Unlikely wasp enemy of a serious alien pest in North America named Idris elba

A new species of wasp discovered in Mexico and named Idris elba, could help in managing the serious non-native bagrada bug, which already damages vegetable crops across North America.

While a mention of the British movie and music star is missing in its description, the species might prove to be a Heimdall-like ‘protector’ for many crops

A parasitic wasp was recently discovered in Guanajuato, Mexico, where it was found to parasitize the eggs of an invasive stink bug, known as the bagrada bug, which is a major pest of cruciferous vegetables. A research team from Colegio de Postgraduados (Mexico)Agriculture and Agri-Food Canada (AAFC) and the Florida State Collection of Arthropods (FSCA) collaborated to publish a study on the biology this species, Idris elba, and describe it as a species new to science.

The genus Idris was described in 1856 and now contains over 300 species and many more species are still undescribed. Species of Idris were previously known to only parasitize spider eggs. It was thus very unexpected when specimens of Idris were found to emerge from eggs of the bagrada bug by Dr. Refugio Lomeli-Flores and his team in Guanajuato. Advanced methods in molecular forensics were used by Dr. Tara Gariepy (AAFC) to match the DNA of the adult wasp with DNA left behind in the stink bug egg from which it emerged, independently confirming the results. The specimens were then sent to taxonomist, Dr. Elijah Talamas (FSCA), who determined that it was an undescribed species.

The discovery of this wasp marks an important step toward the development of efficient and natural control of the stink bug species Bagrada hilaris in North America. Commonly known as the bagrada bug, it is native to Africa, but is already an established and important pest of over 74 plant species in India, southern Europe, southern Asia and the Middle East.

Аcross the Atlantic, it has been known since 2008, when it was reported from Los Angeles, California (USA), followed by records from Coahuila state, Mexico, in 2014. Three years later, it was also found in the state of Guanajuato, which is responsible for over 70% of the country’s broccoli production, as well as the major import of broccoli and cauliflower in the USA and Canada. So far, measures to halt the bug’s invasion have proven largely ineffective, and its distribution is expected to reach new ecosystems of economical importance.

Non-parasitized (left) compared with a parasitized (right) bagrada bug egg, where an
Idris elba wasp was observed to emerge.
Image by Elijah J. Talamas

While not unheard of, it is uncommon for native parasitoids to attack an introduced host. Idris elba is exceptional because it demonstrates that these wasps can make the leap from parasitizing the eggs of spiders to the eggs of stink bugs. Having rejected the possibility of the species having been introduced alongside its host, the scientists note that the unexpected association could be either the result of a broad host range, or a case of lucky confusion, where the parasitoid tends to mistake the eggs of the stink bug for those of a spider.

It is no coincidence that this wasp has the species name “elba”. Dr. Talamas explained that explicitly naming the species after Idris Elba (the actor), also known as a patronym, would have to follow Latin grammar and become Idris elbai. By treating the second name as an arbitrary combination of letters, the grammar was avoided.

Four-time Golden Globe nominee for Best Actor, Idris Elba is a famous British actor, producer, writer, singer, DJ and producer, best known for a long list of blockbusters, including a good number of superhero movies, such as the Marvel series inspired by the myths of the Norse god Thor. There, Elba stars as Heimdall, whose almost namesake: Heimdallr, is a Norse deity believed to be the sole protector of the bridge linking the human world and the realm of the gods.

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Original source:

Lomeli-Flores JR, Rodríguez-Rodríguez SE, Rodríguez-Levya E, González-Hernández H, Gariepy TD, Talamas EJ (2019) Field studies and molecular forensics identify a new association: Idris elba (Talamas), sp. nov. parasitizes the eggs of Bagrada hilaris (Burmeister). In: Talamas E (Eds) Advances in the Systematics of Platygastroidea II. Journal of Hymenoptera Research 73: 125-141. https://doi.org/10.3897/jhr.73.38025

Stuck in a Polish nuclear weapons bunker cannibal wood ants find the way home

In a recent development of the story about wood ants trapped in a post-Soviet nuclear weapons bunker in Poland, scientists, led by Prof. Wojciech Czechowski, with the decisive contribution of Dr. István Maák, both from the Museum and Institute of Zoology, Polish Academy of Sciences in Warsaw, deduced that the “colony” (in quotation marks because only workers were found), while lacking other food, had to survive on the corpses of imprisoned nestmates. By using an experimentally installed boardwalk, the ants were helped to get through the ventilation pipe that led out of the bunker and back to their maternal nest on the top.

The ants were discovered in 2013 thanks to a yearly campaign set to count hibernating bats in the same bunker. The scientific report was published in 2016 also in Journal of Hymenoptera Research. At that time, the scientists estimated the presence of at least several hundred thousand workers, arguably close to a million. The insects ended up in this situation as a result of large numbers of wood ants continuously falling down a ventilation pipe to never return to their nest on top of the bunker. Several years later, the “colony” still appeared to be thriving, despite being trapped in a confined space with no light, heat and obvious source of food.

In the newly published paper, the scientists sought out whether while lacking alternative food, the wood ants would consume the dead bodies of their conspecifics that were accumulating on the bunker floor. In nature, a similar behaviour occurs frequently during spring, when protein food is scarce. These are the so-called “ant wars”, which serve to set the boundaries of the territories of neighbouring conspecific colonies of wood ants, while simultaneously providing food in the form of the fresh corpses of the numerous victims.

Recent research has also shown that corpse consumption in wood ants is more common than it was previously thought, and that nestmate’s corpses can serve as an important food source not only in periods of food shortage.

Taking into account the clear signs of cannibalism in the bunker with practically no other organisms to feed on the ant cadavers, the scientists could safely deduce that the bunker “colony” survived indeed on consuming mostly dead nestmates.


“The present case adds a dimension to the great adaptive ability of ants to marginal habitats and suboptimal conditions, as the key to understanding their unquestionable eco-evolutionary success”, added the authors.


In the spring of 2016, the scientists decided to free the captive ants. At first, they released a group of one hundred ants from the bunker into the outskirts of the mother nest, in order to confirm the relation between the two partly isolated groups. As expected, no aggressive behaviour was observed. In September, a 3-metre-long vertical boardwalk with one end burrowed in the mound made by the bunker “colony” and the other one tucked inside the ventilation pipe was constructed. Soon, individual ants started to inspect the escape route. By February 2017, the nuclear weapon bunker was almost deserted. Meanwhile, the maternal wood ant colony still nests at the top of the bunker at the outlet of the ventilation pipe, and ants continue to fall down through the pipe. However, the boardwalk now allows them to move freely up and down.


“So, we can expect further intriguing ant behaviour,” comment the scientists.

Non-native pest-controlling wasp identified in Canada prior to formal approval

A samurai wasp (Trissolcus japonicus) lays an egg inside a brown marmorated stink bug (Halyomorpha halys) egg. The samurai wasp’s offspring will develop inside the pest’s egg and emerge as an adult wasp. Photo by Warren Wong.

Thought to be Canada’s most promising potential defense against the brown marmorated stink bug – a globally spreading agricultural pest native to Asia – the samurai wasp (another species from Asia and natural parasitoid of the former) has been considered for future release in the country in recent years.

However, prior to any formal decision and regulatory approval, the parasitoid, which is known to be specialized on stink bug eggs, was identified at a heavily infested site in Chilliwack, British Columbia, during a survey of the local enemies of the bug, conducted by a research team led by Dr. Paul Abram of Agriculture and Agri-Food Canada. Their findings are published in the open-access Journal of Hymenoptera Research.

Native to China, Japan, Taiwan and the Korean peninsula, the brown marmorated stink bug (Halyomorpha halys) has already established in areas of the United States and Europe and continues to spread. It is highly damaging to a wide range of vegetable and fruit crops, including peaches, apples, pears, soybeans, cherries, raspberries and pears. Curiously, those infested areas in both the USA and Europe also saw the arrival of the samurai wasp (Trissolcus japonicus) amid assessments whether releasing samurai wasps in the wild should be warranted.

“Classical (importation) biological control of invasive pests, where natural enemies are imported and intentionally introduced from a pest’s area of origin, involves years of research to assess risks and benefits of proposed introductions, followed by regulatory approval,” explain the researchers in their paper.

“However, there is increasing recognition that unintentional introductions of natural enemies are probably common, introducing a high level of uncertainty to the regulatory process for biological control introductions.”

In two consecutive years (2017 and 2018), the team of Dr Abram placed a total of 1,496 egg masses (41,351 eggs) of brown marmorated stink bugs at 16 field sites in coastal and interior British Columbia – already known to host large and well-established breeding populations of the species – in order to monitor and identify the local enemies of the pest. Later on, when the researchers retrieved the eggs and studied their parasitoids, they found three native wasp species, but their parasitism appeared largely unsuccessful.

Female samurai wasp (Trissolcus japonicus) collected from Chilliwack, British Columbia. Photo by Elijah Talamas.

According to the scientists, as well as previous studies conducted in both the USA and Europe, native wasps would often lay their eggs in those of the brown marmorated stink bug, but their larvae would rarely complete development. Even when they emerged, they were unlikely to produce their own offspring.

In one of the egg masses, however, the scientists noted that all eggs had been parasitized and, moreover, each produced a viable wasp. Later, the offspring would register a success of >90% in parasitizing brown marmorated stink bug eggs. Following these observations, the team identified these parasitoids as samurai wasps.

While the species is currently being redistributed within some US states on purpose, samurai wasp populations advancing to other localities suggest that much like its host, the parasitoid is also becoming a “global invader”. Therefore, it is quite possible that the samurai wasps in British Columbia have simply crossed a distance of >400 km from nearby Washington State, and the wasp is still at the early stages of its establishment in Canada.

“Nonetheless, the detection of this exotic biological control agent in Canada concurrently with regulatory review of its intentional importation and release is emblematic of the current uncertainty around regulatory control on the movement of biological control agents across borders,” comment the authors of the study.

Field surveys and extensive analyses are currently underway to track the establishment and biological control impact of the samurai wasp in Canada and also reveal how the species ended up in British Columbia.

 

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Original source:

Abram PK, Talamas EJ, Acheampong S, Mason PG, Gariepy TD (2019) First detection of the samurai wasp, Trissolcus japonicus (Ashmead) (Hymenoptera, Scelionidae), in Canada. Journal of Hymenoptera Research 68: 29-36. https://doi.org/10.3897/jhr.68.32203

Bee diversity and richness decline as anthropogenic activity increases, confirm scientists

The researchers compared wild bee communities in the tropical dry forest of Mexico living in three habitat conditions: preserved vegetation, agricultural sites and urbanised areas

Changes in land use negatively affect bee species richness and diversity, and cause major shifts in species composition, reports a recent study of native wild bees, conducted at the Sierra de Quila Flora and Fauna Protection Area and its influence zone in Mexico.

Having registered a total of 14,054 individual bees representing 160 species, 52 genera, and five families over the span of a year, the scientists conclude that the studied preserved areas demonstrated “significantly greater” richness and diversity.

In their paper, published in the open-access Journal of Hymenoptera Research, a research team from the University of Guadalajara, Mexico, led by Alejandro Muñoz-Urias, compare three conditions within the tropical dry forest study site: preserved vegetation, an agricultural area with crops and livestock, and an urbanised area.

This bee species (Aztecanthidium xochipillium) is known exclusively from Mexico.

The researchers confirm earlier information that an increase in anthropogenic disturbances leads to a decrease in bee richness and diversity. While availability of food and nesting sites are the key factors for bee communities, changes in land use negatively impact flower richness and floral diversity. Thereby, turning habitats into urbanised or agricultural sites significantly diminishes the populations of the bees which rely on specific plants for nectar and pollen. These are the species whose populations are threatened with severe declines up to the point of local extinction.

According to their data, about half of the bees recorded were Western honey bees (49.9%), whereas polyester bees turned out to be the least abundant (1.2 %).

On the other hand, some generalist bees, which feed on a wide range of plants, seem to thrive in urbanised areas, as they take advantage of people watering wild and ornamental plants at times where draughts might be eradicating native vegetation.

“That is the reason why bees that can use a wide variety of resources are often able to compensate when circumstances change, although some species disappear due to land use changes,” explain the scientists.

This is a tropical dry forest in the dry (left) and rainy season (right).

In conclusion, the authors recommend that the tropical dry forests of both the study area and Mexico in general need to be protected in order for these essential pollinators to be conserved.

“Pollinators are a key component for global biodiversity, because they assist in the sexual reproduction of many plant species and play a crucial role in maintaining terrestrial ecosystems and food security for human beings,” they remind.

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Original source:

Razo-León AE, Vásquez-Bolaños M, Muñoz-Urias A, Huerta-Martínez FM (2018) Changes in bee community structure (Hymenoptera, Apoidea) under three different land-use conditions. Journal of Hymenoptera Research 66: 23-38. https://doi.org/10.3897/jhr.66.27367

Towards untangling the ‘antennal grabbing’ phenomenon in mating cuckoo bees

Scientists report this behavior for the first time in the genus Nomada, following both lab and field observations in Germany

One can seldom spot a cuckoo bee, whose peculiar kleptoparasitic behaviour includes laying eggs in the nests of a certain host bee species, let alone a couple mating.

Nevertheless, German scientists – Dr. Matthias Schindler, University of Bonn, Michaela Hofmann and Dr. Susanne S. Renner of the University of Munich, and Dr. Dieter Wittmann, recently managed to record copulation in three different cuckoo bee species in the genus Nomada.

Intriguingly, in field and lab settings alike, the observed couples demonstrated the phenomenon the researchers called “antennal grabbing” where the male cuckoo bee winds his antennae around

Insertion phase of copulation in a couple of the species Nomada flavoguttata. Note the male’s antennae spirally entangling the female’s.

the female’s during copulation, thus transferring pheromones. Even though such behaviour is relatively common in Hymenoptera, this is the first known record for the genus Nomada.

While the particular biological reason for the “antennal grabbing” in different species remains unsettled, the scientists discuss the phenomenon in view of both previous hypotheses and their own observations in a new paper published in the open access Journal of Hymenoptera Research.

The courtship in Nomada cuckoo bee starts with the ‘swarming’ of males at willow shrubs and gooseberry or their patrolling in groups with males of the Andrena or Melitta species that will “foster” their offspring.

Two males of the species Nomada flavoguttata patrolling at a blossom of a common dandelion.

There is no aggression among the males. They were observed to rub their bellies and heads against the grass, in order to leave sexual pheromones, thus marking the “dating spot” for potential mates.

Earlier chemical studies of Nomada bees noted that the mandibular glands of males produce chemical compounds identical with those of their Andrena or Melitta hosts, leading to the suggestion that the males transfer pheromones that help the females mimic the odor of the host bee, and later enter its nest unnoticed to lay its eggs. An alternative explanation for the “antennal grabbing” is that males are spraying a substance onto the females to make them unattractive to other potential mates.

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Original source:

Schindler M, Hofmann MM, Wittmann D, Renner SS (2018) Courtship behaviour in the genus Nomada – antennal grabbing and possible transfer of male secretions. Journal of Hymenoptera Research 65: 47-59. https://doi.org/10.3897/jhr.65.24947

Journal of Hymenoptera Research links Crocodile Dundee, Toblerone, Game of Thrones & Alien

A myriad of species and genera new to science, including economically important wasps drawing immediate attention because of their amusing names and remarkable physical characters, in addition to work set to lay the foundations for future taxonomic and conservation research, together comprise the latest 64th issue of Journal of Hymenoptera Research (JHR).

The species Qrocodiledundee outbackense

Two genera (Qrocodiledundee and Tobleronius) named after the action comedy Crocodile Dundee and the chocolate brand Toblerone are only a couple of the 14 new genera from the monograph of the microgastrine wasps of the world’s tropical regions, authored by Dr Jose Fernandez-Triana and Caroline Boudreault of the Canadian National Collection of insects in Ottawa. In their article, the team also describes a total of 29 new species, where five of them carry the names of institutions holding some of the most outstanding wasp collections.

Another curiously named species of microgastrine wasp described in the new JHR issue, is called Eadya daenerys in reference to Daenerys Targaryen, a fictional character known from the best-selling book series A Song of Ice and Fire by George R. R. Martin, and the blockbuster TV show Game of Thrones. Discovered by University of Central Florida‘s Ryan Ridenbaugh, Erin Barbeau and Dr Barbara Sharanowski as a result of a collaboration between biocontrol researchers and taxonomists, the new species might not be in control of three dragons, nor a ruler or protector of whole nations. However, by being a potential biocontrol agent against a particular group of leaf beetle pests, it could spare the lives of many eucalyptus plantations around the world.

The species Tobleronius orientalis

Furthermore, a wasp named Dolichogenidea xenomorph, which parasitises other eucalyptus pests, is also named after a character from a sought-after franchise. The scriptwriters of the horror sci-fi movie series Alien are thought to have been thinking of parasitic wasps when they came up with the character Xenomorph, remind authors Erinn Fagan-Jeffries, Dr Steven Cooper and Dr Andrew Austin. Additionally, the team from University of Adelaide and the South Australian Museum point out that the species name translates to ‘strange form’ in Greek, which perfectly suits the characteristic remarkably long ovipositor of the new wasp.

The species Eadya daenerys

In another paper of the same journal issue, Dr. Jean-Luc Boevé, Royal Belgian Institute of Natural Sciences, Diego Domínguez, Universidad Técnica Particular de Loja, Ecuador, and Dr David Smith, Smithsonian’s National Museum of Natural History, USA, publish an illustrated list of the wasp-related sawflies, which they collected from northern Ecuador a few years ago. They also provide a checklist of the country’s species.

In conclusion, the fifth paper, authored by Serbian scientists Dr Milana Mitrovic Institute for Plant Protection and Environment, and Prof Zeljko

The species Dolichogenidea xenomorph

Tomanovic, University of Belgrade, studies ways to extract DNA from dry parasitoid wasps from the natural history archives decades after their preservation. In their work, they make it clear that such projects are of great importance for future taxonomic and conservation research, as well as agriculture.

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The open access Journal of Hymenoptera Research is published bimonthly by the scholarly publisher Pensoft on behalf of the International Society of Hymenopterists.

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Original sources:

Boeve; J, Dominguez D, Smith D (2018) Sawflies from northern Ecuador and a checklist for the country (Hymenoptera: Argidae, Orussidae, Pergidae, Tenthredinidae, Xiphydriidae). Journal of Hymenoptera Research 64: 1-24. https://doi.org/10.3897/jhr.64.24408

Ridenbaugh RD, Barbeau E, Sharanowski BJ (2018) Description of four new species of Eadya (Hymenoptera, Braconidae), parasitoids of the Eucalyptus Tortoise Beetle (Paropsis charybdis) and other Eucalyptus defoliating leaf beetles. Journal of Hymenoptera Research 64: 141-175. https://doi.org/10.3897/jhr.64.24282

Fagan-Jeffries EP, Cooper SJB, Austin AD (2018) Three new species of Dolichogenidea Viereck (Hymenoptera, Braconidae, Microgastrinae) from Australia with exceptionally long ovipositors. Journal of Hymenoptera Research 64: 177-190. https://doi.org/10.3897/jhr.64.25219

Boeve; J, Dominguez D, Smith D (2018) Sawflies from northern Ecuador and a checklist for the country (Hymenoptera: Argidae, Orussidae, Pergidae, Tenthredinidae, Xiphydriidae). Journal of Hymenoptera Research 64: 1-24. https://doi.org/10.3897/jhr.64.24408

Mitrovic M, Tomanovic Z (2018) New internal primers targeting short fragments of the mitochondrial COI region for archival specimens from the subfamily Aphidiinae (Hymenoptera, Braconidae). Journal of Hymenoptera Research 64: 191-210. https://doi.org/10.3897/jhr.64.25399

New wasps named after Crocodile Dundee and Toblerone amongst 17 new genera and 29 species

Five species are also named after institutions holding some of the largest wasp collections

A total of 17 new genera and 29 new species of parasitoid wasps were identified following a study into the material deposited at major natural history collections around the globe in an attempt to further uncover the megadiverse fauna of the group of microgastrine wasps.

The novel taxa known to inhabit the tropics, including the Afrotropical, Australasian, Neotropical and the Oriental region, are published by Dr Jose Fernandez-Triana and Caroline Boudreault of the Canadian National Collection of insects in Ottawa in a monograph in the open access Journal of Hymenoptera Research.

Curiously, amongst the newly described wasps, there are several newly described genera and species, which received particularly amusing names.

Reported from the Australasian region, the genus Qrocodiledundee is not only a nod to the famous Australian action comedy ‘Crocodile Dundee’, which also happens to be a favourite of the lead author’s, but also refers to Jose’s own nickname. In the past, Jose himself used to track down and catch crocodiles for scientific study, and was even bitten by one, much like the fictional character played by Paul Hogan. Further, the so far only member known in the genus carries the name Qrocodiledundee outbackense, where the species name (outbackense) alludes to the Outback – the vast and remote interior of Australia.

Another favourite of the first author, the chocolate brand ‘Toblerone’ was in its turn sewn into the genus name Tobleronius. According to the scientists, a segment in the midsection of the bodies of those wasps resembles the triangle pieces comprising the chocolate bars, “if one has enough imagination and love for chocolate!”

Five of the newly discovered species are named in tribute to five major natural history institutions, which are greatly appreciated by the authors due to their outstanding insect collections. These are the species Billmasonius cienciCarlmuesebecki smithsonianGilbertnixonius biem, Jenopappius magyarmuzeum and Ypsilonigaster naturalis referring to the Canadian National Collection of insects in Ottawa (CNC), the Smithsonian’s National Museum of Natural History, the Natural History Museum in London (formerly known as the British Museum, abbreviated as ‘BM’), the Hungarian Natural History Museum (Magyar Természet-Tudományi Múzeum) and the Naturalis Biodiversity Center in Leiden, respectively.

The rest of the new species and genera were given more conventional names, inspired by the wasps’ distinctive characters, type localities, or were given the names of prominent scientists, as well as beloved friends and family.

Despite of the scale of the present contribution, it is highly likely that there are many more microgastrine wasps still awaiting discovery.

“Although an updated and more comprehensive phylogeny of Microgastrinae is probably years ahead, we hope the present paper contributes toward that goal by describing a significant number of new taxa and making them available for future studies,” conclude the authors.

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Original source:

Fernandez-Triana J, Boudreault C (2018) Seventeen new genera of microgastrine parasitoid wasps (Hymenoptera, Braconidae) from tropical areas of the world. Journal of Hymenoptera Research 64: 25-140. https://doi.org/10.3897/jhr.64.25453

The ‘Star dust’ wasp is a new extinct species named after David Bowie’s alter ego

During her study on fossil insects of the order Hymenoptera at China’s Capitol Normal University, student Longfeng Li visited the Smithsonian National Museum of Natural History, Washington, carrying two unidentified wasp specimens that were exceptionally well-preserved in Burmese amber. This type of fossilized tree resin is known for the quality of the fossil specimens which can be preserved inside it. Being 100 million years old, they provide an incredible view into the past.

The subsequent analysis of the specimens revealed that both represent species new to science. Furthermore, one of the wasps showed such amazing similarities to a modern group of wasps that it was placed in a currently existing genus, Archaeoteleiawhich has long been considered as an ancient lineage. The species are described in a study published in the open access Journal of Hymenoptera Research.

However, Archaeoteleia has changed since the times when the ancient wasp got stuck on fresh tree resin. The authors note that “a novice might not recognize the characters that unite the fossil with extant species”. For instance, the modern wasp species of the genus show visibly longer antennal segments and a different number of teeth on the mandible when compared to the fossil. In turn, the description of the new extinct species enhances the knowledge about living species by highlighting anatomical structures shared by all species within the genus.

This fossil wasp with living relatives received quite a curious name, Archaeoteleia astropulvis. The species name, astropulvis, translates from Latin to ‘star dust’. The discoverers chose the name to refer to both “the ancient source of the atoms that form our planet and its inhabitants”, as well as to commemorate the late David Bowie’s alter ego – Ziggy Stardust.

Unlike the Star dust wasp, the second new species belongs to a genus (Proteroscelio) known exclusively from Cretaceous fossils. Likewise, it is a tiny insect, measuring less than 2mm in length. It also plays an important role in taxonomy by expanding the anatomical diversity known from this extinct genus.

10388_Proteroscelio nexus

The authors conclude that their discovery, especially the Star dust wasp and its placement in an extant genus, where it is the only fossil species, “exemplifies the importance of understanding the extant fauna of a taxon to interpret fossils”.

“Such union of fossil and extant morphologies is especially illuminating and requires examination of both kinds of specimens,” they add.

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Original source:

Talamas EJ, Johnson NF, Buffington ML, Dong R (2016) Archaeoteleia Masner in the Cretaceous and a new species of Proteroscelio Brues (Hymenoptera, Platygastroidea). In: Talamas EJ, Buffington ML (Eds) Advances in the Systematics of Platygastroidea. Journal of Hymenoptera Research 56: 241-261. https://doi.org/10.3897/jhr.56.10388

Bee species with little known nesting-behavior observed to use plastic instead of leaves

Little is known about the nesting activities of some lineages of megachiline bees. Dr. Sarah Gess, affiliated with both Albany Museum and Rhodes University, South Africa, and Peter Roosenschoon, Conservation Officer at the Dubai Desert Conservation Reserve, United Arab Emirates, made use of their earlier observations gathered during a survey on flower visitation in the spring of 2015, to fill some gaps in the knowledge of of three species from such lineages.

Among their findings, published in the open access Journal of Hymenoptera Research, is a curious instance of a bee attempting to build brood cells using green pieces of plastic. Having examined two nests of the leafcutter bee species Megachile (Eurymella) patellimana, they report that one of the females nested in burrows in compacted sandy ground beneath a plant, and the other – in the banks of an irrigation furrow.

11290_Nest of P. grandiceps after emergence of imagines, visible trapped between their natal nest and a nest of Megachile maxillosa

However, while the former was seen carrying a freshly cut leaf, the latter seemed to have discovered a curious substitute in the form of green plastic. Later on, upon checking the nest, the researchers found that the phenomenon they had observed was no isolated incident – at least six identical pieces of narrow, tough, green plastic were grouped together in an apparent attempt to construct a cell. It turns out that the bee had been deliberately cutting off approximately 10-milimetre-long pieces with its large and strong toothed mandibles, before bringing them back to the nest.

“Although perhaps incidentally collected, the novel use of plastics in the nests of bees could reflect ecologically adaptive traits necessary for survival in an increasingly human-dominated environment,” the authors quote an earlier study.

The two studied mason bee species (Megachile (Maximegachile) maxillosa and Pseudoheriades grandiceps) were seen to construct their nests using a mixture of resin and sand in pre-existing cavities, such as trap-nests, above the ground. The researchers note that resin is a common nest-building material among numerous species of mason bees, also known as resin bees. Previously, it has been suggested that apart from making the nest waterproof, the plant secretions may contain substances that fend off parasites.

The authors’ earlier paper exploring the flower visitation by bees and wasps in the Dubai Desert Conservation Reserve is also published in the open-access Journal of Hymenoptera Research.

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Original source:

Gess SK, Roosenschoon PA (2017) Notes on the nesting of three species of Megachilinae in the Dubai Desert Conservation Reserve, UAE. Journal of Hymenoptera Research 54: 43-56. https://doi.org/10.3897/jhr.54.11290

Trapped in a nuclear weapon bunker wood ants survive for years in Poland

Having built their nest over the vertical ventilation pipe of an old nuclear weapon bunker in Poland, every year a large number of wood ants fall down the pipe to never return back to their colony.

Curiously, although trapped in extremely severe conditions underground, the ants have already upped their numbers to these of big, mature natural colonies, while also carrying on with their basic activities of nest maintenance, constructing and moulding. This unique population is described in the open access Journal of Hymenoptera Research by the team of Polish scientist Wojciech Czechowski, Polish Academy of Science.

The studied colony is still unique, despite the fact that there are previously known similar cases, such as a black garden ant colony that found a home in a chassis of an immobilised car, where the insects had built their nest from mud and dry plant remnants stuck to the underbody. Another wood ant colony is known to have lived in almost complete darkness within a cubic wooden box with no openings apart from a narrow slit at the bottom of one side. Yet, unlike the ants from the bunker, they have all had access to the outside world, having deliberately made their own choice to settle in such extraordinary locations.

Thanks to an yearly campaign set to count the hibernating in the same bunker bats, the ant population was discovered in 2013. Interestingly, when the ants were checked on in 2015, the researchers not only found the population still surviving, but even increasing its numbers.9096_image2

According to the estimates, they counted at least several hundred thousand workers, arguably close to a million. Moreover, when the researchers went back to the bunker in 2016, they found the mound’s damage, caused on their previous visit, repaired, which showed the population still managed to maintain their nest almost as if they were leading a normal life.

The ant ‘colony’ was found to have built an earthen mound in a small 2.3 m high room with a base area of 3 m x 1.2 m. Normally, such wood ants settle exclusively on large forested islands, where they can forage enough food to answer the high energy demand of the colony.

However, the confined space within the bunker has not been the only obstacle the ants have been facing in their underground trap. Beside the lacking food and light, the ‘colony’ had to also deal with the low temperatures between the one-metre thick ferroconcrete walls. All year long it was no more than 10 °C.

Understandably, the severe conditions within the bunker made reproduction effectively impossible. Although the scientists did undertake a special search for larvae, pupae, empty cocoons or queens, they found nothing. Nor did they find signs of male offspring.

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Looking for an answer why the population was still seemingly thriving, the scientists deducted that there was a constant influx of newly fallen ants. The metal plate that once covered the pipe outlet had obviously rusted so much that it has been collapsing under a big wood ant colony’s mound built right over the pipe. In fact, the mortality in the bunker is quite high, but the regular ‘newcomers’ turn out to be overcompensating for the dead ants.

“To conclude, the wood ant ‘colony’ described here – although superficially looking like a functioning colony with workers teeming on the surface of the mound – is rather an example of survival of a large amount of workers trapped within a hostile environment in total darkness, with constantly low temperatures and no ample supply of food,” say the authors.

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Original source:

Czechowski W, Rutkowski T, Stephan W, Vepsäläinen K (2016) Living beyond the limits of survival: wood ants trapped in a gigantic pitfall. Journal of Hymenoptera Research 51: 227-239. doi: 10.3897/jhr.51.9096