parasitoids

Alternative host-searching strategy reported for the ant parasitoid wasp Ghilaromma orientalis

“In our ten years of frantic observation, we were fortunate enough to observe the parasitic behavior of G. orientalis a single time.”

Guest blog post by Yu Hisasue, Kazuhiko Konishi, and Kenji Takashino

Parasitoid wasps have developed behaviors to adapt to the ecology of various hosts and overcome their means of avoiding parasitism. Host searching behavior is a crucial stage for parasitoids, not only for efficient host search, but also for competing with other parasitoids that exploit the same host as a resource. A variety of such behaviors has been reported, including utilizing chemical or sonic cues. Parasitoid wasps select their strategies based on their own morphology, their host, and the host’s habitat.

Parasitoid wasps that challenge the ant society are known to have highly specialized morphologies and behaviors.

Female of Ghilaromma orientalis hanging from the grass above the ant trail with her head facing the trail.

All members of the subfamily Hybrizontinae are ant parasitoids, and specialize to the ant society, representing the third most diverse group of ant parasitoid wasps after Eucharitidae and Neoneurini. The oviposition behavior has been reported for three species belonging to three different genera in Hybrizontinae: Ogkosoma cremieri, Neohybrizon mutus, and Hybrizon buccatus. In these species, the females hover over an ant trail, and when they come across ant larvae carried by workers, they attack and lay eggs on the ant larvae.

No reports have been made for oviposition behavior in the genus Ghilaromma. G. orientalis was suggested to be a specialist of Lasius nipponensis, but its oviposition behavior was unknown.

Female *Ghilaromma orientalis* using her front legs to contact an ant larva and directing her abdomen towards it, while maintaining a firm grip on the grass with her hind legs.

In our ten years of frantic observation, we were fortunate enough to observe the parasitic behavior of G. orientalis a single time. On 20 October 2015, Kenji Takashino observed the oviposition and took pictures of it on his phone.

He noticed that the female, hung on the grass growing along the ants’ trail on its hind legs with its head down, and when workers with larvae pass by, stretched its abdomen toward the larvae with its hind legs remaining on the grass.

We published these first observations of the oviposition behavior of G. orientalis in a research article in the Journal of Hymenoptera Research.

Female Ghilaromma orientalis maintaining a firm grip on the grass with her hind legs while adjusting her body position to oviposition onto a larva being carried away by an ant.

There are different merits and demerits of the two strategies in Hybrizontinae. The active type has the advantage of covering a wider search area and enabling the movement of the parasitoid to areas where the ants carrying larvae are located. However, this strategy has the drawback that hovering of parasitoid wasps over an ant trail alerts the ants and prevents larva-carrying ants from exiting the nest entrance or covered area. In addition, ants have been observed to open their mandibles to threaten hovering wasps, which then occasionally fail to fly or get captured by worker ants.

Workers of *Lasius nipponensis* with their mandibles open, alerted to the hovering *Ogkosoma cremieri*.

The ambush type has the limitation of a narrow search area. As ant larvae are not always conveniently transported by workers close to the wasp, narrowing the search area directly leads to a decrease in parasitic opportunities. However, the ambush type strategy affords G. orientalis the advantage of laying eggs without being noticed by ants and in a narrow environment where wasps cannot fly in active type.

In addition, we report a new host ant (Lasius cf. fuliginosus) for G. orientalis. Some members of this species group are known to transport their larvae outside the nest. Therefore, it is plausible that G. orientalis may use not only a single ant species, but multiple L. fuliginosus-group species that have a habit of transporting larvae outside the nest.

Although we made only one observation of the wasp, we compared and discussed the other ecological information and parasitic behavior of closely related species using observations, literature, and studies on the parasitic behavior of other well-studied parasitoid wasps.

Research article:

Hisasue Y, Konishi K, Takashino K (2023) An alternative host searching strategy found in the subfamily Hybrizontinae (Hymenoptera, Ichneumonidae). Journal of Hymenoptera Research 96: 629-639. https://doi.org/10.3897/jhr.96.106836

A star in subtropical Japan: a new species of parasitoid wasp constructs unique cocoon masses hanging on 1-meter-long strings

A new species of parasitoid wasp that constructs remarkable star-shaped cocoon masses is reported from the biodiversity hot spot Ryukyu Islands. Japanese researchers observed how the wasps construct “stars” after making their way out of the moth larvae they inhabit during their own larval stage. In their study, published in the open-access journal Journal of Hymenoptera Research, the team discuss the ecological significance of the cocoon mass and the evolution of this peculiar structure.

A unique “star” was discovered from the Ryukyu Islands, a biodiversity hot spot in subtropical Japan: a star-shaped structure that turned out to be the cocoon mass of a new species of parasitoid wasp. Researchers Shunpei Fujie (Osaka Museum of Natural History), So Shimizu, Kaoru Maeto (Kobe University), Koichi Tone (Okinawa Municipal Museum), and Kazunori Matsuo (Kyushu University) described this parasitoid wasp as a new species in the open-access Journal of Hymenoptera Research.

The new parasitoid wasps, *Meteorus stellatus*. Photo by Fujie S

Parasitoid wasps parasitize a variety of organisms, mostly insects. They lay eggs in the host, a larva of hawk moth in this case, where the wasp larvae later hatch. After eating the host from the inside out, the larvae spin threads to form cocoons, in which they pupate, and from which the adult wasps eventually emerge.

The larvae of *Meteorus stellatus* emerging from a host moth. Photo by Tone K

Larvae of the newly discovered parasitoid wasp form star-shaped masses of cocoons lined up in a spherical pattern, suspended by a thread that can reach up to 1 meter in length. The structure, 7 to 14 mm wide and 9 to 23 mm long, can accommodate over 100 cocoons.

The star-shaped cocoon mass and the cable of the new parasitoid wasps. Photo by Shimizu S

Despite its peculiarity, the wasp species constructing these masses had not been previously described: morphological observation and molecular analysis revealed that it was new to science. The authors aptly called it Meteorus stellatus, adding the Latin word for “starry” to its scientific name.

Thanks to the recent publication, we now have the first detailed report about the construction of such a remarkable cocoon mass in parasitoid wasps. We can also see what the process looks like, as the researchers were able to film the wasps escaping from the moth larvae and forming the star-shaped structure.

Why does M. stellatus form cocoons in such a unique structure?

The authors of the study believe this unique structure helps the wasps survive through the most critical time, i.e. the period of constructing cocoons and pupating, when they are exposed to various natural enemies and environmental stresses. The star shape most likely reduces the exposed area of individual cocoons, thus increasing their defense against hyper-parasitoids (wasps attacking cocoons of other parasitoid wasps), while the long thread that suspends the cocoon mass protects the cocoons from potential enemies like ants.

“How parasitoid wasps have evolved to form such unique masses instead of the common individual cocoons should be the next thing on our ‘to-research’ list,” say the authors.

Research article:

Fujie S, Shimizu S, Tone K, Matsuo K, Maeto K (2021) Stars in subtropical Japan: a new gregarious Meteorus species (Hymenoptera, Braconidae, Euphorinae) constructs enigmatic star-shaped pendulous communal cocoons. Journal of Hymenoptera Research 86: 19-45. https://doi.org/10.3897/jhr.86.71225

Dolichomitus meii Wasp Discovered in Amazonia Is Like a Flying Jewel

“The species’ striking colouring protects it from birds that prey on insects. They do not snatch the wasp sitting on the tree trunk as they think it will taste bad or that it is dangerous.”

Parasitoid wasps (Hymenoptera) are one of the most species rich animal taxa on Earth, but their tropical diversity is still poorly known. Now, scientists have discovered the Dolichomitus meii and Polysphincta parasitoid wasp species previously unknown to science in South America. The new species found in the rainforests entice with their colours and exciting habits. Researchers at the University of Turku have already described 53 new animal species this year.

Researchers at the Biodiversity Unit of the University of Turku, Finland, study insect biodiversity particularly in Amazonia and Africa. In their studies, they have discovered hundreds of species previously unknown to science. Many of them are exciting in their size, appearance, or living habits.

“The species we have discovered show what magnificent surprises the Earth’s rainforests can contain. The newly discovered Dolichomitus meii wasp is particularly interesting for its large size and unique colouring. With a quick glance, its body looks black but glitters electric blue in light. Moreover, its wings are golden yellow. Therefore, you could say it’s like a flying jewel,” says Postdoctoral Researcher Diego Pádua from the Instituto Nacional de Pesquisas da Amazônia (INPA) in Brazil, who has also worked at the Biodiversity Unit of the University of Turku.

Dolichomitus parasitoid wasps are parasitic on insect larvae living deep in tree trunks. They lay a single egg on the insect larva and the wasp hatchling eats the host larva as it develops.

“The ovipositor of the Dolichomitus meii wasp is immensely long. It sticks the ovipositor into holes in the wood and tries to find host larvae inside. The species’ striking colouring protects it from birds that prey on insects. They do not snatch the wasp sitting on the tree trunk as they think it will taste bad or that it is dangerous,” says Professor of Biodiversity Research Ilari E. Sääksjärvi from the University of Turku.

Polysphincta Parasitoid Wasps Manipulate the Behaviour of the Host Spider

At the same time as the publication on the Dolichomitus meii species, the researchers published another research article on South American wasp species. The article describes altogether seven new wasp species belonging to the Polysphincta genus.

*Polysphincta bonita* refers to the species’ beautiful appearance. The species is parasitic on spiders. Picture: Diego Padúa and Ilari E. Sääksjärvi

The Polysphincta parasitoid wasps are parasitic on spiders. The female attacks a spider in its web and temporarily paralyses it with a venomous sting. After this, the wasp lays a single egg on the spider, and a larva hatches from the egg. The larva gradually consumes the spider and eventually pupates.

“The wasps that are parasitic on spiders are extremely interesting as many of them can manipulate the behaviour of the host spider. They can change the way a spider spins its web, so that before its death, the spider does not spin a normal web to catch prey. Instead, they spin a safe nest for the parasitoid wasp pupa,” describes Professor Sääksjärvi.

Researchers at University of Turku Have Already Discovered 53 New Species This Year

The new species are often discovered through extensive international collaboration. This was also the case with the newly published studies.

“For example, the discovery of the Dolichomitus meii species was an effort of six researchers. Moreover, these researchers all come from different countries,” says Professor Sääksjärvi.

The work to map out biodiversity previously unknown to science continues at the University of Turku and there are interesting species discoveries ahead.

“I just counted that, in 2021, the researchers of the Biodiversity Unit at the University of Turku have described already 53 new species from different parts of the globe – and we’re only halfway through the year,” Sääksjärvi announces cheerfully.

The discoveries of the research group were published in the Biodiversity Data Journal and ZooKeys.

Research articles:

Di Giovanni F, Pádua DG, Araujo RO, Santos AD, Sääksjärvi IE (2021) A striking new species of Dolichomitus Smith, 1877 (Hymenoptera: Ichneumonidae; Pimplinae) from South America. Biodiversity Data Journal 9: e67438. https://doi.org/10.3897/BDJ.9.e67438

Pádua DG, Sääksjärvi IE, Spasojevic T, Kaunisto KM, Monteiro RF, Oliveira ML (2021) A review of the spider-attacking Polysphincta dizardi species-group (Hymenoptera, Ichneumonidae, Pimplinae), with descriptions of seven new species from South America. ZooKeys 1041: 137-165. https://doi.org/10.3897/zookeys.1041.65407

All microgastrinae wasps from around the world finally together in a 1,089-page monograph

With 3,000 known species and thousands more left to describe, the wasps of the subfamily Microgastrinae are the single most important group of parasitoids attacking the larvae of butterflies and moths, many of which are economically important pests. Consequently, these wasps have a significant impact on both the world’s economy and biodiversity.

Due to their affinities, these wasps are widely used in biological control programs to manage agricultural and forestry pests around the globe. Further, they have also been prominently featured in many basic and applied scientific research (e.g. chemical ecology, biodiversity studies, conservation biology, genomics, behavioural ecology). However, the information about Microgastrinae species is scattered across hundreds of papers, some of which are difficult to find. To make matters worse, there has never been an authoritative checklist of the group at a planetary scale.

All currently available information about the group is now brought together in a large monograph of 1,089 pages, published in the open-access, peer-reviewed journal ZooKeys. The publication presents a total of 2,999 valid extant species belonging to 82 genera. On top of that, the monograph features fossil species and genera, unavailable names and the institutions that store the primary types of all listed species.

Moreover, the researchers have included extensive colour illustrations of all genera and many species (thousands of images in 250 image plates); brief characterisation and diagnosis of all genera; detailed species distributions (within biogeographical regions and per individual country); synopsis of what is known on host-parasitoid associations; summary of available DNA barcodes; estimations of the group diversity at world and regional levels; as well as notes on individual species upon request.

“Compiling this annotated checklist was, more than anything, a labour of love,”
says Dr. Jose Fernandez-Triana of the Canadian National Collection of Insects, lead author of the paper.

Monograph paper openly published in *ZooKeys* at
https://doi.org/10.3897/zookeys.920.39128

“For the past six or seven years, we have spent thousands of hours pouring through hundreds of publications, reading original descriptions in old manuscripts, checking type specimens in many collections worldwide, exchanging information with colleagues from all continents. For the past year or so, I basically stopped all other ongoing research projects I was involved with, to focus solely (almost obsessively!) on finishing this manuscript. The work was often tedious and mind-numbing, and many times I had the temptation to delay the completion of the paper for a later time. However, I was lucky that the other co-authors were just as passionate as myself, and we all pushed each other to finish the task when energy ran low.”

Fifteen species of microgastrinae wasps showing the incredible diversity within the subfamily. Note the variety of colours and shapes.
Image by Dr. Jose Fernandez-Triana

“For the past few years, the Microgastrinae wasps have been one of the most intensively studied groups of insects, at least from a taxonomic perspective,” he adds. “Just to give you an idea: between 2014 and 2019 a total of 720 new species of Microgastrinae were described worldwide. That is an average of one new species every three days, sustained over a six-year period and showing no signs of slowing down.”

He also points out that many scientists from many different countries and biogeographical regions have been involved in the description of the new species. The paper recognises them all and their contributions in the Acknowledgements section.

“You could even say that we are witnessing a renaissance in the study of this group of wasps. However, even then, what has been done is only the tip of the iceberg, as we estimated that only 5 to 10% of all Microgastrinae species have been described. That means that we do not have a name, let alone detailed knowledge, for 90-95% of the remaining species out there. Perhaps, there could be up to 50,000 Microgastrinae wasp species worldwide. It is truly humbling when you consider the magnitude of the work that lies ahead.”

Yet, it is not only a matter of counting huge numbers of species. More importantly, many of those species either have already been put in use as biocontrol agents against a wide range of agricultural and forestry pests, or have the potential to be in the future.

For applied scientists, working with hyperdiverse and poorly known groups such as Microgastrinae is even more perplexing. Navigating the maze of old names, synonyms (species described more than one time under different names), homonyms (same names applied to different species), or unavailable names (names that do not conform to the rules of the International Commission of Zoological Nomenclature) is a daunting task. Often, that results in the same species being referred to in several different ways by different authors and academic works. Consequently, many historical references are full of misleading or even plainly wrong information. Meanwhile, it is very difficult to seek out the useful and correct information.

The present annotated checklist could work as a basic reference for anyone working with or interested in the parasitoid wasps of the subfamily Microgastrinae. In the future, the authors hope to produce revised editions, thus continuing to incorporate new information as it is generated, and to also correct possible mistakes.

“We welcome all kinds of criticisms and suggestions. And we hope that biocontrol practitioners will also help us, the taxonomists, to improve future versions of this work. However, for the time being, let me say that it is a tremendous relief to get this first version out!”
concludes Dr. Fernandez-Triana.

***

Original source:

Fernandez-Triana J, Shaw MR, Boudreault C, Beaudin M, Broad GR (2020) Annotated and illustrated world checklist of Microgastrinae parasitoid wasps (Hymenoptera, Braconidae). ZooKeys 920: 1-1089. https://doi.org/10.3897/zookeys.920.39128.

Revolutionary method could bring us much closer to the description of hyperdiverse faunas

A novel approach relying on a short sequence of mitochondrial DNA in conjunction with a lateral image of the holotype specimen was proposed to greatly accelerate species identification and description, especially when it comes to hyperdiverse taxa, such as parasitic wasps.

At today’s rate, it could take another two millennia for science to document all currently existing species of multicellular life

Two hundred and sixty-one years ago, Linnaeus formalized binomial nomenclature and the modern system of naming organisms. Since the time of his first publication, taxonomists have managed to describe 1.8 million of the estimated 8 to 25 million extant species of multicellular life, somewhere between 7% and 22%. At this rate, the task of treating all species would be accomplished sometime before the year 4,000. In an age of alarming environmental crises, where taking measures for the preservation of our planet’s ecosystems through efficient knowledge is becoming increasingly urgent, humanity cannot afford such dawdling.

“Clearly something needs to change to accelerate this rate, and in this publication we propose a novel approach that employs only a short sequence of mitochondrial DNA in conjunction with a lateral image of the holotype specimen,”
explain the researchers behind a new study, published in the open-access journal Deutsche Entomologische Zeitschrift (DEZ).

Description rate of parasitic wasps species (superfamily
Ichneumonoidea).
Data from Taxapad (Yu et al. 2016).

In standardized practices, it is required that experts conduct plenty of time- and labor-consuming analyses, in order to provide thorough descriptions of both the morphology and genetics of individual species, as well as a long list of characteristic features found to differentiate each from any previously known ones. However, the scientists argue, at this stage, it is impossible to pinpoint distinct morphological characters setting apart all currently known species from the numerous ones not yet encountered. To make matters worse, finding human and financial resources for performing this kind of detailed research is increasingly problematic.

This holds especially true when it comes to hyperdiverse groups, such as ichneumonoid parasitoid wasps: a group of tiny insects believed to comprise up to 1,000,000 species, of which only 44,000 were recognised as valid, according to 2016 data. In their role of parasitoids, these wasps have a key impact on ecosystem stability and diversity. Additionally, many species parasitise the larvae of commercially important pests, so understanding their diversity could help resolve essential issues in agriculture.

Meanwhile, providing a specific species-unique snippet of DNA alongside an image of the specimen used for the description of the species (i.e. holotype) could significantly accelerate the process. By providing a name for a species through a formal description, researchers would allow for their successors to easily build on their discoveries and eventually reach crucial scientific conclusions.

“If this style were to be adopted by a large portion of the taxonomic community, the mission of documenting Earth’s multicellular life could be accomplished in a few generations, provided these organisms are still here,”
say the authors of the study.

To exemplify their revolutionary approach, the scientists use their paper to also describe a total of 18 new species of wasps in two genera (Zelomorpha and Hemichoma) known from Área de Conservación Guanacaste, Costa Rica. Currently, the team works on the treatment of related species, which still comprise only a portion of the hundreds of thousands that remain unnamed.

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Original source:

Meierotto S, Sharkey MJ, Janzen DH, Hallwachs W, Hebert PDN, Chapman EG, Smith MA (2019) A revolutionary protocol to describe understudied hyperdiverse taxa and overcome the taxonomic impediment. Deutsche Entomologische Zeitschrift 66(2): 119-145. https://doi.org/10.3897/dez.66.34683

Two new species of parasitic wasps described from an altitude of over 3,400 m in Tibet

Specimens kept in the collection of the Institute of Beneficial Insects at the Fujian Agriculture and Forestry University (FAFU, China) revealed the existence of two previously unknown species of endoparasitoid wasps. Originally collected in 2013, the insects are known to inhabit prairies and bushes at above 3,400 m, which is quite an unusual altitude for this group of wasps.

The new to science wasps are described and illustrated in a paper published in the open-access, peer-reviewed scholarly journal ZooKeys by the team of Dr Wangzhen Zhang (FAFU and Fuzhou Airport Inspection and Quarantine Bureau) and his colleagues at FAFU: Dr Dongbao Song and Prof Jiahua Chen.

Looking very similar to each other, the species were found to belong to one and the same genus (Microplitis), which, however, is clearly distinct from any other within the subfamily, called Microgastrinae. The latter group comprises tiny, mostly black or brown wasps that develop in the larvae of specific moths or butterflies. Interestingly, once parasitised, the host continues living and does not even terminate its own growth. It is only killed when the wasp eggs hatch and feed on its organs and body fluids before spinning cocoons.

From now on, the newly described wasps will be called by the scientific names Microplitis paizhensis and Microplitis bomiensis, where their species names refer to the localities from where they were originally collected: Paizhen town and Bomi county, respectively.

Due to their parasitism, some microgastrine wasps are considered important pest biocontrol agents. Unfortunately, the hosts of the newly described species remain unknown.

In addition, the scientists also mention a third new to science species spotted amongst the specimens they studied. However, so far they have only found its male, whereas a reliable description of a new microgastrine wasp requires the presence of a female.

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Original source:

Zhang W, Song D, Chen J (2019) Two new species of the genus Microplitis Förster, 1862 (Hymenoptera, Braconidae, Microgastrinae) from China. ZooKeys 859: 49-61. https://doi.org/10.3897/zookeys.859.31720

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

Total of 21 new parasitoid wasps following the first ever revision of their genus

As many as twenty-one species of parasitoid wasps are described as new to science, following the first ever revision of their genus since its establishment back in 1893.

The study simultaneously updates the count of species within the genus (Chromoteleia) to 27 in total, produces a systematic revision of the world’s representatives of this group of wasps, expands their biogeographic knowledge, and clarifies their generic concept.

The monograph is published in the open access journal ZooKeys by a team of US and Canadian scientists, led by Hua-yan Chen, graduate student at the Ohio State University.

The wasps in the genus Chromoteleia are easily distinguished thanks to their large size in combination with their vivid colouration. Compared to other species in the family of platygastrid wasps, which normally measure merely 1 – 2 mm in length, the species in the studied genus range between 3 and 9 mm. Their uncommonly large, robust and elongated bodies is why the scientists assume that these wasps likely parasitise the eggs of orthopterans, such as grasshoppers, crickets and katydids.

A focal point in the study is the intriguing distribution of the wasps. While the genus is widespread throughout continental Mesoamerica, Central America and South America, and its distribution ranges from the Mexican state of Jalisco in the north all the way to Itapúa Department in Paraguay and Paraná in southern Brazil, the species C. congoana is a lone representative of the genus in Africa.

*The ‘lone’ African representative of the genus, Chromoteleia congoana.*

While dispersal from South America to Africa has been observed in the past in another genus of parasitoid wasps (Kapala), the scientists are not willing to reject the possibility of Chromoteleia wasps having been widely distributed across the Old World during a previous geological epoch. Such phenomenon, also known as a relict population, would not mean that the wasp group has subsequently ‘conquered’ the Neotropics and current species inhabiting the New World are rather remainders of once widespread insects.

To conclude their findings, the scientists examined specimens hosted in collections at twenty natural history institutions from around the globe, including the American Entomological Institute; American Museum of Natural History; Bernice P. Bishop Museum; California Academy of Sciences; Canadian National Collection of Insects; California State Collection of Arthropods; Florida State Collection of Arthropods; Instituto Alexander von Humboldt; Illinois Natural History Survey; Kansas University’s Natural History Museum; Museo del Instituto de Museo del Instituto de Zoologia Agricola; Museum National d’Histoire Naturelle; Museu Paraense Emílio Goeldi; Lund Museum of Zoology at Lund University; Triplehorn Insect Collection at the Ohio State University; South African Museum; Texas A&M University’s Insect Collection; Bohart Museum of Entomology; University of Colorado; and Smithsonian National Museum of Natural History.

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Original source:

Chen H-y, Talamas EJ, Valerio AA, Masner L, Johnson NF (2018) Revision of the World species of the genus Chromoteleia Ashmead (Hymenoptera, Platygastridae, Scelioninae). ZooKeys 778: 1-95. https://doi.org/10.3897/zookeys.778.25775

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.

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.

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

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

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 parasitoid wasp likely uses unique saw-like spines to break out of its host body

About the size of a sesame seed, a new species of wasp from Costa Rica, named Dendrocerus scutellaris, has elaborate branched antennae that could be used for finding mates. Or hosts.

The new insect is described by PhD candidate Carolyn Trietsch, Dr. István Mikó and Dr. Andrew Deans of the Frost Entomological Museum at Penn State, USA, together with Dr. David Notton of the Natural History Museum in London, UK. Their study is published in the open access Biodiversity Data Journal.

The wasp is a parasitoid, meaning that its larvae feed on a live host insect. There are two types of parasitoids: ectoparasitoids, which lay their eggs on or near the host, so that the hatchling larvae can attach to and feed on the insect from the outside; and endoparasitoids, which lay their eggs directly inside the host, so that the larvae can eat them from the inside out.

Unfortunately, to puzzle out the new wasp’s lifestyle, the researchers could only rely on specimens collected back in 1985, which had spent the past few decades stored in the collections of the Natural History Museum of London before being loaned to the Frost Museum at Penn State for research.

What can you learn about a wasp’s lifestyle from specimens that are over 30 years old? Even though the new species has never been observed in the wild, researchers managed to learn a lot by looking at the wasps’ morphology, concluding that the species is likely an endoparasitoid.

The larva of an endoparasitoid wasp needs a safe place to develop and mature, so when it is done feeding on its host, it may stay inside the host’s body where it can develop undisturbed. Once it is fully grown, the adult wasp either chews or pushes its way out, killing the host if it isn’t already dead.

Unlike its close relatives, the new species does not have pointed mandibles for chewing. Instead, it has a series of spines along its back. While the wasp is emerging, it may rub these spines against the host and use them like a saw to cut open the body. Once emerged, it flies off to mate and continue the cycle.

“While their lives may sound gruesome, parasitoid wasps are harmless to humans and can even be helpful,” explain the scientists. “Depending on the host they parasitize, parasitoids can benefit agriculture by controlling pest insects like aphids that damage crops.”

It is currently unknown what the new species feeds upon, but naming the species and bringing it to attention is the first step in learning more about it.

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Original source:

Trietsch C, Mikó I, Notton D, Deans A (2018) Unique extrication structure in a new megaspilid, Dendrocerus scutellaris Trietsch & Mikó (Hymenoptera: Megaspilidae). Biodiversity Data Journal 6: e22676. https://doi.org/10.3897/BDJ.6.e22676