Tag: Araneae

Seven new spider species from Brazil named after 7 famous fictional spider characters

Several literary classics from the fantasy genre are further immortalised and linked together thanks to a Brazilian research team who named seven new spiders after them.

Spider characters from A Song of Ice and Fire, Harry Potter, The Lord of the Rings, The Silmarillion, H. P. Lovecraft’s The Call of Cthulhu and the children’s favourite Charlotte’s Web and Little Miss Spider each gave a name to a new small cave-dwelling six-eyed spider inhabiting northern Brazil.

Discovered in iron caves across the state of Pará, northern Brazil, the new species belong to the same Neotropical genus Ochyrocera. They are described in a new research article published in the open access journal ZooKeys by Dr Antonio Brescovit, Dr Igor Cizauskas and Leandro Mota – all affiliated with Instituto Butantan, Sao Paulo.

Interestingly, while all seven previously unknown species prefer staying in the shadows underground, none of them has the adaptations characteristic for exclusively cave-dwelling organisms, such as loss of pigmentation and reduced or missing eyes. They are classified as edaphic troglophile species, which means that they are capable of completing their life cycle away from sunlight, but are not bound to the deepest recesses. Often crawling near the surface, they can even be spotted outside the caves. To describe the species, the scientists collected about 2,000 adult specimens following a 5-year series of field collection trips.

The list of ‘fantasy’ spiders begins with Ochyrocera varys named after Lord Varys from George R. R. Martin’s book series A Song of Ice and Fire. Lord Varys is also known as the Spider because of his manipulative skills and ability to ‘weave’ and command his networks of eyes-and-ears across two continents.

The name of Ochyrocera atlachnacha refers to the Spider God Atlach-Nacha from the universe created by H. P. Lovecraft. Atlach-Nacha is a giant spider with a human-like face which lives in the caves beneath a mountain and spins a web believed to link the world with the Dreamlands.

Two species are named after spider characters from the classic works by J. R. R. Tolkien. Ochyrocera laracna is a species named after the well-known giant spider Laracna (Shelob in English) who attacks main characters Frodo and Sam on their way to Mordor in The Lord of the Rings’ second volume – The Two Towers.

On the other hand, the Brazilian spider’s sibling – Ochyrocera ungoliant – is linked to Laracna’s mother. Ungoliant appears in Tolkien’s book The Silmarillion, whose events take place prior to those of The Lord of the Rings’ second volume The Two Towers. According to the story, Ungoliant translates to Dark Spider in Elvish.

Another staple in the 20th-century fantasy literature, the Harry Potter series, written by J. K. Rowling, also enjoys the attention of the researchers. The species Ochyrocera aragogue is an explicit reference to the talking Aragog, who lives in the dark recesses of the Forbidden Forest. In the second volume of the series, Harry Potter and the Chamber of Secrets, he confronts Harry Potter and Ron Weasley.

The authors do not fail to pay tribute to much less violent spiders known from popular children books. David Kirk’s Little Miss Spider inspires the name of Ochyrocera misspider. The character is remembered with her words: “We have to be good to bugs; all bugs.”

The Ochyrocera charlotte species refers to Charlotte, the spider from E. B. White’s classic Charlotte’s Web who befriends the main character – Wilbur the pig.

It is highly likely that there are many species and populations of this group of spiders yet to be discovered in the Neotropics, since the lack of previous studies in the region. However, the area and its biodiversity are impacted by mining.

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Original source:

Brescovit AD, Cizauskas I, Mota LP (2018) Seven new species of the spider genus Ochyrocera from caves in Floresta Nacional de Carajás, PA, Brazil (Araneae, Ochyroceratidae). ZooKeys 726: 87-130. https://doi.org/10.3897/zookeys.726.19778

New species of marine spider emerges at low tide to remind scientists of Bob Marley

It was 02:00h on 11 January 2009 when the sea along the coastline of Australia’s “Sunshine State” of Queensland receded to such an extent that it exposed a population of water-adapted spiders. The observant researchers who would later describe these spiders as a species new to science, were quick to associate their emergence with reggae legend Bob Marley and his song “High Tide or Low Tide”.

In their paper, published in the open access journal Evolutionary Systematics, the team of Drs. Barbara Baehr, Robert Raven and Danilo Harms, affiliated with Queensland Museum and the University of Hamburg, describe the new Bob Marley’s intertidal spider and also provide new information on two of its previously known, yet understudied, relatives from Samoa and Western Australia.

Unlike the spiders which people are familiar with, the intertidal species, whose representative is Bob Marley’s namesake, are truly marine. They have adapted to the underwater life by hiding in barnacle shells, corals or kelp holdfast during high tide. To breathe, they build air chambers from silk. Once the sea water recedes, though, they are out and about hunting small invertebrates that roam the surfaces of the nearby rocks, corals and plants.

The new species, listed under the scientific name of Desis bobmarleyi, is described based on male and female specimens spotted and collected from brain coral on that night in January.

Both sexes are characterised by predominantly red-brown colours, while their legs are orange-brown and covered with a dense layer of long, thin and dark grey hair-like structures. The females appear to be larger in size with the studied specimen measuring nearly 9 mm, whereas the male was about 6 mm long.

While the exact distribution range of the newly described species remains unknown, it is currently recorded from the intertidal zones of the Great Barrier Reef on the north-eastern coast of Queensland.

“The song ‘High Tide or Low Tide’ promotes love and friendship through all struggles of life,” explain the authors for their curious choice of a name. “It is his music that aided a field trip to Port Douglas in coastal Queensland, Australia, to collect spiders with a highly unique biology.”

Apart from reporting their research, the scientists use their paper to pay tribute to a German naturalist from the late 19th century – Amalie Dietrich, as well as the famous Jamaican singer and songwriter. Both admirable figures, even if representative of very different fields, are seen by the authors as examples of “the adventurous and resilient at heart” human nature in pursuit of freedom and independence.

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Original source:

Baehr BC, Raven R, Harms D (2017) “High Tide or Low Tide”: Desis bobmarleyi sp. n., a new spider from coral reefs in Australia’s Sunshine State and its relative from Sāmoa (Araneae, Desidae, Desis). Evolutionary Systematics 1: 111-120. https://doi.org/10.3897/evolsyst.1.15735

Bird spiders detectives: The solution to a 200-year-old hairy mystery

Three species and three genera of birdeater spiders are described as new to science in a paper recently published in the open access journal ZooKeys. In their study, the Brazilian spider experts, Drs. Caroline Fukushima and Rogério Bertani, Laboratory of Ecology and Evolution, Instituto Butantan, report the diversity of the oldest tarantula genus (Avicularia), whose name derives from a famous 18th-century illustration depicting a bird caught by a spider.

Even though these harmless tarantulas have long been a favourite exotic pet around the world, their identity has remained problematic ever since the first species was described back in 1758 by the “father of modern taxonomy”, Carl Linnaeus.

“He described the species based on a hodgepodge of spiders,” explain the authors. “Over the next centuries, other species with completely different characteristics were called Avicularia creating a huge mess.” As a result, basic questions, such as the characteristic traits of the genus, the number of its species and their localities, have been left unanswered.

To address the confusion, the team studied both newly collected specimens and also specimens from around the world which had previously been deposited in museum collections. Thus, they concluded that, instead of the 49 species previously assigned to the problematic genus, there are in fact only 12, including three new to science.

One of the new species, Avicularia merianae, is named after Maria Sybilla Merian (1647-1717), a pioneering scientist and a remarkable artist who made the famous illustration of a spider eating a bird. In fact, it was her work that gave birth to the popular name used for a whole group of spiders, also known as birdeaters or bird spiders.

Meanwhile, the name of the new genus Ybyrapora, which occurs in the Brazilian Atlantic rainforest, translates to “those that live in trees” from the indigenous local language Tupi. It refers to the arboreal habitat of these species. The other two tarantula genera live exclusively on the Caribbean Islands.

“People think all biologists are like Indiana Jones, with their daily lives full of adventures in the wild. But most of the time, they are much more like Sherlock Holmes – sitting on a chair, collecting and analysing clues (specimens and scientific papers) and then using logical reasoning to solve Nature’s mysteries,” comments Dr. Caroline Fukushima.

“We, taxonomists, are ‘wildlife detectives’ who play an essential role not only in biology and conservation. Our work can also become the grounds for new technologies, medicines and ideas that could solve a variety of problems,” she adds.

“We are delighted to have finally closed one of the oldest unsolved cases,” the authors conclude.

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Original source:

Fukushima CS, Bertani R (2017) Taxonomic revision and cladistic analysis of Avicularia Lamarck, 1818 (Araneae, Theraphosidae, Aviculariinae) with description of three new aviculariine genera. ZooKeys 659: 1-185. https://doi.org/10.3897/zookeys.659.10717

Family of scaffold web spiders increased with ~20% following discovery of 43 new species

Recent study into spider specimens collected from across China, Indonesia, Philippines, Singapore, Thailand, Vietnam and Madagascar over the past 15 years, revealed the striking number of 43 scaffold web spiders that have stayed hidden from science until now. By describing the new species in a paper published in the open access journal ZooKeys, scientists from Sichuan University and the Chinese Academy of Sciences increase the number of a scaffold web spider family (Nesticidae), known from around the world, with about twenty percents.

The studied family of scaffold web spiders is a relatively small group of arachnids, which can be found at almost any locality, apart from Siberia, Central Asia, Northern and Southern Africa and places at high latitude. Prior to the study of Drs Yucheng Lin, Francesco Ballarin and Shuqiang Li, the species counted 245 in total, 12 of which are extinct and known from fossils only. A curious peculiarity in these spiders is their comb of serrated bristles, located on their rear legs, used to pull silk bands for their webs.

Although large-scale taxonomic surveys of scaffold web spiders have long remained scarce, recently the interest towards spider research in China and Southeast Asia has seen a significant rise. Thus, over the last 15 years, Chinese, American and European arachnologists have carried out several surveys, ending up with precious samples. As a result, Dr Yucheng Lin and his team followed with deeper morphological and molecular studies to discover remarkable diversity.

In their work, the researchers have also established a new genus (Speleoticus) for five previously known, but misplaced species, which spend a lot of their time taking shelter in caves.

The majority of scaffold web spiders occur in temperate areas of the Holarctic realm, where the species tend to be medium-sized, long-legged, and prefer cave-like environments. The species found in the tropical and subtropical areas are, on the other hand, usually smaller, with shorter legs, and can be quite often spotted outside, where they crawl in forest litter, on grass, and under stones.

Original source:

Lin Y, Ballarin F, Li S (2016) A survey of the spider family Nesticidae (Arachnida, Araneae) in Asia and Madagascar, with the description of forty-three new species. ZooKeys 627: 1-168. https://doi.org/10.3897/zookeys.627.8629

Species conservation profile of a critically endangered endemic for the Azores spider

Subject to continuing population decline due to a number of factors, an exclusively cave-dwelling (troglobitic) spider endemic to the Azores is considered as Critically Endangered according to the IUCN Red List criteria.

To provide a fast output, potentially benefiting the arachnid’s survival, scientists from the IUCN – Spider and Scorpion Specialist Group and the Azorean Biodiversity Group (cE3c) at University of Azores, where the main objective is to perform research that addresses societal challenges in ecology, evolution and the environment, also known as the three E’s from the centre’s name abbreviation, teamed up with colleagues from University of Barcelona, Spain, and the Finnish Museum of Natural History.

Together, they make use of a specialised novel publication type feature, called Species Conservation Profile, created by the open access journal Biodiversity Data Journal, to provide scholarly credit and citation for the IUCN Red List species page, as well as pinpoint the population trends and the reasons behind them.

The studied spider species (scientifically called Turinyphia cavernicola) is a pale creature with long legs, large eyes and a total size of merely 2 mm in length. These spiders never leave their underground habitats, which are strictly humid lava tubes and volcanic pits. There they build sheet webs in small holes and crevices on the walls of the caves.

Not only is the species restricted to a single island within the Azorean archipelago (Portugal), but it is only found in three caves. Furthermore, out of the three, only one of them is home to a sustainable large population. These caves are under severe threat due to pasture intensification, road construction and tourist activities.

Although there is not much information about the species distribution through the years, with the spider having been discovered as recently as in 2008, the authors make the assumption that originally there have been significantly greater populations. Not only have they studied thoroughly another fifteen caves located on the island without finding any individuals, but they have identified increasing anthropogenic impact on the habitat.

“The species original distribution was potentially very large compared with the current,” the scientists explain. “Relatively intensive searches in and around the current caves where the species occurs have failed to find additional subpopulations.”

“The trend of decline is based on the assumption that this species can occur in all these caves and that the absence is due to anthropogenic disturbance on caves during the last 50 years,” they note.

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Original source:

Borges P, Crespo L, Cardoso P (2016) Species conservation profile of the cave spiderTurinyphia cavernicola (Araneae, Linyphiidae) from Terceira Island, Azores, Portugal.Biodiversity Data Journal 4: e10274. doi: 10.3897/BDJ.4.e10274

New species of spider discovered ‘next door’ at the borders of cereal fields in Spain

The image that comes to mind when we think of new species being discovered is that of scientists sampling in remote tropical forests, where humans have barely set foot in. However, new species waiting to be discovered can in fact be very close to us, even if we live in a strongly humanized continent like Europe.

Scientists Eduardo Morano, University of Castilla-La Mancha, and Dr Raul Bonal, University of Extremadura, have discovered a new species of spider, formally called Cheiracanthium ilicis, in an area which does not match the image of a pristine habitat at all.

The new species was found in a strongly humanized area in central Spain, specifically, in isolated trees at the borders of cereal fields. These trees, mainly Holm oaks (Quercus ilex), are those remaining of the former oak woodlands that once covered the Iberian Peninsula and which have been cleared for centuries.

The systematic sampling revealed the newly discovered spider had a an exclusive preference for Holm Oaks, as all individuals were collected from the trunks and branches of these trees. Therefore, it was named after this tree’s scientific name “ilicis”.

While adults measure about a centimetre in body length, juveniles are smaller and have greenish colouration that mimics new oak shoots.

The mouthparts are proportionally large, as in the case of other species of the genus, like closely related C. mildei. In the case of the latter, the mouthparts are large enough to penetrate human skin, although the effects of the poison appear mild.

From a conservation perspective, the present study puts forward the need to preserve isolated trees in agricultural landscapes. They are not only a refuge to common forest organisms but to novel species yet to be discovered as well.

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Original source:

Morano E, Bonal R (2016) Cheiracanthium ilicis sp. n. (Araneae, Eutichuridae), a novel spider species associated with Holm Oaks (Quercus ilex). ZooKeys 601: 21-39. doi: 10.3897/zookeys.601.8241

A hair’s breadth away: New tarantula species and genus honors Gabriel García Márquez

With its extraordinary defensive hairs, a Colombian tarantula proved itself as not only a new species, but also a new genus. It is hypothesised that the new spider is the first in its subfamily to use its stinging hairs in direct attack instead of ‘kicking’ them into the enemy.

Described in the open access journal ZooKeys by an international research team, led by Carlos Perafán, University of the Republic, Uruguay, the name of the new spider genus honours an indigenous people from the Caribbean coast region, whose language and culture are, unfortunately, at serious risk of extinction. Meanwhile, its species’ name pays tribute to renowned Colombian author and Nobel laureate for his novel ‘One Hundred Years of Solitude’ Gabriel García Márquez.

The new tarantula, formally called Kankuamo marquezi, was discovered in Sierra Nevada de Santa Marta, Colombia. When examined, the arachnid showed something extraordinary about its defensive hairs and its genitalia. The hairs were noted to form a small oval patch of lance-shaped barbs, hypothesised by the scientists to have evolved to defend their owners by direct contact.

On the other hand, when defending against their aggressors, the rest of the tarantulas in this subfamily need to first face the offender and then vigorously rub their hind legs against their stomachs. Aimed and shot at the enemy, a ball of stinging hairs can cause fatal injuries to small mammals when landed into their mucous membrane (the layer that covers the cavities and shrouds the internal organs in the body). Once thrown, the hairs leave a bald spot on the tarantula’s belly.

“This new finding is a great contribution to the knowledge of the arachnids in Colombia and a sign of how much remains to be discovered,” point out he authors.

“The morphological characteristics present on Kankuamo marquezi open the discussion about the phylogenetics relationship between subfamilies of Theraphosidae tarantulas and the evolutionary pressures that gave rise to the urticating hairs.”

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Original source:

Perafán C, Galvis W, Gutiérrez M, Pérez-Miles F (2016) Kankuamo, a new theraphosid genus from Colombia (Araneae, Mygalomorphae), with a new type of urticating setae and divergent male genitalia. ZooKeys 601: 89-109. doi: 10.3897/zookeys.601.7704

Flightless survivors: Incredible invertebrate diversity in Los Angeles metropolitan area

Urban wildlife is surprisingly understudied. We tend to know more about animals in exotic places than about those that live in our cities.

This is why researchers Emile Fiesler, president of Bioveyda Biological Inventories, Surveys, and Biodiversity Assessments, USA, and Tracy Drake, manager of the Madrona Marsh Preserve, looked into the fauna of the Madrona Marsh Preserve, California, a small nature preserve in one of the world’s largest metropolitan areas.

Consequently, they published the astonishing number of 689 species of invertebrates, which have managed to survive decades of farming and oil exploration, followed by development pressures, in the open access Biodiversity Data Journal. The study was minimally invasive as the live animals have been recorded with macro-photography.

Even though it is the insects that first developed the ability to fly, long before the dinosaurs became birds, the latter have always received the most of our attention. This major evolutionary breakthrough, which has occurred more than once in the past, is also a reason why insects are currently the most diverse animals on earth in terms of number of species.

“Insects and other invertebrates have filled all ecological niches and all corners of our planet,” explain the authors. “No surprise that these small creatures conquered our cities and invaded our homes as well.”

Most of the urban dwellers, however, have been introduced – accidentally or deliberately – by humans.

“The remainder – native ‘wild’ species – are able to survive in the city mainly due to their adaptivity,” they point out. “It is therefore surprising to find a number of flightless species in a small area surrounded by urbanization.”

The Madrona Marsh Preserve is located in Torrance, which is part of the Los Angeles metropolitan area. The greater Los Angeles Metropolitan area is one of the world’s largest, with a human population of more than 17 million.

The Madrona Marsh Preserve, boasting seasonal wetlands, is well known as a birdwatchers’ paradise. Besides birds, its other vertebrates (mammals, reptiles, amphibians, and fishes), as well as its flowering plants, are relatively well known. The invertebrate fauna of the Preserve, on the other hand, aside from butterflies and dragonflies, was virtually unknown.

Interestingly, night surveys revealed the presence of a ‘second shift’ diversity, or creatures seemingly complementary to those active during the day.

Among the long-time survivors are wingless camel crickets as well as velvet ants, which are wasps whose flightless females look like furry ants. Another curiosity that intrigued the researchers is an obscure flightless female bradynobaenid wasp.

The researchers were especially surprised by their encounter with a large Solifugid [image 3] – also known as Camel Spider or Wind Scorpion. Solifugids are little-known arachnids that are neither spiders, nor scorpions, and can grow up to 15 cm (6 in). Their order’s name Solifugae translates from Latin as “those that flee from the sun”.

All in all, the biodiversity study resulted in 689 species without a backbone, belonging to 13 classes, 39 orders, and 222 families, found on this island surrounded by urbanization.

“Not unlike the moas and dodos, these ‘island’ inhabitants stayed grounded through the ages,” acknowledge the researchers.

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Original source:

Fiesler E, Drake T (2016) Macro-invertebrate Biodiversity of a Coastal Prairie with Vernal Pool Habitat. Biodiversity Data Journal 4: e6732. doi: 10.3897/BDJ.4.e6732

About the authors:

Emile Fiesler is president of Bioveyda Biodiversity Inventories, Surveys, and Studies, and Tracy Drake is manager of the Madrona Marsh Preserve.

New tarantula named after Johnny Cash among 14 spider species found in the United States

A new species of tarantula named after the famous singer-songwriter Johnny Cash is one of fourteen new spiders discovered in the southwestern United States. While these charismatic spiders have captured the attention of people around the world, and have been made famous by Hollywood, little was actually known about them. The new descriptions nearly double the number of species known from the region. Biologists at Auburn University and Millsaps College have described these hairy, large-bodied spiders in the open-access journal ZooKeys.

“We often hear about how new species are being discovered from remote corners of the Earth, but what is remarkable is that these spiders are in our own backyard,” says Dr. Chris Hamilton, lead author of the study. “With the Earth in the midst of a sixth mass extinction, it is astonishing how little we know about our planet’s biodiversity, even for charismatic groups such as tarantulas.”

Tarantulas within the genus Aphonopelma are among the most unique species of spider in the United States. One aspect of this distinctiveness that is particularly intriguing is the extreme size differences that can be found between species. Some species are quite impressive, reaching six inches (15 centimeters) or more in leg span, while others can fit on the face of an American quarter-dollar coin (see Image 1).

Within the United States, Aphonopelma are found in twelve states across the southern third of the country, ranging west of the Mississippi River to California. These spiders are conspicuous during the warmer months when adult males abandon their burrows in search of mates, yet very little was known about these spiders prior to the study. Dr. Hamilton notes that more than fifty different species of tarantulas had been previously reported from the United States, but that many of them were poorly defined and actually belonged to the same species.

To gain a better understanding of the diversity and distributions of these spiders, the research team spent more than a decade searching for tarantulas throughout scorching deserts, frigid mountains, and other locations in the American Southwest, sometimes literally in someone’s backyard. They studied nearly 3,000 specimens, undertaking the most comprehensive taxonomic study ever performed on a group of tarantulas.

Because most species of tarantula in the United States are very similar in appearance and cannot be distinguished from each other using anatomical features alone, the research team implemented a modern and “integrative” approach to taxonomy by employing anatomical, behavioural, distributional, and genetic data. Their results indicate there are 29 species in the United States, 14 of which are new to science.

Of the new species, one has been named Aphonopelma johnnycashi after the influential American singer-songwriter Johnny Cash. Dr. Hamilton coined the name because the species is found in California near Folsom Prison (famous for Cash’s song “Folsom Prison Blues”) and because mature males are generally solid black in coloration (paying homage to Cash’s distinctive style of dress where he has been referred to as the “Man in black”) (see Image 2).

While the researchers found that most species are abundant and have relatively large distributions, they also noted that some have highly restricted distributions and may require conservation efforts in the not-so-distant future, as they lose their habitats due to climate change and human encroachment.

“Two of the new species are confined to single mountain ranges in southeastern Arizona, one of the United States’ biodiversity hotspots,” says Brent Hendrixson, a co-author of the study. “These fragile habitats are threatened by increased urbanization, recreation, and climate change. There is also some concern that these spiders will become popular in the pet trade due to their rarity, so we need to consider the impact that collectors may have on populations as well.”

In addition to spider specimens collected by the research team, the study used a tremendous number of specimens gathered from museum collections across the United States, including the Auburn University Museum of Natural History (AUMNH). Project senior author Dr. Jason Bond, director of the AUMNH, notes that studies like these highlight the critical role that museum collections play in understanding our planet’s biodiversity. The AUMNH, located in Auburn, Alabama, possesses the second largest collection of Aphonopelma in the world, behind the American Museum of Natural History in New York.

Tarantulas have gained notoriety for their imposing appearance and perceived threat to humans, but Dr. Hamilton notes that the fear is largely unfounded and that the species in the United States do not readily bite, are not dangerous, and are really just “teddy bears with eight legs”.

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Original source:

Hamilton CA, Hendrixson BE, Bond JE (2016) Taxonomic revision of the tarantula genusAphonopelma Pocock, 1901 (Araneae, Mygalomorphae, Theraphosidae) within the United States.ZooKeys 560: 1-340. doi: 10.3897/zookeys.560.6264

To kill a wolf spider: Further observation of a spider wasp larva growing on its host

Having been attacked, paralysed and implanted with a wasp egg to its belly, a wolf spider carries on with its life fully mobile and active. At least, until it is time for the larva to reach out for its first solid meal at a certain development stage. The present study, conducted by a Brazilian team of scientists, led by PhD student Hebert da Silva Souza, Universidade Estadual de Campinas, Sao Paulo, and published in the open-access Journal of Hymenoptera Research, follows the entire cycle of larval development from the egg laying through the formation of a full-grown wasp.

The herein observed wasp species, called Paracyphononyx scapulatus, belongs to a well-known group of spider parasites, which after laying their eggs on a paralysed spider, let it recover and continue living fully mobile until the larvae are mature. However, little has been known about this curious behaviour of this wasp species in particular, since previous studies have already showed differences between the separate members of the genus.

To observe the whole cycle of the wasp larval development, the researchers caught a recently parasitised wolf spider and placed it in a plastic container.

While the larva grew and fed on the abdominal hemolymph, which is the analog to the blood in backboned creatures, its host did not show any peculiarities in its behaviour and even kept its routine being active at night and resting during the day. This is suggested to be attributed to the need of the larva to keep its host safe from predators, such as ants, which could otherwise eat the dead body.

However, ahead of its fifth and last development stage, the larva was seen to double its size and, in the morning, twenty days after the hatching of the egg, it killed its host and fully consumed it within the next forty-eight hours. Having left its host, the larva began to search for a place within the container to construct a cocoon, which took it sixteen hours. Thirty-two days later, a fully grown female wasp emerged.

In comparison, a relative of the observed spider wasp is known to manipulate its host’s behaviour, making it to enwrap itself and the larva in a cocoon-like silken structure so that it is protected while feeding. Yet, it is not certain whether the observed larva’s growth in captivity is not the reason why it had not induced similar behaviour.

In conclusion, the authors suggest that further investigation of the interaction between the two species could provide more information about the evolution of this kind of parasitism, which is likely to have developed independently among the wasp groups.

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Original source:

Souza HS, Messas YF, Masago F, dos Santos ED, Vasconcellos-Neto J (2015) Paracyphononyx scapulatus (Hymenoptera, Pompilidae), a koinobiont ectoparasitoid of Trochosa sp. (Araneae, Lycosidae). Journal of Hymenoptera Research 46: 165-172. doi: 10.3897/JHR.46.5833