Oldest family of jewel wasps discovered from Cretaceous amber in Lebanon

The new family, Protoitidae, and 10 new species are described in a new paper published in Journal of Hymenoptera Research.

Jewel wasps (Chalcidoidea) are one of the most diverse groups of insects, with more than 120,000 species described and an estimated true diversity of nearly one million. The chalcids are parasitoid wasps, which attack other insects to lay their eggs upon in order to feed and grow within the host. The evolution and origin of this immense group has puzzled scientists for decades. Based on fossils and molecular work, the group is thought to have originated in the late Jurassic around 162 million years ago. Until recently, no confirmed fossils were known from earlier than 100 million years ago. Now, a newly described family, Protoidae, provides the first glimpse into how these wasps appeared at the earliest stages of their evolution.

Protoita noyesi.

Scientists Jonah M. Ulmer, Dr. Petr Janšta, and Prof. Dr. Lars Krogmann, from SMNS – State Museum of Natural History Stuttgart, alongside Dr. Dany Azar from the Lebanese University describe the new family and 10 new species of jewel wasps in a paper in the open-access Journal of Hymenoptera Research.

The discovery of the family came about when one of the coauthors, Prof. Dr. Lars Krogmann, noticed an unusual fossil during a visit to the Natural History Museum in Paris. The specimen embedded in the amber had a long tail-like structure covering its ovipositor. “It was previously described as a completely different type of wasp, however the authors were quick to recognize it was indeed an ancient chalcid. Despite the prevalence of Chalcidoidea in the fossil record, none had ever been recorded from Lebanon or were known to be that old, nearly 130 million years old to be exact,” says Jonah Ulmer.

Cretaxenomerus brevis.

The researchers soon realized they had a new, and very old, family: currently the oldest known within the jewel wasps. “Multiple similar specimens in amber soon became apparent and the family now contains two genera, Protoita and Cretaxenomerus. The family name is derived from being a ‘proto’ form of the Chalcidoidea,” Ulmer explains.

These ancient species present a unique snapshot of what these wasps looked like in their earliest forms, this allows researchers to better understand the order of evolutionary events through time and when certain structures evolved that ultimately led to the massive diversity we see today.

Cretaxenomerus curvus.

The new family’s most striking characteristic is the long, shovel-like process, which extends from the end of the abdomen. While no living species have such a pronounced structure, it is hypothesized to have assisted with egg-laying and ovipositing or perhaps sifting through loose leaf litter for hosts.

The authors note that there are likely other equally old families of Chalcidoidea still lying in wait to be discovered, either in the ground or in old forgotten museum cabinets. “Protoitidae shows that we can keep looking further back in time than we expected and still find new, and old, species” says Ulmer.

Original source:

UImer JM, Janšta P, Azar D, Krogmann L (2023) At the dawn of megadiversity – Protoitidae, a new family of Chalcidoidea (Hymenoptera) from Lower Cretaceous Lebanese amber. Journal of Hymenoptera Research 96: 879-924. https://doi.org/10.3897/jhr.96.105494

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From Down Under to Underground: surprising daddy long-legs spiders discovered in Australia and Réunion

Both spiders were named after mythical underground creatures. The study was published in the journal Subterranean Biology.

Australia’s rich and diverse fauna never fails to surprise us, as a new spider species has been documented from the continent.

The novel species, a blind daddy long-legs, was found in boreholes in the arid Pilbara of Western Australia. It is the first cave-adapted daddy long-legs spider reported from the continent, with other blind species of its genus so far only found in Thailand, Laos, and Vietnam.

Belisana coblynau, male.

“It represents a subfamily that was previously thought to be restricted to the tropical north and east of the continent,” says Bernhard Huber, one of the authors of a recent study published in the journal Subterranean Biology.

“The new species suggests that these spiders were widely distributed in Australia before the continent’s aridification in the last tens of millions of years,” he adds.

Together with it, another extraordinary daddy long-legs species was described as new-to-science from Réunion island. It was collected in the Grotte de La Tortue, a 300,000-year-old lava tube. Its closest known relatives are in eastern Africa, which begs the question how the species reached the island.

The researchers believe its ground-dwelling ancestor arrived to Réunion “relatively recently and by highly accidental means (such as rafts or storms)” but adapted quickly to subterranean life.

“If our generic assignment is correct, then the ancestor of Buitinga ifrit must have reached Réunion from East Africa within the last few million years,” they write in their paper.

Buitinga ifrit, male.

Curiously, both spiders were named after mythical underground dwellers: Belisana coblynau,after “the mythical gnome-like creatures that are said to haunt mines and quarries,” and Buitinga ifrit, after “a demon in Islamic mythology that is often associated with the underworld.”

Original source:

Huber BA, Meng G, Clark HL, Cazanove G (2023) First blind daddy long-legs spiders from Australia and Réunion (Araneae, Pholcidae). Subterranean Biology 46: 1-19. https://doi.org/10.3897/subtbiol.46.105798

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New study in children with language deficits highlights importance of voluntary imagination in language evolution

Contrary to the common assumption, it is voluntary imagination rather than speech that appears to define the pace of combinatorial language evolution

Chimpanzees make use of cobbles to break nuts, but they do not modify them. Homo habilis was one of the earliest hominin species that intentionally modified cobbles to manufacture the crude, Mode One choppers. Homo habilis was only able to break out large flakes from a cobble; its voluntary control of its mental template was quite crude. Homo erectus, on the other hand, was able to break off much smaller flakes and produce the fine, symmetrical, Mode Two hand axes. Therefore, Homo erectus was most likely capable of finer voluntary control of its mental template. Image credit: Andrey Vyshedskiy.

Did the boy bite the cat, or was it the other way around? 

When processing a sentence with several objects, one has to establish ‘who did what to whom’. When a sentence cannot be interpreted by recalling an image from memory, we rely on voluntary imagination to construct a novel mental image in our mind. 

In a previous study, the team of Dr. Andrey Vyshedskiy, a neuroscientist from Boston University, USA, hypothesized that this voluntary imagination ability has fundamental importance for combinatorial language acquisition. To test the hypothesis, the researchers designed a voluntary imagination intervention and administered it to 6,454 children with language deficiencies (age 2 to 12 years). 

In that three-year study, published in 2021, the scientists concluded that children, who were engaged with the voluntary imagination intervention, showed 2.2-fold improvement in combinatorial language comprehension compared to children with similar language deficiencies. These findings suggested that language can be improved by training voluntary imagination and confirmed the importance of the visuospatial component of language. 

In his latest work, now published in the open-science scholarly journal Research Ideas and Outcomes (RIO), Dr. Vyshedskiy builds on these experimental findings to address the question of language evolution and suggest that evolutionary acquisition of language was driven primarily by improvements of voluntary imagination, rather than the speech apparatus.

“Chimpanzees and bonobos can learn hundreds of words. However, apes that know the names of objects, colors, and sizes are not capable of identifying ‘a large red pencil’ among multi-colored, multi-sized pieces of Lego, crayons, and pencils. This suggests that apes cannot mentally integrate color, size and objects together. Thus, voluntary constructive imagination must have been acquired by humans after our ancestors split from chimpanzees 6 million years ago.

Evolutionary development of voluntary imagination can be traced back through the evolution of stone tools, since the process of hand ax manufacturing – for example – requires voluntary imagination of a future tool. 

Apes do not manufacture stone tools, further confirming their imagination limitations. 

Our ancestors started manufacturing crude Mode One choppers about 3.3 million years ago – the first indication of voluntary imagination ability. Then, two million years ago, the emergence of symmetrical Mode Two hand axes with a long cutting edge indicates a major improvement of both tool design and voluntary imagination. Later, approximately 400,000 years ago, the Neanderthals began manufacturing even better Mode Three tools, demonstrating even better voluntary imagination ability. Finally,  about 70,000 years ago, Homo sapiens dramatically extended their tool repertoire as they came up with bows and arrows, needles with eyes, flutes, and composite artworks. This is when most researchers recognize that humanity acquired the modern voluntary imagination ability.”

Dr. Vyshedskiy explains.

Dr. Vyshedskiy proposes that this step-wise development of voluntary imagination – and not the speech apparatus per se – was the key factor underlying the acquisition of modern combinatorial language. 

There are several additional lines of evidence suggesting dissociation of articulate speech and voluntary imagination. 

Firstly, there is significant genetic and archeological evidence that modern speech apparatus was acquired 600,000 years ago, which is quite a long time before acquisition of modern voluntary imagination 70,000 years ago. 

Secondly, mirroring phylogenetic sequences, typical children develop articulate speech by their second year, two years before they acquire the voluntary imagination necessary to comprehend spatial prepositions, recursion, and complex fairy tales. 

Thirdly, speech is not an obligatory component of combinatorial language at all. If early humans had voluntary imagination, they could have invented sign language. All formal sign languages include spatial prepositions and other recursive elements. This has been evidenced in the 1970s, when the largest natural experiment of language origin to date reported on 400 Nicaraguan deaf children from two schools who spontaneously invented a new combinatorial sign language in just a few generations. This means that the capacities of the speech apparatus could not have been a limiting factor in the acquisition of modern combinatorial language at all. 

Fourthly, articulate sounds can be generated by gray parrots and thousands of other songbird species. However, these birds do not acquire combinatorial language. So, evolution of sound articulation is independent from and also a simpler process than improving voluntary imagination. 

In conclusion, on the basis of children studies, neurological observations, archeological findings, combinatorial sign language invention by Nicaraguan deaf children, and variety of sound boxes in birds, Dr. Vyshedskiy argues that the evolution of hominin speech apparatus must have followed (rather than led to) the improvements in voluntary imagination. 

Contrary to the common assumption, it is voluntary imagination rather than speech that appears to define the pace of combinatorial language evolution.

***

Original source:

Vyshedskiy A (2022) Language evolution is not limited to speech acquisition: a large study of language development in children with language deficits highlights the importance of the voluntary imagination component of language. Research Ideas and Outcomes 8: e86401. https://doi.org/10.3897/rio.8.e86401

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Scientists unravel the evolution and relationships for all European butterflies in a first

For the first time, a complete time-calibrated phylogeny for a large group of invertebrates is published for an entire continent. A German-Swedish team of scientists provide a diagrammatic hypothesis of the relationships and evolutionary history for all 496 European species of butterflies currently in existence. Their study provides an important tool for evolutionary and ecological research, meant for the use of insect and ecosystem conservation.

For the first time, a complete time-calibrated phylogeny for a large group of invertebrates is published for an entire continent. 

The figure shows the relationships of the 496 extant European butterfly species in the course of their evolution during the last 100 million years.
Image by Dr Martin Wiemers

In a recent research paper in the open-access, peer-reviewed academic journal ZooKeys, a German-Swedish team of scientists provide a diagrammatic hypothesis of the relationships and evolutionary history for all 496 European species of butterflies currently in existence. Their study provides an important tool for evolutionary and ecological research, meant for the use of insect and ecosystem conservation.

In order to analyse the ancestral relationships and history of evolutionary divergence of all European butterflies currently inhabiting the Old continent, the team led by Martin Wiemers – affiliated with both the Senckenberg German Entomological Institute and the Helmholtz Centre for Environmental Research – UFZ, mainly used molecular data from already published sources available from NCBI GenBank, but also contributed many new sequences, some from very local endemics for which no molecular data had previously been available.

The phylogenetic tree also includes butterfly species that have only recently been discovered using molecular methods. An example is this Blue (Polyommatus celina), which looks similar to the Common Blue. It used to be mistaken for the Common Blue in the Canary Islands and the southwestern part of the Mediterranean Region.
Photo by Dr Martin Wiemers

Butterflies, the spectacular members of the superfamily Papilionoidea, are seen as an important proponent for nature conservation, as they present an excellent indicator group of species, meaning they are capable of inferring the environmental conditions of a particular habitat. All in all, if the local populations of butterflies are thriving, so is their habitat.

Furthermore, butterflies are pollinating insects, which are of particular importance for the survival of humans. There is no doubt they have every right to be recognised as a flagship invertebrate group for conservation.

While many European butterflies are seriously threatened, this one: Madeiran Large White (Pieris wollastoni) is already extinct. The study includes the first sequence of this Madeiran endemic which was recorded in 1986 for the last time. The tree demonstrates that it was closely related to the Canary Island Large White (Pieris cheiranthi), another threatened endemic butterfly, which survives only on Tenerife and La Palma, but is already extinct on La Gomera.
Photo by Dr Martin Wiemers

In recent times, there has been a steady increase in the molecular data available for research, however, those would have been only used for studies restricted either to a selected subset of species, or to small geographic areas. Even though a complete phylogeny of European butterflies was published in 2019, also co-authored by Wiemers, it was not based on a global backbone phylogeny and, therefore, was also not time-calibrated.

In their paper, Wiemers and his team point out that phylogenies are increasingly used across diverse areas of macroecological research, such as studies on large-scale diversity patterns, disentangling historical and contemporary processes, latitudinal diversity gradients or improving species-area relationships. Therefore, this new phylogeny is supposed to help advance further similar ecological research.

The study includes molecular data from 18 localised endemics with no public DNA sequences previously available, such as the Canary Grayling (Hipparchia wyssii), which is only found on the island of Tenerife (Spain).
Photo by Dr Martin Wiemers

Original source: 

Wiemers M, Chazot N, Wheat CW, Schweiger O, Wahlberg N (2020) A complete time-calibrated multi-gene phylogeny of the European butterflies. ZooKeys 938: 97-124. https://doi.org/10.3897/zookeys.938.50878

Recursive language and modern imagination were acquired simultaneously 70,000 years ago

The lion-man sculpture from Germany (dated to 37,000 years ago) must have been first imagined by the artist by mentally synthesizing parts of the man and beast together and then executing the product of this mental creation in ivory. The composite artworks provide a direct evidence that by 37,000 years ago humans have acquired prefrontal synthesis.
Image by JDuckeck
[Public domain, https://commons.wikimedia.org/wiki/File:Lion_man_photo.jpg, Wikimedia Commons]

A genetic mutation that slowed down the development of the prefrontal cortex (PFC) in two or more children may have triggered a cascade of events leading to acquisition of recursive language and modern imagination 70,000 years ago.

This new hypothesis, called Romulus and Remus and coined by Dr. Vyshedskiy, a neuroscientist from Boston University, might be able to solve the long-standing mystery of language evolution. It is published in the open-science journal Research Ideas and Outcomes (RIO).

Numerous archeological and genetic evidence have already convinced most paleoanthropologists that the speech apparatus has reached essentially modern configurations before the human line split from the Neanderthal line 600,000 years ago. Considering that the chimpanzee communication system already has 20 to 100 different vocalizations, it is likely that the modern-like remodeling of the vocal apparatus extended our ancestors’ range of vocalizations by orders of magnitude. In other words, by 600,000 years ago, the number of distinct verbalizations used for communication must have been on par with the number of words in modern languages.

On the other hand, artifacts signifying modern imagination, such as composite figurative arts, elaborate burials, bone needles with an eye, and construction of dwellings arose not earlier than 70,000 years ago. The half million-year-gap between the acquisition of the modern speech apparatus and modern imagination has baffled scientists for decades.

While studying acquisition of imagination in children, Dr. Vyshedskiy and his colleagues discovered a temporal limit for the development of a particular component of imagination. It became apparent that modern children who have not been exposed to full language in early childhood never acquire the type of active constructive imagination essential for juxtaposition of mental objects, known as Prefrontal Synthesis (PFS).

Dr. Vyshedskiy explains:

“To understand the importance of PFS, consider these two sentences: “A dog bit my friend” and “My friend bit a dog.” It is impossible to distinguish the difference in meaning using words or grammar alone, since both words and grammatical structure are identical in these two sentences. Understanding the difference in meaning and appreciating the misfortune of the 1st sentence and the humor of the 2nd sentence depends on the listener’s ability to juxtapose the two mental objects: the friend and the dog. Only after the PFC forms the two different images in front of the mind’s eye, are we able to understand the difference between the two sentences. Similarly, nested explanations, such as “a snake on the boulder to the left of the tall tree that is behind the hill,” force listeners to use PFS to combine objects (a snake, the boulder, the tree, and the hill) into a novel scene. Flexible object combination and nesting (otherwise known as recursion) are characteristic features of all human languages. For this reason, linguists refer to modern languages as recursive languages.”

Unlike vocabulary and grammar acquisition, which can be learned throughout one’s lifetime, there is a strong critical period for the development of PFS and individuals not exposed to conversations with recursive language in early childhood can never acquire PFS as adults. Their language is always lacking understanding of spatial prepositions and recursion that depend on the PFS ability. In a similar manner, pre-modern humans would not have been able to learn recursive language as adults and, therefore, would not be able to teach recursive language to their own children, who, as a result, would not acquire PFS. Thus, the existence of a strong critical period for PFS acquisition creates a cultural evolutionary barrier for acquisition of recursive language.

The second predicted evolutionary barrier was a faster PFC maturation rate and, consequently, a shorter critical period. In modern children the critical period for PFS acquisition closes around the age of five. If the critical period in pre-modern children was over by the age of two, they would have no chance of acquiring PFS. A longer critical period was imperative to provide enough time to train PFS via recursive conversations.

An evolutionary mathematical model, developed by Dr. Vyshedskiy, predicts that humans had to jump both evolutionary barriers within several generations since the “PFC delay” mutation that is found in all modern humans, but not in Neanderthals, is deleterious and is expected to be lost in a population without an associated acquisition of PFS and recursive language. Thus, the model suggests that the “PFC delay” mutation triggered simultaneous synergistic acquisition of PFS and recursive language.

This model calls for:

  • two or more children with extended critical period due to “PFC delay” mutation;
  • these children spending a lot of time talking to each other;
  • inventing the recursive elements of language, such as spatial prepositions;
  • acquiring recursive-conversations-dependent PFS;
  • teaching recursive language to their offsprings.

The hypothesis is named after the celebrated twin founders of Rome, Romulus and Remus. Similar to legendary Romulus and Remus, whose caregiver was a wolf, the real children’s caregivers had an animal-like communication system with many words, but no recursion. Their parents could not have taught them spatial prepositions or recursion; children had to invent recursive elements of language themselves. Such an invention of a new recursive language has been observed in contemporary children, for example among deaf children in Nicaragua.

“The acquisition of PFS and recursive language 70,000 years ago resulted in what was in essence a behaviorally new species: the first behaviorally modern Homo sapiens,” concludes Dr. Vyshedskiy. “This newly acquired power for fast juxtaposition of mental objects in the process of PFS dramatically facilitated mental prototyping and led to fast acceleration of technological progress. Armed with the unprecedented ability to mentally simulate any plan and equally unprecedented ability to communicate it to their companions, humans were poised to quickly become the dominant species.”

Humans acquired an ability to trap large animals and therefore gained a major nutritional advantage. As the population grew exponentially, humans diffused out of Africa and quickly settled in the most habitable areas of the planet, arriving in Australia around 50,000 years ago. These humans were very much like modern humans since they possessed both components of full language: the culturally transmitted recursive language along with the innate predisposition towards PFS, enabled by the “PFC delay” mutation.

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Original source:

Vyshedskiy A (2019) Language evolution to revolution: the leap from rich-vocabulary non-recursive communication system to recursive language 70,000 years ago was associated with acquisition of a novel component of imagination, called Prefrontal Synthesis, enabled by a mutation that slowed down the prefrontal cortex maturation simultaneously in two or more children – the Romulus and Remus hypothesis. Research Ideas and Outcomes 5: e38546. https://doi.org/10.3897/rio.5.e38546

Two fish a day keep the mantid coming back to prey: The 1st fishing praying mantis

Commonly known to predate on insects, praying mantises have occasionally been observed to feed on vertebrates, including small birds, lizards, frogs, newts, mice, snakes and turtles. Mostly, such records have either not been scientifically validated or have occurred under induced and human-manipulated circumstances.

Nevertheless, no scientific data of mantises preying on fish existed until the recent study of Roberto Battiston, Musei del Canal di Brenta, Rajesh Puttaswamaiah, Bat Conservation India Trust, and Nayak Manjunath, published in the open access Journal of Orthoptera Research.

Last year, the team observed an adult male hunting and devouring guppies in a pond located in a private roof garden in Karnataka, India. Curiously enough, the predator came back five days in a row and caught a total of nine fish (a minimum of two a day). To reach its prey, the insect would walk on the leaves of water lilies and water cabbage growing on the surface of the pond.

The artificial pond with the praying mantis sitting on a leaf visible to the right.

Apart from being a curious first-of-its-kind, the observation raises three new discussion points worthy of further study, point out the researchers.

Firstly, the fact that praying mantises hunt on vertebrates outside cages in labs confirms that a single invertebrate species is indeed capable of having an impact on a whole ecosystem. In this case, a mantis preys on guppies which, in their turn, feed on aquatic insects.

The mantis eating a guppy starting from the tail, while the fish is still alive and breathing in the water.

Secondly, the discovery questions previous knowledge about the visual abilities of mantises. While the structure of their eyes clearly indicates that they have evolved to prey in daylight, the studied male specimen proved to be an excellent hunter in the dark. The insect managed to catch all nine fish either at sunset or late at night.

Besides visual, mantises might have evolved impressive learning abilities too. The researchers speculate that the observed repetitive behaviour might have been the result of personal experience, utilised to navigate the specimen. Sophisticated cognitive skills, on the other hand, might have allowed the mantis to develop its hunting strategies.

“Remembering the prey’s abundance in a particular site, in relation to their ease of capture and their nutritional content, could be one important factor of this choice and indirectly influence the individual predator’s fitness,” comment the scientists. “This should be investigated in further studies.”

Ready to hunt.

Original source:

Battiston R, Puttaswamaiah R, Manjunath N (2018) The fishing mantid: predation on fish as a new adaptive strategy for praying mantids (Insecta: Mantodea). Journal of Orthoptera Research27(2): 155-158. https://doi.org/10.3897/jor.27.28067

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

Mosquito populations give a new insight into the role of Caucasus in evolution

We know that the Caucasus is a relatively large mountainous region, situated between Black and the Caspian seas. In its turn, it is divided into three subregions: Ciscaucasia, Greater Caucasus and Transcaucasia, also known as South Caucasus.

A closer look into the chromosome structure of mosquito larvae of a curious group of species (Chironomus “annularius” sensu Strenzke (1959)), collected from the three localities, has allowed Dr Mukhamed Karmokov of the Tembotov Institute of Ecology of Mountain territories at the Russian Academy of Science to figure out how the specificity of the Caucasian region has simultaneously unified its fauna geographically, yet has divided it evolutionarily. His paper is published in the open access journal Comparative Cytogenetics.

Having collected a sufficient amount of mosquito larvae, the researcher managed to study the chromosome structure, rearrangements and possible peculiarities of the separate Caucasian populations, in order to compare them.

Additionally, he analysed their relations to earlier known populations from Europe, Siberia, Kazakhstan and North America.

Amongst the curious peculiarities Karmokov identified in the chromosome structure of the studied larvae were some rearrangements which appear unique to Caucasus. Furthermore, he found that despite the close geographic proximity, the genetic distance between the Caucasian populations is quite significant, even While not enough to determine them as separate species, it could prove them as separate subspecies.

In conclusion, the scientist notes that the obtained data confirm that the Caucasian populations of the studied species have complex genetic structure and provide evidence for microevolution processes in the region.

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Original source:

Karmokov MKh (2018) Karyotype characteristics and chromosomal polymorphism of Chironomus “annularius” sensu Strenzke (1959) (Diptera, Chironomidae) from the Caucasus region. Comparative Cytogenetics 12(3): 267-284. https://doi.org/10.3897/CompCytogen.v12i3.25832

Life in the fast flow: Tadpoles of new species rely on ‘suction cups’ to keep up

The frogs living in the rainforest of Sumatra also represent a new genus

Indonesia, a megadiverse country spanning over 17,000 islands located between Australia and mainland Asia, is home to more than 16% of the world’s known amphibian and reptile species, with almost half of the amphibians found nowhere else in the world. Unsurprisingly, biodiversity scientists have been feverishly discovering and describing fascinating new animals from the exotic island in recent years.

Sumatran forest

Such is the case of an international team from the University of Hamburg, Germany, University of Texas at Arlington, USA, University of Bern, Switzerland and Bandung Institute of Technology, Indonesia, who came across a curious tadpole while collecting amphibian larvae from fast-flowing streams as part of an arduous expedition in the remote forests on the island of Sumatra.

To the amazement of the scientists, it turned out that the tadpoles possess a peculiar cup-like structure on their bellies, in addition to the regular oral disk found in typical tadpoles. As a result, the team described two new species and a genus in the open access journal Zoosystematics and Evolution. A previously known, but misplaced in an unsuitable genus, frog was also added to the group, after it was proved that it takes advantage of the same modification.

This phenomenon where tadpoles display ‘belly suckers’ is known as gastromyzophory and, albeit not unheard of, is a rare adaptation that is only found in certain toads in the Americas and frogs in Asia,” explains lead author Umilaela Arifin.

The abdominal sucker, it is hypothesized, helps these tadpoles to exploit a very special niche – fast-flowing streams – where the water would otherwise be too turbulent and rapid to hang around. Gastromyzophorous species, however, rely on the suction provided by their modified bellies to secure an exclusive access to plentiful food, such as algae, while the less adapted are simply washed away.

When the scientists took a closer look at the peculiar tadpoles and their adult forms, using a powerful combination of molecular and morphological data, they realized that they had not only stumbled upon a rare amphibian trait, but had also discovered two brand new species of frogs in the process.

Sumaterana crassiovis

Moreover, the animals turned out so distinct in their evolutionary makeup, compared to all other frogs, that the scientists had to create a whole new genus to accommodate them. Formally named Sumaterana, the genus is to be commonly referred to as Sumatran Cascade Frogs.

We decided to call the new genus Sumaterana after Sumatra, to reflect the fact that these new species, with their rare evolutionary adaptation are endemic to Sumatra’s rainforests and, in a sense, are emblematic of the exceptional diversity of animals and plants on the island,” says co-author Dr. Utpal Smart. “Tragically, all of them are in peril today, given the current rate of deforestation.

The authors agree that much more taxonomic work is still needed to determine and describe Sumatra’s herpetofaunal diversity, some of which they fear, could be irreversibly lost well before biologists have the chance to discover it.

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Original source:

Arifin U, Smart U, Hertwig ST, Smith EN, Iskandar DT, Haas A (2018) Molecular phylogenetic analysis of a taxonomically unstable ranid from Sumatra, Indonesia, reveals a new genus with gastromyzophorous tadpoles and two new species. Zoosystematics and Evolution 94(1): 163-193. https://doi.org/10.3897/zse.94.22120

Pan-European sampling campaign sheds light on the massive diversity of freshwater plankton

In a major pan-European study, a research team from Germany have successfully extracted environmental DNA (eDNA) from as many as 218 lakes to refute a long-year belief that vital microorganisms do not differ significantly between freshwater bodies and geographic regions the way plants and animals do.

Their new-age approach to biodiversity studies resulted in the largest freshwater dataset along with a study published in the open access journal Metabarcoding and Metagenomics.

Surface freshwaters are of critical importance for terrestrial life and, in particular, human life and welfare. However, these vital ecosystems are severely understudied, as compared to terrestrial or oceanic biomes, and so are the microbial organisms living in them.

Image 2On the other hand, it is these invisible to the naked eye creatures, called protists, that are responsible for keeping our ecosystems running. Their diversity and their high metabolic rates maintain ecosystem stability. In fact, microbes are the major source of the worlds oxygen.

In 2012, the team of Prof. Jens Boenigk, University of Duisburg-Essen, undertook the sampling campaign to study the distribution pattern of microbial organisms on a continental scale and the impact of Europe’s climatic history on their present-day whereabouts.

They sampled freshwater lakes and ponds from sites in Norway, Sweden, Germany, Poland, the Czech Republic, Slovakia, Hungary, Romania, Austria, Italy, France, Spain and Switzerland. Site selection focused on the European orogens, specifically the Alps, the Pyrenees, the Apennine, the High Tatras, the southern Scandinavian mountains and the connecting flatlands.

Thanks to the excellent collaboration both within the team and with a number of scientific institutions across Europe, which gave their support as access points for re-stocking sampling equipment and immediate sample preservation, the campaign delivered groundbreaking results illuminating the hidden diversity of the microbial biosphere.

The scientists reported that plankton diversity was highly partitioned between lakes which bear distinct biological fingerprints. In particular, high mountain ranges imprinted the microbial communities on both regional and continental scale. Ecological factors, such as temperature and nutrient concentrations, are well accepted factors structuring plankton communities.

Beyond the high plankton diversity and the associated highly specific community composition in distinct lakes, the plankton community composition revealed signals of the past, i.e. since the last glaciation some 12,000 years ago.

While this expedition yielded many new scientific findings, the scientists note that these are only the first results of this continental survey.

“We are well aware that we have only just begun our exploration of the hidden diversity of plankton diversity,” they conclude.

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Original source:Probennahme

Boenigk J, Wodniok S, Bock C, Beisser D, Hempel C, Grossmann L, Lange A, Jensen M (2018) Geographic distance and mountain ranges structure freshwater protist communities on a European scale. Metabarcoding and Metagenomics 2: e21519. https://doi.org/10.3897/mbmg.2.21519