', which have ergatoid queens (wingless reproductive ants, intermediate in form between workers and winged queens). Some species with gamergates also have alate queens, which are similar to the workers but winged. Parthenogenesis Parthenogenesis is a natural form of reproduction in which growth and development of embryos occur without fertilisation. Thelytoky is a particular form of parthenogenesis in which the development of a female individual occurs from an unfertilized egg. Automixis is a form of thelytoky, but there are different kinds of automixis. The kind of automix ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platythyrea Bidentata
''Platythyrea'' is a genus of predaceous ants in the subfamily Ponerinae and the sole member of the tribe (biology), tribe Platythyreini. Distribution The genus has a worldwide distribution, and is found in the tropics and subtropics of the world. Description Workers are small to very large in size (4–20 mm). Gamergate (ant), Gamergates (reproductive female workers) are known from all studied species except one, ''P. conradti'', which have ergatoid queens (wingless reproductive ants, intermediate in form between workers and winged queens). Some species with gamergates also have alate queens, which are similar to the workers but winged. Parthenogenesis Parthenogenesis is a natural form of reproduction in which growth and development of embryos occur without fertilisation. Thelytoky is a particular form of parthenogenesis in which the development of a female individual occurs from an unfertilized egg. Automixis is a form of thelytoky, but there are different kinds of au ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platythyrea Bicuspis
''Platythyrea'' is a genus of predaceous ants in the subfamily Ponerinae and the sole member of the tribe Platythyreini. Distribution The genus has a worldwide distribution, and is found in the tropics and subtropics of the world. Description Workers are small to very large in size (4–20 mm). Gamergates (reproductive female workers) are known from all studied species except one, ''P. conradti'', which have ergatoid queens (wingless reproductive ants, intermediate in form between workers and winged queens). Some species with gamergates also have alate queens, which are similar to the workers but winged. Parthenogenesis Parthenogenesis is a natural form of reproduction in which growth and development of embryos occur without fertilisation. Thelytoky is a particular form of parthenogenesis in which the development of a female individual occurs from an unfertilized egg. Automixis is a form of thelytoky, but there are different kinds of automixis. The kind of automixi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platythyrea Arthuri
''Platythyrea'' is a genus of predaceous ants in the subfamily Ponerinae and the sole member of the tribe Platythyreini. Distribution The genus has a worldwide distribution, and is found in the tropics and subtropics of the world. Description Workers are small to very large in size (4–20 mm). Gamergates (reproductive female workers) are known from all studied species except one, ''P. conradti'', which have ergatoid queens (wingless reproductive ants, intermediate in form between workers and winged queens). Some species with gamergates also have alate queens, which are similar to the workers but winged. Parthenogenesis Parthenogenesis is a natural form of reproduction in which growth and development of embryos occur without fertilisation. Thelytoky is a particular form of parthenogenesis in which the development of a female individual occurs from an unfertilized egg. Automixis is a form of thelytoky, but there are different kinds of automixis. The kind of automixi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platythyrea Arnoldi
''Platythyrea'' is a genus of predaceous ants in the subfamily Ponerinae and the sole member of the tribe Platythyreini. Distribution The genus has a worldwide distribution, and is found in the tropics and subtropics of the world. Description Workers are small to very large in size (4–20 mm). Gamergates (reproductive female workers) are known from all studied species except one, ''P. conradti'', which have ergatoid queens (wingless reproductive ants, intermediate in form between workers and winged queens). Some species with gamergates also have alate queens, which are similar to the workers but winged. Parthenogenesis Parthenogenesis is a natural form of reproduction in which growth and development of embryos occur without fertilisation. Thelytoky is a particular form of parthenogenesis in which the development of a female individual occurs from an unfertilized egg. Automixis is a form of thelytoky, but there are different kinds of automixis. The kind of automixi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platythyrea Angusta
''Platythyrea'' is a genus of predaceous ants in the subfamily Ponerinae and the sole member of the tribe Platythyreini. Distribution The genus has a worldwide distribution, and is found in the tropics and subtropics of the world. Description Workers are small to very large in size (4–20 mm). Gamergates (reproductive female workers) are known from all studied species except one, ''P. conradti'', which have ergatoid queens (wingless reproductive ants, intermediate in form between workers and winged queens). Some species with gamergates also have alate queens, which are similar to the workers but winged. Parthenogenesis Parthenogenesis is a natural form of reproduction in which growth and development of embryos occur without fertilisation. Thelytoky is a particular form of parthenogenesis in which the development of a female individual occurs from an unfertilized egg. Automixis is a form of thelytoky, but there are different kinds of automixis. The kind of automixi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platythyrea Punctata
''Platythyrea punctata'' is a species of ant in the family Formicidae. References Further reading * Ponerinae Articles created by Qbugbot Insects described in 1858 {{ponerinae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hymenoptera
Hymenoptera is a large order (biology), order of insects, comprising the sawfly, 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 Parasitoid wasp, parasitic. Females typically have a special ovipositor for inserting eggs into hosts or places that are otherwise inaccessible. This ovipositor is often modified into a stinger. The young develop through holometabolism (complete metamorphosis (biology), metamorphosis)—that is, they have a wormlike 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. All references agree that the derivation involves the Ancient Greek language, Ancient Greek wikt:πτερόν, πτερόν (''pteron'') for wing. The Ancient Greek wikt:ὑμήν, ὑμήν (''hymen'') for membrane provides a plausible etymology for the term bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamergate (ant)
A gamergate ( ) is a mated worker ant that can reproduce sexually, i.e., lay fertilized eggs that will develop as females. In the vast majority of ant species, workers are sterile and gamergates are restricted to taxa where the workers have a functional sperm reservoir ('spermatheca'). In some species, gamergates reproduce in addition to winged queens (usually upon the death of the original foundress), while in other species the queen caste has been completely replaced by gamergates. In gamergate species, all workers in a colony have similar reproductive potentials, but as a result of physical interactions, a dominance hierarchy is formed and only one or a few top-ranking workers can mate (usually with foreign males) and produce eggs. Subsequently however, aggression is no longer needed as gamergates secrete chemical signals that inform the other workers of their reproductive status in the colony. Depending on the species, there can be one gamergate per colony (monogyny) or seve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thelytoky
Thelytoky (from the Greek ''thēlys'' "female" and ''tokos'' "birth") 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. Thelytoky can occur by different mechanisms, each of which has a different impact on the level of homozygosity. It is found in several groups of Hymenoptera, including Apidae, Aphelinidae, Cynipidae, Formicidae, Ichneumonidae, and Tenthredinidae. It can be induced in Hymenoptera by the bacteria ''Wolbachia'' and ''Cardinium''. Arrhenotoky and thelytoky in Hymenoptera Hymenoptera (ants, bees, wasps, and sawflies) have a haplodiploid sex-determination system. They produce haploid males ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ergatoid
An ergatoid (from Greek '' ergat-'', "worker" + ''-oid'', "like") is a permanently wingless reproductive adult ant or termite. The similar but somewhat ambiguous term ergatogyne refers to any intermediate form between workers and standard gynes. Ergatoid queens are distinct from other ergatogyne individuals in that they are morphologically consistent within a species and are always capable of mating, whereas inter caste individuals, another class of ergatogynes, often are not. Ergatoids can exhibit wide morphological differences between species, sometimes appearing almost identical to normal workers and other times being quite distinct from both workers and standard queens. In addition to morphological features, ergatoids among different species can exhibit a wide range of behaviors, with some ergatoids acting only as reproductives and others actively foraging. Ergatoid queens have developed among a large number of ant species, and their presence within colonies can often provide c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ponerinae
Ponerinae is a subfamily of ants in the Poneromorph subfamilies group, with about 1,600 species in 47 extant genera, including ''Dinoponera gigantea'' - one of the world's largest species of ant. Mated workers have replaced the queen as the functional egg-layers in several species of ponerine ants. In such queenless species, the reproductive status of workers can only be determined through ovarian dissections. Description and identification They are most easily identified from other subfamilies by possessing a single-node petiole with a constriction before the second gastral segment. They are rare examples of stinging ants. In addition to the sting, they can also be characterized by a single segmented petiole and the constriction of the first and second segment of the gaster. They can also be identified by the shape of their head. Female workers have twelve segmented antennae, whereas male workers have 13 segmented antennae. Behavior These ants typically nest in soil, for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fertilisation
Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a new individual organism or offspring and initiate its development. Processes such as insemination or pollination which happen before the fusion of gametes are also sometimes informally called fertilisation. The cycle of fertilisation and development of new individuals is called sexual reproduction. During double fertilisation in angiosperms the haploid male gamete combines with two haploid polar nuclei to form a triploid primary endosperm nucleus by the process of vegetative fertilisation. History In Antiquity, Aristotle conceived the formation of new individuals through fusion of male and female fluids, with form and function emerging gradually, in a mode called by him as epigenetic. In 1784, Spallanzani established the need of interaction between the female's ovum and male's sperm to form a zygote in frog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
