Parischnogaster mellyi | |
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Female from Peninsular Malaysia | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Hymenoptera |
Family: | Vespidae |
Genus: | Parischnogaster |
Species: | P. mellyi |
Binomial name | |
Parischnogaster mellyi (De Saussure, 1852) | |
Synonyms | |
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Parischnogaster mellyi is a medium-sized species of a hover wasp in the family Vespidae. It is found in Southeast Asia and is widely spread in Thailand and Malaysia. Its nests feature flexible and dynamic qualities, and they are commonly seen under roofs of houses and huts in rural areas. Hovering and patrolling behaviors are the species’ main defining behavioral features, and such activities are closely linked to its mating patterns.
All hover wasp species were placed under one genus, Stenogaster, until 1927, when von Schulthess created the new genus, Parischnogaster, for species populated in Asia. [1] Parischnogaster was synonymized with Holischnogaster by Carpenter in 1982, and it is possibly the largest and the least well known genus.
P. mellyi was first found by De Saussure in 1852. [1] Understanding of phylogenetic background for P. mellyi is of particular importance because “the independence of origin and range of social organization in the Stenogastrinae make it an important group for the study of evolution of social behavior in the family Vespidae." [1]
P. mellyi is considered a medium-sized wasp with an average length of 10mm. [1] Its head is sub-triangular shaped with uniform facial coloration. It also has a well developed Dufour’s gland, which seems accountable for abundant abdominal secretion that plays an important role in egg development (see colony cycle for more detail). [1] [2] There are a number of morphological differences between gender: in terms of exocrine glands, tegumental glands in males are clustered along the anterior portion of the third gastral tergum, and ectal mandibular glands are three times wider and longer than those of females. [1] Additionally, males have three white stripes on their tergites, while females do not carry such morphological features. [3] [4] There are no phenotypical differences between females of different social status. [4]
P. mellyi nests are known for their distinct combs at different levels of suspension. [5] It builds nests with materials from three main sources: vegetation close to the nest, materials stolen from abandoned or occupied neighboring nests, and material removed from one cell, which is then used to start to enlarge a cell in the other part of the nest. [5] Such recycling of the materials of the cells is frequently observed. A brand new cell is only built when there is no cell to shelter an anticipated egg. [5] Material used for nest development has two important features: the cuticular cell layer of plants constitutes a substantial portion of the nest, and the texture of the nest material is of fine crumbs and small flakes. [5] This kind of fragile aspect of the nest material might explain the low occurrence of large nests, and this may possibly hinder the evolution of large colony size. [1] [5] Its nesting structure is known for its flexibility, and thus lacks a typical shape or form. [5] First off, cells modify its size with the changing size of the larva as it grows: the cell goes through a phase of regression until the cell size is equivalent to that of the growing larva. [5] Then, both the larva and the cell starts to grow again in a similar fashion. Additionally, there is a general trend of decrease percent cell wall sharing with increase in suspension length. [5] Typically, the nests are located on the strands of dead vegetation such as hanging vine tendrils or loose strands of thatch under the roofs of houses. The mean total suspension length of these nests is 18.4 cm and the mean suspension width is 0.64mm. [5] The long and narrow shape of the nest also provides protection from predators. [5]
P. mellyi has been identified in Thailand and Malaysia, and it is commonly found near forest edge habitats. [1] [5] It often constructs its nests under the roofs of thatched huts and houses in rural areas. [5] [6] Such habitat choice is unique to P. mellyi, since Stenogastrinae species population is rarely found in places disturbed by human contact and civilization. [5]
All colonies of P. mellyi are founded by a single female and expand with the emergence of sons and daughters. [2] [5] [6] The typical colony size is one female (i.e. no male), and it rarely exceeds three females, while the maximum number of males present in a nest is four. Nests are actively defended against strange females approaching or landing on a nest. Median survival time of a typical colony is 47 days, and the longest surviving nest is recorded to be 237 days before it died out. [6]
The average length of P. mellyi developmental period is around 53 days. [2] The three developmental stages are: egg phase (a one-day period between egg laying to hatching, where the egg is placed with the mouthparts), larval phase (approximately a 25.71-day period between egg laying to pupation), and pupal phase (a 17.8-day period between the capping of the cell and the emergence of the adult). White sticky abdominal droplets are secreted from Dufour’s gland during egg laying. [2] These droplets play an important role in development stages, since in the form of these white abdominal secretions do the eggs receive attention from adult females. [2] However, wasps of P. mellyi produce less rich secretions from their Dufour's glands than wasps of P. jacobsoni , and thus do not produce ant guards using this secretion. [7]
Hatching ratio of genders is approximately one-to-one, and average brood size in a one-female nest is 4.68. Additionally, a positive correlation between brood size and the number of males present in a nest attests to the trend that males are more likely to be populated in bigger nests. [2] [6]
Elementary behaviors described in this section pertain to principal behavioral activities that are common to both adult males and females in a given colony. [1]
While social stratification does not attribute to clean-cut morphological differences, there is behavioral variability that categorizes different social roles that the females can play. [4] While top-dominant females, often called ‘senior-females,’ rarely leave the nest and usually monopolize oviposition, the lower-ranked, worker females engage in more foraging behavior. [4] [6] It has been observed that an individual female P. mellyi has three behavioral options that determines its position on the hierarchy (and thus its future life and “fitness acquisition”): it can either leave the natal colony and found its own colonies (P. mellyi nests are found by single foundresses) or wait on the natal nest to succeed the dominant female role when nests are abandoned (or at times, actively attempt to dethrone her). If this scenario were to happen, the new dominant female would continue rearing those left by the prior occupants. This often leads to continuous formation of stepmother-stepdaughter associations in most nests. Lastly, it can just accept the role of a worker and take care after a number of individuals that are genetically related to themselves. [1] [6]
One of the behavioral characteristics of Parischnogaster species is its frequent patrolling activity and is extensively found in P. mellyi and P. nigricans serrei . When a male P. mellyi engages in a hovering activity, it usually faces towards the center of a vegetation nearby. [1] It remains to hover for a number of seconds, and then turns around to make a long roundabout, typically horizontally to the left and right. Afterwards, it returns to the original "landmark". When hovering around the landmark, P. mellyi typically extends and contracts its gaster (posterior abdominal region) to display the three white stripes on its tergites. Seven main patrolling behaviors for when the males are in flight have been identified: [1] [3]
Patrolling flights usually take place at certain, well-defined hours of the day. In the West Java region, it has been recorded that P. mellyi leave their nests around 11:00am and return around 12:45pm. [1]
Mating activity of P. mellyi is interrelated to its patrolling behavior. An observation study has shown that a male is typically active for 3 weeks or more (up to 32 days), rarely lands while hovering (but does so more frequently towards the end of a patrolling session by walking along the edges of leaves nearby), and feeds themselves at food sources at the end of activity and returns to its nests or communal resting points. [3] In contrast, female P. mellyi appears at patrolling landmarks around the second hour of male activity to engage in sexual interactions. [1] [3] In a typical sexual intercourse, the female approaches the male from the back, lengthening her legs towards his gaster, while the male extends the aerial display, often moving in a zigzag pattern. At this point in time, the female lands on the hover site and repeatedly touches the surface of the site with the tip of her gaster. The male then quickly touches the female’s back with his legs, grabs her chest for a few seconds, and establishes a genital connection for about 2–25 seconds. After the intercourse, the female will clear her genital area with her legs. [1] [3]
When it comes to mating selection, females prefer males who exhibit endurance. By scoring endurance (measured in flight/ patrol time), females can gather reliable and valid information on a male’s quality. A female’s preference towards long-term patrollers could potentially help explain the prolonged male lekking behavior. [3]
Male P. mellyi attempts in homosexual mating have also been observed in a number of captivity studies. [1]
The characteristic three white stripes on the abdomen of male P. mellyi plays an important role in determining wasp behavior in both intra- and intersexual contexts of the species; the armament-ornament model proposes that the presence of ornaments (in this case, the active display of three white stripes) to be seen as a status badge that is used for both male-to-male competition and courtships for future mates. [3] [9] During patrol activity over its hover sites, male P. mellyi openly displays its three white stripes on its tergites by fully distending its abdomen. [9] A positive correlation has been found between elicited stripe display and mating success: male individuals who displayed their stripes the most, not simply the most active ones, were the individuals who had the highest chance of mating with females. [6] This kind of mating success via the stripes display, however, comes with a cost: According to a stripe manipulation study, when an extra stripe was added, the frequency of the attacks received by the male rival had doubled. [3] In fact, winner males of aerial duels frequently displayed their stripes. Therefore, while stripes were indicators of strength in aerial duels, this sort of status badge was also attractive to females, as predicted by the Armament-Ornament Model. [3]
It has been observed in Thailand that the Greater banded hornet, Vespa tropica, often preys on colonies of P. mellyi. Damages caused by raids from this hornet can be characterized by gaping holes that are torn out on the sides of the cells. [1]
In some Vespidae species, volatiles in their venom secretion have been found to play a pheromonal role. [1] In particular species, venom seems to function as an alarm for warning the presence of predators in the vicinity. [1] Volatile fraction of P. mellyi venom contains some spiroacetals, which in Polistes and Vespa species seems to serve as a function of alarm pheromones. Previous behavioral bioassays conducted 14 years ago showed no positive correlation between the venom of the Stenogastrinae species and the function of alarm pheromones. However, future investigation seems necessary to establish a clear conclusion on the specific role of P. mellyi venom. [1]
The European paper wasp is one of the most common and well-known species of social wasps in the genus Polistes. Its diet is more diverse than those of most Polistes species—many genera of insects versus mainly caterpillars in other Polistes—giving it superior survivability compared to other wasp species during a shortage of resources.
Polistes gallicus is a species of paper wasp found in various parts of Europe, excluding England, Denmark, and Scandinavia, from warmer climates to cooler regions north of the Alps. Nests of these social insects are created in these various conditions. The Polistes species use an oral secretion to construct their nests, which consist of a combination of saliva and chewed plant fibers. This structural mixture physically protects the nest from various harsh elements and from weathering over time.
The Stenogastrinae are a subfamily of social wasps included in the family Vespidae. They are sometimes called hover wasps owing to the particular hovering flight of some species. Their morphology and biology present interesting peculiarities.
Polistes humilis, known as the Australian paper wasp, is a species of wasp in the Vespidae family that is found throughout Australia and which has been introduced to northern New Zealand. These paper wasps can be identified by their long thin legs and banded yellow and black coloring. They have been known to re-utilize old nests. While the species does not exhibit morphological class differences, there are distinct behavioral differences between queens and workers. In addition, the species is eusocial and benefits from relatedness between individuals. They are known for delivering a painful sting, especially when their nest is disturbed, a behavior that has been developed as a nest defense mechanism. While wasps are often viewed negatively, they play an important pollination role for many plants.
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.
Belonogaster juncea juncea is a subspecies of Belonogaster juncea and is classified as a primitively eusocial wasp, meaning that the species is social while exhibiting a morphology that is indistinguishable from that of other castes. It is also classified as a type of African Paper Wasp. Many of the studies relating specifically to B. j. juncea take place at the University of Yaoundé in Cameroon.
Polistes nimpha is a eusocial paper wasp found all over Europe, with particular sightings in Turkey, Finland, Estonia, and Latvia. It is also found in northern Africa, Pakistan, Iran, India, Kazakhstan, Mongolia, and China. The climate in these areas is relatively cold and snowy in the winter, while summers are usually hot and dry, with steppe vegetation. Polistes nimpha colonies are relatively small and easily manipulated.
Polistes canadensis is a species of red paper wasp found in the Neotropical realm. It is a primitively eusocial wasp as a member of the subfamily Polistinae. A largely predatory species, it hunts for caterpillar meat to supply its colony, often supplementing its developing larvae with nectar. The most widely distributed American species of the genus Polistes, it colonises multiple combs, which it rears year-round.
Liostenogaster flavolineata is an insect that belongs to the wasp family Vespidae. This hairy-faced hover wasp species is predominantly found in South Asian rain forests, especially in Malaysia. Individual colonies of this species are very small, but aggregations of nests allow for interactions between many smaller colonies. Some worker wasps, known as "helpers", will move between multiple nests in an attempt to improve their position in the dominance hierarchy. Its nests are pale-colored and are usually built with mud. Liostenogaster flavolineata is one of the most studied species in the Stenogastrinae.
Ropalidia revolutionalis, the stick-nest brown paper wasp, is a diurnal social wasp of the family Vespidae. They are known for the distinctive combs they make for their nests, and they are mostly found in Queensland, Australia in the areas of Brisbane and Townsville. They are an independent founding wasp species, and they build new nests each spring. They can be helpful because they control insect pests in gardens.
The Black hover wasp, Parischnogaster alternata, is a eusocial wasp in the genus Parischnogaster. It is native to South-East Asia, and builds its nests in cavities located in dark and damp locations. The nests of Black hover wasps are often found in clusters, which serves as a passive defense mechanism against predators. The annual colony cycle begins with nest initiation by a single foundress though colonies typically consist of 2-3 associative females and helpers that aid in brood development, nest construction, and colony defense. Indicative of the name, female P. alternata are known to strategically hover near nests when visiting other colonies before landing. These intrusions produce responses ranging from aerial fighting to cooperative food sharing.
Parischnogaster nigricans serrei is a hover wasp subspecies in the family Vespidae, and it is predominantly found in the Java region of Indonesia. Its nest cells are of conical structure, linearly attached to a string-like substratum. The nests are typically found in places open to human interactions, such as gardens, trees, or forests around villages. There is a clear dominance hierarchy within colonies, which often affects the behavioral activities of its members. The wasp’s most common predators are Vespa tropica, also known as the great banded hornet. P. nigricans serrei defends itself by flying away or giving out alarm calls.
Polybioides raphigastra is a species of social wasp found in the forests of South East Asia and Indonesia. It has recently been placed in the tribe Ropalidiini. This species is known for the downward-spiraling shape of their nests, and for having colony sizes exceeding ten thousand members.
Mischocyttarus flavitarsis is a social paper wasp found in western North America. Their nests can be found both in forests close to rivers or in close proximity to human life under the eaves of roofs. Despite the fact that M. flavitarsis nests are frequently in close contact with humans, M. flavitarsis typically will not sting, but rather ram into the threatening individual. Their colony cycle typically begins before May and will last until October. The queen will then seek a hibernation site for the winter. Perched near female hibernation sites are males with whom the female will mate. The males have claimed their territory by rubbing sternal brushes along the border of the site, leaving a chemical that deters other individuals from approaching. M. flavitarsis feed on arthropods, nectar, and animal carcasses and are often prey to birds, ants, and praying mantis.
Parischnogaster striatula is a species of social hover wasps found in Southeast Asia. Their nests are uniquely shaped, mimic their surroundings and, like the other Stenogastrinae social wasps, lack a nest pedicel. They are also unique in their use of glandular secretion when laying eggs. P. striatula is also different than typical wasps because the queens are not the only ones who possess reproductive capabilities; other females also have developed ovaries. This wasp is also known for fiercely protecting its nest against enemies, such as ants or other hornets.
Liostenogaster vechti is a type of eusocial hover wasp within the family Vespidae. They are typically brown and yellow in color and are considered a passive aggressive species. Their stings are less painful to humans than other social wasps, and they engage in associative nest foundation. They are mostly found on the Malaysian peninsula and are known for living in large clusters of small ring-shaped nests.
Parischnogaster jacobsoni is a species of social wasp within Parischnogaster, the largest and least known genus of Stenogastrinae. It is distinguished mainly by its tendency to construct ant guards on its nests. Natural selection has led this wasp to have a thick substance emitted from its abdominal glands that allows it to protect its nest from invasions. Parischnogaster as a genus has been relatively unstudied; P. jacobsoni is one of the few investigated species because it has sufficient durability to live near human populations and it has demonstrated unusual resilience to pollution. While P. jacobsoni is a more complex organism than other wasps in Parischnogaster, the genus overall is relatively primitive with respect to social wasps as a whole.
Mischocyttarus mexicanus cubicola is a neotropical paper wasp found in the New World. It is a social wasp that demonstrates two different types of nesting strategies, depending upon context. This context-dependent trait makes Mischocyttarus mexicanus cubicola a good model to study social biology within social wasps. In detail, this trait allows for the females of this species to form nests both individually and as co-founders with other females within the same colony. This subspecies is also known to exhibit cannibalism, with M. m. cubicola queens feeding on their own larvae for nourishment when unaided by workers.
Parischnogaster is a genus of hover wasps from the subfamily Stenogastrinae, a subfamily of eusocial wasps endemic to the Oriental Region which are included in the family Vespidae.
Vespula infernalis is an obligate parasitic wasp, parasitizing the nests of other species in the genus Vespula. Its common host species is V. acadica in North America. It is sometimes called the cuckoo yellowjacket wasp due to its inquiline lifestyle. They differ from other parasitic wasps in their intensely aggressive behaviour during invasion and occupation of the host colony. Several morphological adaptations such as bigger body parts and more curved sting shafts are observed in these wasps to aid their aggressive parasitic behaviour. Once they occupy a host's nest, V. infernalis are known to engage in mauling and chasing of host workers and forced trophallaxis. Female wasps will also force host workers to feed and take care of their brood.
Video clips of various Parischnogaster mellyi behaviors: