Tag: Coleoptera

Rediscovering an interesting group of ant-loving beetles

Case-bearer leaf beetles, scientifically called Cryptocephalinae, live a secretive life.

While the adults hide their heads inside their torso, like a cloaked, mysterious figure, their eggs stay hidden inside a case, carefully constructed by their mothers, using fecal pellets. Having already hatched, the larvae and, later, the pupae keep this initial case and build on forming a protective ‘fortress’ that their enemies can mistake for a plant twig or caterpillar frass.

The studied Cryptocephalines genus, like most of the 40,000 known species of leaf beetles, feed on leaves, fruits, flowers, roots and stems. Indeed, some species of leaf beetles are some of the biggest threats to our crops.

A study published in ZooKeys, led by Dr. Federico Agrain, an Argentinian researcher of CONICET, and his colleagues in the USA and Germany, has unveiled some remarkable new patterns in the secretive life of a specific group within the leaf beetle genus that live within ant nests.

Their research highlights that these myrmecophilic (literally, ‘ant-loving’) leaf beetles live mainly among species of the ant families Formicinae and Myrmecinae.

“Living with ants might offer these beetles multiple advantages, and it might have aided the colonization of xeric environments,” hypothesised Dr. Agrain.

“Ants are notoriously territorial and aggressive, sniffing out and killing enemies that try to enter the ant nests. We suspect that these beetles sneak inside the ant nests by mimicking the scent and behavioral profiles of the ants,” suggests Dr. Caroline Chaboo, a leaf beetle expert at the University of Kansas and co-author of the paper. “How else could the beetles get the ants to pick them up outside the nest and take them into the nest where they can live undetected and with an endless food supply?”

These hypotheses need to be tested in future research. In addition to these novel aspects and hypotheses. “Specialized natural enemies, especially parasitoid Hymenoptera (the insect order where ants belong), exploit cryptocephaline beetles inside the ant nests,” says Dr. Matthew Buffington, a research entomologist at the ARS-Systematic Entomology Laboratory in Washington DC, and co-author of the present study.

Key evolutionary steps, needed to be taken by these leaf beetles, so that they are able to form an association with ants, are also discussed by Dr Federico Agrain and his colleagues. How does a leaf beetle find a host ant, enter the nest, survive within the nest, and, later, exit the ant nest? How strong is the strength of the host association? What are the benefits for the host? What about the diet specialization of adult and larvae? These are the sort of questions the scientists ask themselves.

Clearly, there is a wide range of new hypotheses to be investigated and inter-disciplinary approaches will be needed to unravel the secrets to myrmecophily and the covert, enigmatic lives of case-bearer beetles.

Photo Credit:

Original source:

Agrain FA, Buffington ML, Chaboo CS, Chamorro ML, Schöller M (2015) Leaf beetles are ant-nest beetles: the curious life of the juvenile stages of case-bearers (Coleoptera, Chrysomelidae, Cryptocephalinae). In: Jolivet P, Santiago-Blay J, Schmitt M (Eds) Research on Chrysomelidae 5. ZooKeys 547: 133–164. doi: 10.3897/zookeys.547.6098

Over 300 new beetle records for New Brunswick, Canada, in a special issue of ZooKeys

Beetles diversity in New Brunswick, Canada, has elicited the interest of biologists for over a century and continues to do so. In 1991, 1,365 species were known from New Brunswick. That number had increased to 2,703 by 2013, as a result of a series of publications in three previous special ZooKeys issues and other publications. In spite of that work, there were still gaps in the knowledge of the Coleopteran fauna.

Now, a group of insect specialists have joined forces in the name of their love for beetles, and compiled their findings from the last three years, reporting another 303 species for New Brunswick, including thirty-two species new to science. All of these records are published in a special issue, titled “The Coleoptera of New Brunswick and Canada: Providing baseline biodiversity and natural history data” of the open access journal ZooKeys.

It might have been only three years, but the authors of the present issue have expanded the beetle fauna of New Brunswick by 13%. On a longer timeline since 1991, the increase rises to an impressive 124%.

These figures come as a result of the 303 new records for New Brunswick that included 32 species, which the team have found to be new to science, 4 new North American records, 21 new Canadian records, 270 new provincial records, and 45 adventive species that have somehow arrived in the region from elsewhere. As a result, the beetle fauna of New Brunswick currently comprises 3,062 species.

“This information constitutes a baseline of biological knowledge that is critical to support other branches of science,” point out the authors.

“It is important to remind ourselves that the understanding of biological diversity is not possible without taxonomic research, which is thought by many to be the foundation of biological science,” they explain. “Data on the mega-diversity of life and knowledge on species identity and distribution require discovery, description, cataloguing, and organization in order to be made accessible to a wide audience.”

“This work would not have been possible to complete without the enthusiasm, determination, and professionalism of a small number of dedicated individuals who are acknowledged in the papers in this special issue,” the researchers conclude. “We hope that this special issue will generate a positive response and further interest in the Coleoptera fauna of New Brunswick and Canada, as many new discoveries await.”

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Original source:

Webster RP, Bouchard P, Klimaszewski J, Sweeney JD (2016) History of Coleoptera collecting in New Brunswick, Canada: advancing our knowledge of the Coleoptera fauna in the early 21st century. In: Webster RP, Bouchard P, Klimaszewski J (Eds) The Coleoptera of New Brunswick and Canada: providing baseline biodiversity and natural history data. ZooKeys 573: 1-18. doi: 10.3897/zookeys.573.8123

Two brand new dung beetle species from montane grazing sites and forests in Mexico

While carrying out a biodiversity study, a Mexican-Italian research team discovered three new dung beetle species in montane forests disturbed by livestock grazing. Mexico has been a mecca for naturalists, and its dung beetle species are among the best known in the world. This is why the discovery of new species there is noteworthy. The present study, published in the open-access journal ZooKeys, describes two of them and highlights the need to further explore the biodiversity of disturbed ecosystems.

Mexico is a country that holds a vast number of creatures and ecosystems. There is in fact a fascinating phenomenon: tropical forests that have close affinities with South America co-occurring with temperate and arid areas shared with North America. Thus, Mexico has been particularly attractive to explorers ever since the 19th century.

A group of animals that has woken up a special interest for studies in Mexico is the so-called ‘dung beetles’. As their name suggests, dung beetles are insects that feed mainly on mammal faeces.

For decades, an international research team, led by Dr Gonzalo Halffter, has studied dung beetles across the world, especially in Mexico. As a consequence, the Mexican species are some of the best-known. However, Dr Halffter and his team are not interested exclusively in dung beetles, but also in evolutive phenomena, the effects of land-use change, ecosystems modification by human activities, and conservation biology. Such concerns seem to be of particular importance now that the terrestrial ecosystems in Mexico have been severely destroyed and disturbed by people.

Livestock is one of the major drivers of biodiversity loss worldwide, which makes the present discovery particularly impressive. With at least 58% of the area of Mexico occupied with livestock farming, dung beetles are essential in cleaning up. While studying their diversity at conserved forests and cattle grazing sites across the mountains of Mexico, the researchers found some new species of dung beetles.

The first to discover these new dung beetles was Victor Moctezuma, a student of Dr Gonzalo’s at the Instituto de Ecología of Mexico.

“I was carrying out sampling for my Masters Degree studies, but I had no idea that new dung beetles could be found in a forest that is disturbed by human activities, such as livestock grazing and land-use change,” recalls Moctezuma. “So I was really surprised when I discovered three dung beetle species.” One of these species has already been published.

Apart from the two new dung beetles, formally called Onthophagus clavijeroi and Onthophagus martinpierai, the present paper also provides theories about the current distributions of these insects across the Mexican mountains and their putative evolutive relationships. As a whole, the study highlights the importance of disturbed forest for species discovery and conservation.

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Original source:

Moctezuma V, Rossini M, Zunino M, Halffter G (2016) A contribution to the knowledge of the mountain entomofauna of Mexico with a description of two new species of Onthophagus latreille, 1802 (Coleoptera, Scarabaeidae, Scarabaeinae). ZooKeys 572: 23-50. doi:10.3897/zookeys.572.6763

Smooth hunters: How environmental awareness helped the Bushmen to poison their game

Being responsible for providing their food straight from nature, the San tribes, also called Bushmen, have quickly found ways to evolve their hunting methods. It is assumed that it did not take long between the adoption of bowhunting and the application of poison arrow heads. An American team of researchers, led by Dr. Caroline S. Chaboo, University of Kansas, have studied the various substances and their sources used in different San groupings from Namibia and have their paper published in the open-access journal ZooKeys.

A cross-disciplinary examination involving socio-cultural, historical and ecological as well as entomological knowledge and fieldwork has allowed for a report on the poison sources, their preparation, use and antidotes for the two largest San groupings in Namibia and also summarise the scattered information about other seven groups.

While some of the used poisons are derived from certain plants, others have been found to come from specific beetle species. In the present paper, the scientists describe the process of poison preparation, based on their observation among the San peoples. Interestingly, they used neither adults, nor pupae for its production, but only larvae.

An observant hunter first dug up a cocoon from under the soil of the host plant, which he broke open and took out the larva from within. He rolled the larvae between his fingers, rubbing its skin against a stick he used as a pestle, and then extracted its tissue in one of his special tools – an old giraffe or kudu knuckle bone, where he could mix it with the rest of the ingredients. These included a chewed bark of a particular pea flowering plant species and the beans from others.

Although nowadays many San tribes that have used bowhunting and poison arrows in the past have abandoned them due to restrictions, modern tools and change of lifestyle in general, the familiarisation, adoption and development of poison weapons dating back to Ancient times are excellent examples of the cognitive shifts in human evolution.

“Although these San communities live short distances apart, their arrow poisons are diverse, pointing to an incredibly intimate knowledge of their environment,” explain the researchers. “The discovery of arrow poisons was a significant evolutionary step for humankind, yet we are facing the last opportunity to document arrow-poison use in southern African hunter-gatherer societies.”

“Ethnological data collection such as ours, including the collection of terms in the local vernacular, can open new avenues of research about variations in ecology, fauna and flora,” they conclude.

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Original source:

Chaboo CS, Biesele M, Hitchcock RK, Weeks A (2016) Beetle and plant arrow poisons of the Ju|’hoan and Hai||om San peoples of Namibia (Insecta, Coleoptera, Chrysomelidae; Plantae, Anacardiaceae, Apocynaceae, Burseraceae). ZooKeys 558: 9-54. doi: 10.3897/zookeys.558.5957

Twenty-four new beetle species discovered in Australian rain forests

As many as twenty-four new species from Australian rainforests are added to the weevil genus Trigonopterus. Museum scientists Dr. Alexander Riedel, State Museum of Natural History Karlsruhe, Germany, and Rene Tanzler, Zoological State Collection Munich, Germany, have first discovered them among unidentified specimens in different beetle collections. The study is published in the open-access journal ZooKeys.

Australia is well known for its extensive deserts and savanna habitats. However, a great number of native Australian species are restricted to the wet tropical forests along the east coast of northern Queensland. These forests are also the home of the recent discoveries.

Most of the weevil species now recognised as new have already been collected in the 80s and 90s of the past century. Since then they had been resting in museum collections until German researcher Alexander Riedel had the opportunity to study them.

“Usually a delay of decades or even centuries occurs between the encounter of a new species in the field and its thorough scientific study and formal naming,” he explains. “This is due to the small number of experts who focus on species discovery,” he elaborates. “There are millions of unidentified insect specimens stored in collections around the world but only few people have the training necessary to identify those of special interest.”

However, old museum specimens alone are not enough either. Nowadays, researchers try to include DNA data in their descriptions, and the necessary sequencing techniques work more efficiently with freshly collected material. Therefore, the scientists set off to the field after they have studied the collections of others. Nevertheless, the German team were led to the discovery of one additional new species, which had never been seen before. They called itTrigonopterus garradungensis after the place where it was found.

All of the newly described weevils are restricted to small areas. Some are found only in a single locality. Presumably, this is a consequence of their winglessness, which has prevented them from spreading around. Furthermore, most of them dwell in the leaf litter where they are easily overlooked. Usually, they come to light during specific surveys of the litter fauna.

This is what Geoff Monteith from the Queensland Museum in Brisbane, for instance, has done in the past. As a result, his work is now relevant to conservation because highly localised species are extremely vulnerable to changes of their habitat such as climate change or the arrival of invasive species.

It is likely that Trigonopterus weevils have originated in Australia, the oldest landmass in the region. The island of New Guinea is geologically much younger, but there the genus has quickly enough diversified into hundreds of species. Studies investigating such evolutionary processes depend on names and clear diagnoses of the species. As a result of the present research, for the Australian fauna these are now available.

Besides the publication in the open-access journal ZooKeys, high-resolution photographs of each species are uploaded to the Species ID website, along with the scientific description. All this puts a face to the species name, and therefore is an important prerequisite for future studies on their evolution.

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Original Source:

Riedel A, Tanzler R (2016) Revision of the Australian species of the weevil genus Trigonopterus Fauvel. ZooKeys 556: 97-162. doi: 10.3897/zookeys.556.6126

30th anniversary of Symposia on Chysomelidae celebrated in a new leaf beetle-themed issue

For the last 30 years entomologists all over the world have been gathering together on a regular basis, led by their fascination with one of the three most captivating with their colours and numbers beetle families. The most cardinal of these gatherings is the Symposium on Leaf Beetles, nowadays organised every two years, which traditionally culminates into special issues to hold the quintessence from the findings, talks and debates and keep them safe for the future generations. For a fifth time in a row, the latest volume is published in the open-access journal ZooKeys.

The present volume, assembled with the works of a large multinational research team and put together by editors Drs. Michael Schmitt, Ernst-Moritz-Arndt-Universität, Jorge Santiago-Blay and long-year head of the community of leaf beetle researchers, Prof. Pierre Hippolyte Auguste Jolivet, continues the seemingly ever-going task assumed by the community to further build on the knowledge about the taxonomy, distribution, physiology and biology of the amazing creatures.

In light of the news of Prof. Pierre Jolivet’s resignation from his post as head and senior editor of Research on Chrysomelidae, his colleagues and friends from the chrysomelid community have dedicated the present volume to their “spiritus rector”. “We, editors, many authors, and publishers of Research on Chrysomelidae are grateful for Pierre’s permanent intellectual stimulation, his helpful input, and his friendship,” read the final words of the editorial.

Apart from the activities linked to Research on Chrysomelidae, Prof. Pierre Jolivet has been the inspiring leader of the community of leaf beetle researchers for more than half a century. Furthermore, the Normandy-born entomologist has also published works on ants, ant-plant interactions, parasites of insects and even broader topics, such as evolution.

However, with its 30-year legacy the collaborative global initiative does not seem anywhere close to its slowing down. While a sixth consecutive volume of RoC is currently in production with ZooKeys journal, more and more young chrysomelidologists join the community. Meanwhile, the Symposia themselves having been held every four years, now take place every twenty-four months.

“Eight symposia on Chrysomelidae have been held. Many new things have been found but some problems remain unsolved,” conclude the editors.

“It is certain that some areas need more investigation, as Madagascar for instance, and that there remain many biological problems to be solved or to be discovered,” they point their next steps. “Deforestation reduces the number of species and genera, and many will disappear before being described. Few will persist as fossils in the tropics. Millions of insects have existed in the past and will remain unknown forever.”

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Original source:

Jolivet P (2015) Together with 30 years of Symposia on Chrysomelidae! Memories and personal reflections on what we know more about leaf beetles. In: Jolivet P, Santiago-Blay J, Schmitt M (Eds) Research on Chrysomelidae 5. ZooKeys 547: 35-61. doi: 10.3897/zookeys.547.7181

Research on Chrysomelidae 5 Special Issue is available to read and order from here.

Lava attraction: 74 new beetle species found hiding in plain sight on a Hawaiian volcano

Confined to the limits of Haleakala volcano, Maui Island, Hawaii, the beetle fauna there turns out to be not only extremely diverse, but very abundant as well. When Prof. James Liebherr of the Cornell University Insect Collection thoroughly sampled beetle populations on the volcano, he identified 116 species of round-waisted predatory beetles, including 74 new to science. The taxonomic revision, complete with descriptions of the new species, is now published in the open-access journal ZooKeys.

The present discoveries and observations are certainly surprising due to their scale, even though it has been long known that the Hawaiian Islands support disproportionately high levels of biodiversity. For this group of native round-waisted beetles, called Mecyclothorax in the zoological naming system, there are 239 species across the Hawaiian Islands, all of them descended from a single colonizing species.

The 116 species known from Haleakala make that volcano the center of biodiversity for this group within Hawaii. These beetles’ evolution during the 1.2-million-year lifespan of Haleakala volcano means they have speciated faster than most organisms on Earth, including the Hawaiian Drosophila and the cichlid fishes of eastern Africa.

No less striking is the fact that the 74 newly described beetle species previously evaded discovery within the limits of Haleakala’s 1,440 km2 of surface area. Reasons for this include the restricted distributions of many of the beetle species, and the previous lack of comprehensive field sampling. During his research, Prof. Liebherr examined all quarters of the mountain to eventually find many places of 1′ latitude × 1′ longitude where more than 20Mecyclothorax species lived closely together within a limited area of forest.

Most of these diverse microhabitats were discovered in windward rainforests. Moreover, different forest areas, geographically isolated from each other by volcanic lava flows, steep valleys, or extensive mudflows, supported different sets of species. “Haleakala volcano is a large pie with different sets of beetle species living in the different slices,” comments Prof. Liebherr. “Actually the different pie slices are just like the original Hawaiian land divisions called ahu pua’a, showing that the Hawaiian people had a keen sense for how their island home was organized.”

Additionally, the round-waisted beetle species seem to thrive across a wide range of altitudes, with their populations covering the major part of the mountain’s height. Historical as well as modern records have identified representatives of these insects from 450-metre elevation up to the volcano’s summit at 3000 m. However, given land conversion and the influx of alien invasive plants, habitats below about 1000 m have been seriously disrupted, and these elevations support few native beetles.

Looking to the future, Liebherr points out that “the substantial level of sympatry, associated with occupation of diverse microhabitats by these beetles, provides ample information useful for monitoring biodiversity of the natural areas of Haleakala.”

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Original source:

Liebherr JK (2015) The Mecyclothorax beetles (Coleoptera, Carabidae, Moriomorphini) of Haleakala-, Maui: Keystone of a hyperdiverse Hawaiian radiation. ZooKeys 544: 1-407. doi: 10.3897/zookeys.544.6074