Author: Pensoft Editorial Team

The fossil beetle discovered in the 16-23 million years old sediments of the Irtysh River in southern Siberia belongs to the modern species Helophorus sibiricus, a member of the water scavenger beetles (Hydrophiloidea), which is at present widely distributed in Eurasia and reaches even North America. The species was originally described in 1860 by the Russian entomologist Victor Motschulsky based on specimens collected at Lake Baikal. It is aquatic and inhabits various kinds of standing waters, predominantly the grassy temporary pools. Larvae are unknown so far, but are supposed to be terrestrial and predaceous, preying on various invertebrates, as in most other species of the genus.

The Siberian fossil provides new data for the long-lasting debate among scientists about the average duration of an insect species. It was originally estimated to be ca. 2-3 million years based on the available fossil record, but slowly accumulating data begin to show that such an estimate is an oversimplification of the problem. Recently, evolutionary trees dated using molecular clocks suggested that some insect species are rather young, originating during the Ice Ages, but others may have been able to survive the last 10-20 million years until today. The long-living species had to survive the massive changes of the Earth’s climate during the last millions of years – how they managed to do so is another question for scientists to address.

A large missing piece for the acceptance of long-living insects as a general phenomenon and for understanding the reasons for survival of the particular species is the scarcity of the fossils of such species. The reasons seem to be rather straightforward – the majority of the fossils bear too few details to allow a detailed comparison with living species, whose taxonomy is often based on the shape of male genitalia and other details. That is why the fossil discovered by the Czech-Russian-British team is so important: it bears enough details to allow its detailed comparison with the living species. Although the genitalia are not preserved in the fossil, the scientists were lucky that Helophorus beetles bear species-specific granulation on the pronotum which was readily seen on the fossil and allowed its reliable identification.

A life-style associated with an environment which remains stable over time, such as rotten wood, has been suggested as one of the possible ways in which long-living species may have survived from the past. The discovery of a long-living species of an aquatic beetle may indicate that temporary pools in which Helophorus sibiricus is mainly living today may be another example of such a stable environment – it is really not difficult to imagine that the conditions in a pool created in a modern grassland from the melting snow are very similar to those one would have found in such a pool 20 million years ago.

Original source:
Fikáček M, Prokin A, Angus RB (2011) A long-living species of the hydrophiloid beetles: Helophorus sibiricus from the early Miocene deposits of Kartashevo (Siberia, Russia). ZooKeys 130: 239-254. doi: 10.3897/zookeys.130.1378

After being alerted by Alexandr Rasnitsyn (Palaeontological Institute of the Russian Academy of Sciences, Moscow) to two unusual wasps in amber found in New Jersey, USA, Denis Brothers (University of KwaZulu-Natal, South Africa) has determined that they represent a new family of wasps, but with its closest relatives found in South America and South Africa. The study was published in a special issue of the open-access journal ZooKeys dedicated to the 75th birthday of Professor Rasnitsyn.

The new family has been named Plumalexiidae, and comprises one new species, Plumalexius rasnitsyni Brothers, the names honouring Alexandr Rasnitsyn, who is undoubtedly the world’s foremost authority on the diversity and fossil history of the Hymenoptera, the group of insects which comprises wasps, bees, ants, sawflies and their relatives, in commemoration of his 75th birthday.

The only known specimens are two small males found in Late Cretaceous amber from New Jersey, USA, dating from over 90 million years ago, which was apparently formed in a forested swampy environment. A detailed analysis during which they were compared with specimens of a variety of wasp groups, has shown that they are apparently most closely related to the family Plumariidae, now found only in the arid areas of South America and southern Africa and not known from any fossils. Although they share a few features with the Plumariidae, they also look very different, and so are considered best placed in a different family. The dissimilar habitats involved also indicate that their lifestyles and habits must have been different.

This finding raises many questions about the origins of the larger group of stinging wasps to which the new family belongs (the superfamily Chrysidoidea), the reasons for the apparently disjunct distributions of the grouping (Plumalexiidae in North America and Plumariidae in South America and southern Africa), and the biology of the new family (and even that of the Plumariidae, males and females of which have never been associated directly, and whose behaviour has not been observed in the field). These questions can only be answered satisfactorily once additional specimens, preferably from other localities, have been found.

Original source: Brothers DJ (2011) A new Late Cretaceous family of Hymenoptera, and phylogeny of the Plumariidae and Chrysidoidea (Aculeata). In: Shcherbakov DE, Engel MS, Sharkey MJ (Eds) Advances in the Systematics of Fossil and Modern Insects: Honouring Alexandr Rasnitsyn. ZooKeys 130: 515–542. doi: 10.3897/zookeys.130.1591

Important changes that will affect the publication of new names in algae, fungi, and plants accepted by the XVIII International Botanical Congress are detailed in a paper that is being published simultaneously or will be published soon in a total of sixteen leading academic journals. The paper, co-authored by Sandra Knapp (London), John McNeill (Edinburgh) and Nicholas Turland (St. Louis), presents the draft text of new articles to the Code and some ideas for best practice for authors and publishers.

In addition, the journals PhytoKeys and Mycokeys published the same paper translated into Chinese, Portuguese, Russian and Spanish in order to further disseminate these important changes to the wider community of scientists these changes will affect.

The XVIII International Botanical Congress held in Melbourne, Australia in July 2011 approved sweeping changes to the way scientists name new plants, algae, and fungi (previous press release: Electronic publishing ‘goes live’). The Melbourne Code (now re-named the International Code of Nomenclature for algae, fungi, and plants) will allow online-only publication of names of new taxa – what is widely known as e-publication – from 1 January 2012. The mandatory requirement for a Latin diagnosis or description of new taxa of algae, fungi, and plants was changed to allow either English or Latin from the same date.

"Two important amendments to the Code affecting publication of new names – e-publication and the use of Latin and/or English rather than only Latin – will take effect on 1 January 2012, sooner than what would be the traditional timing of 1 January 2013. To prepare the community and journal publishers for these important steps that will come into effect very soon, we publish today a paper that focuses on what e-publication means for the different stakeholders in the process of naming new algae, fungi, and plants" said the lead author Dr Sandra Knapp of the Natural History Museum in London.

This highly important article was published or will be soon re-published in a total of sixteen leading academic journals: BMC Evolutionary Biology, Botanical Journal of the Linnean Society, Brittonia, Cladistics, MycoKeys, Mycotaxon, New Phytologist, North American Fungi, Novon, Opuscula Philolichenum, PhytoKeys, Phytoneuron, Phytotaxa, Plant Diversity and Resources, Systematic Botany and Taxon.

In addition, the inaugural issue of the open access journal MycoKeys, which is published today, features a commentary paper by Professor David Hawksworth (Department of Plant Biology, Universidad Complutense de Madrid and Department of Botany, Natural History Museum, London) entitled "A new dawn for the naming of fungi: impacts of decisions made in Melbourne in July 2011 on the future publication and regulation of fungal names" in which the far-reaching changes affecting nomenclature of fungi are detailed. A critical change in nomenclatural rules for fungi is the adoption of the "one fungus, one name" principle, among others.

English: Knapp S, McNeill J, Turland NJ (2011) Changes to publication requirements made at the XVIII International Botanical Congress in Melbourne – what does e-publication mean for you. PhytoKeys 6: 5-11. doi: 10.3897/phytokeys.6.1960

Chinese: Knapp S, McNeill J, Turland NJ (2011) Translation into Chinese of: "Changes to publication requirements made at the XVIII International Botanical Congress in Melbourne – what does e-publication mean for you?". Translated by Li-Bing Zhang. PhytoKeys 6: 13-19. doi: 10.3897/phytokeys.6.1984

Portuguese: Knapp S, McNeill J, Turland NJ (2011) Translation into Portuguese of: "Changes to publication requirements made at the XVIII International Botanical Congress in Melbourne – what does e-publication mean for you?". Translated by Jefferson Prado, Regina Y. Hirai, and Cíntia Kameyama. PhytoKeys 6: 21-28. doi: 10.3897/phytokeys.6.1985

Spanish: Knapp S, McNeill J, Turland NJ (2011) Translation into Spanish of: "Changes to publication requirements made at the XVIII International Botanical Congress in Melbourne – what does e-publication mean for you?". Translated by Carmen Ulloa Ulloa, Lourdes Rico Arce, and Renée H. Fortunato. PhytoKeys 6: 39-49. doi: 10.3897/phytokeys.6.1990

Russian: Knapp S, McNeill J, Turland NJ (2011) Translation into Russian of: "Changes to publication requirements made at the XVIII International Botanical Congress in Melbourne – what does e-publication mean for you?" Translated by Irina V. Belyaeva and Maria S. Vorontsova. PhytoKeys 6: 29-37. doi: 10.3897/phytokeys.6.2001

Hawksworth DL (2011) A new dawn for the naming of fungi: impacts of decisions made in Melbourne in July 2011 on the future publication and regulation of fungal names. MycoKeys 1: 7-20. doi: 10.3897/mycokeys.1.2062

A new plant species that buries its seeds – the first in its family – was discovered in the Atlantic forest of Bahia, Brazil, by an international team of amateur and professional scientists.

José Carlos Mendes Santos (a.k.a. Louro) is a handyman in rural northeastern Bahia, Brazil – one of the areas of the world with the highest biodiversity. Two years ago, he found a tiny, inch-high plant with white-and-pink flowers in the backyards of the off-the-grid house of amateur botanist and local plant collector Alex Popovkin. The little plant was brought home to be grown on a window sill for closer observation. In parallel, work on its identification began. Thanks to solar power and a satellite connection, Popovkin had access to the Internet, and as was his habit, he uploaded some photographs of the plant to Flickr and contacted several taxonomic experts around the globe. The family (strychnine family, or Loganiaceae) and genus (Spigelia) of the plant were soon established, with a suggestion from a Brazilian botanist that it might be a new species.

A collaboration was started with Lena Struwe, a specialist of the plant’s family at Rutgers University, who had previously described a species in the gentian family from the Andes named after Harry Potter (apparating moon-gentian, Macrocarpaea apparata), and another after the Inca tribe (the Inca ring-gentian, Symbolanthus incaicus). More collections were made, photographs uploaded and specimens deposited at the State University at Feira de Santana (HUEFS) in Bahia, while Mari Carmen Molina, a visiting scientist in Struwe’s lab from Spain, extracted the plant’s DNA. In collaboration with Katherine Mathews from Western Carolina University, it was confirmed that the genus was indeed Spigelia, to which pinkroot, an old North American herbal remedy against intestinal parasites, also belongs.

Only a few miniscule plants were found in the field the first year. They would die each dry season, only to reappear again at the beginning of the rain season. The plant growing on the window sill soon showed a particular and rare characteristic: after fruits were formed, the fruiting branches would bend down, depositing the capsules with seeds on the ground (and sometimes burying them in the soft cover of moss), thereby ensuring that the seeds would end up as close to the mother plant as possible, facilitating its propagation the following season. This phenomenon, called geocarpy, is a rare adaptation to growing in harsh or ephemeral environments. A famous example of geocarpy is the well-known peanut from the legume family that buries its fruits in the ground. The new species, appropriately named Spigelia genuflexa, is described in an open-access paper published this week by the five collaborators in the taxonomic journal PhytoKeys, from where the article can be downloaded for free.

Mr. Popovkin: This is my first botanical publication in a peer-reviewed journal. Hopefully, there will be more to follow. I had since early adolescence felt attraction to plants, especially tropical plants, when working as a volunteer at the greenhouses of the Botanic Garden of the University of St Petersburg, Russia. It took me 30 years to realize my dream of living in the tropics and studying its plants up close. My daily botanizing walks always bring personal discoveries. My help and local fellow collector Louro has also shown great interest in botany.

“It is very easy to think we have found and described most plant species of the world already, but this discovery shows that there are so much left out there without name and recognition”, says Struwe and adds, “This discovery shows that the most amazing living things can be found when you least expect it, during times and places when you really aren’t looking for something new, and suddenly it is right there in front of you. How many of us haven’t had the most brilliant ideas in the shower? The art of  taxonomy is finding as well as being able to recognize something as new or different, which is hard when the world is home to millions of species and very few species experts.”

This case shows that collaboration between amateurs and professional scientists, using both new molecular and traditional methods and making use of the facilities of the Internet can lead to new discoveries and new efficient ways of documenting the world’s biodiversity.

Photographs of Spigelia genuflexa taken by Alex Popovkin are available under a Creative Commons Attribution license (CC BY 2.0) from Flickr.

Original source: Popovkin AV, Mathews KG, Santos JCM, Molina MC, Struwe L (2011) Spigelia genuflexa (Loganiaceae), a new geocarpic species from the Atlantic forest of northeastern Bahia, Brazil. PhytoKeys 6: 47-65. doi: 10.3897/phytokeys.6.1654

Uma nova espécie de planta que enterra as suas sementes – a primeira descoberta na família – foi encontrada na Mata Atlântica do litoral norte da Bahia, Brasil, por um grupo internacional de botânicos amadores e cientistas.

José Carlos Mendes Santos (de apelido “Louro”) é um caseiro na região rural do nordeste da Bahia, Brasil – uma das áreas do mundo com maior biodiversidade. Há dois anos, ele encontrou uma planta minúscula de apenas 3 cm de altura e com flores esbranquiçadas no quintal da casa do botânico amador e coletor local Alex Popovkin. A plantinha foi trazida para casa para ser cultivada na janela para uma observação cuidadosa. Em paralelo, o trabalho sobre a sua identificação começou. Graças à energia solar e uma conexão via satélite, Popovkin teve acesso à Internet, e como era seu hábito, ele enviou algumas fotos da planta para o Flickr e fez contato com diversos especialistas em taxonomia ao redor do mundo. A família (família da estricnina, ou Loganiaceae) e o gênero (Spigelia) da planta foram logo estabelecidos, com uma sugestão de uma botânica brasileira que poderia tratar-se de uma nova espécie.

Uma colaboração foi iniciada com Lena Struwe, especialista da família da planta na Universidade Rutgers, que já havia descrito uma espécie dos Andes da família das gencianas e nomeada após Harry Potter (Macrocarpaea apparata), e outra em homenagem à tribo Inca (Symbolanthus incaicus). Mais coletas foram feitas, mais fotografias detalhadas postas no Flickr e amostras da planta foram depositadas na coleção do Herbário da Universidade Estadual de Feira de Santana (HUEFS) na Bahia. Enquanto isso, Mari Carmen Molina, uma cientista espanhola visitante no laboratório de Struwe, extraiu o DNA da planta, e em colaboração com Katherine Mathews da Western Carolina University no estado da Carolina do Norte confirmaram que o gênero era de fato Spigelia, ao qual também pertence o espigélia (pinkroot), um remédio natural contra parasitas intestinais conhecido há muito na América do Norte.

Somente algumas plantas minúsculas foram encontradas no campo durante o primeiro ano. Elas morrem a cada estação seca, e reaparecerem novamente apenas no início das chuvas. A planta cultivada na janela logo mostrou uma característica bem particular e rara: depois que os frutos são formados, os ramos da inflorescência com os frutos se dobram para baixo, depositando os frutos com sementes no solo (e às vezes enterrando-os sob a superfície macia de musgo), garantindo assim que as sementes acabem se estabelecendo o mais próximo possível da planta-mãe, facilitando a sua propagação na temporada seguinte. Este fenômeno, chamado geocarpia, é uma adaptação rara observada em plantas que geralmente crescem em ambientes rigorosos ou efêmeros. Um exemplo famoso de geocarpia é o bem conhecido amendoim da família das leguminosas, que enterra seus frutos no chão. A nova espécie, apropriadamente chamada Spigelia genuflexa, é descrita em um artigo de livre acesso que foi publicado esta semana pelos cinco colaboradores na revista taxonômica PhytoKeys, de onde o artigo poderá ser baixado gratuitamente.

Mr. Popovkin: Esta é minha primeira publicação botânica em uma revista profissional. Espero poder contribuir ainda mais em breve. Desde o início da minha adolescência, tenho tido uma grande atração pelas plantas, especialmente as plantas tropicais, quando comecei a trabalhar como voluntário nas estufas do jardim botânico da Universidade de São Petersburgo na Rússia. Levei 30 anos para realizar meu sonho de viver nos trópicos e estudar as plantas de perto. Minhas caminhadas diárias em busca por plantas sempre me proporcionam descobertas pessoais. Louro, o meu ajudante e companheiro local de coletas, tem também despertado o interesse pela botânica.

“É muito fácil pensar que já temos encontrado e descrito a maioria das espécies de plantas do mundo, mas esta descoberta mostra que ainda resta muito a ser reconhecido” diz Struwe, e acrescenta “Esta descoberta mostra que o mais fascinante das coisas vivas pode ser encontrado quando a gente menos espera, em lugares e momentos quando a gente realmente não está procurando por alguma coisa nova, e então de repente ela está exatamente ali em frente da gente. Quantos de nós não temos tido as mais brilhantes ideias quando estamos tomando banho? A arte da taxonomia é encontrar, bem como ser capaz de reconhecer algo como novo ou diferente, o que é difícil porque o mundo abriga milhões de espécies, mas pouquíssimas pessoas são especialistas nos diferentes grupos de plantas".

Este caso mostra que a colaboração entre amadores e profissionais cientistas, usando os novos métodos moleculares e os tradicionais e através das facilidades da Internet pode levar a novas descobertas e maneiras eficientes de documentar a biodiversidade mundial.

Fotos de Alex Popovkin estão disponíveis sob a licensa Creative Commons (Attribution 2.0 Generic (CC BY 2.0)):

http://www.flickr.com/photos/plants_of_russian_in_brazil/sets/72157619216710603/with/4627080568/
 

A team of researchers from the Institute of Microbiology, Chinese Academy of Sciences (Xiao-Liang Wang and Yi-Jian Yao), summarized all the available information on the insect species associated with the Tibetan medicinal fungus Ophiocordyceps sinensis through an extensive literature survey and analyzed their relationships with the fungus. The study was published in the open access journal ZooKeys.

The fungus has traditionally been used as a tonic to strengthen the human body and in the treatment of kidney and lung problems. It has also been shown to possess a variety of medicinal effects by recent studies, e.g. immunomodulating, hypocholesterolemic, hypoglycemic, anti-tumor, anti-oxidation and anti-aging activities. Natural products of O. sinensis are now sold at a price higher than Gold. The fungus contributes billions of RMB (Chinese yuan) to the rural economy on the Tibet Plateau each year and often accounts for 70%～90% of a local family’s annual income. Thousands and thousands of collectors crowd onto the Tibet Plateau every summer, causing a sharp decrease in the natural production of O. sinensis and serious damages to the environment.

“Ophiocordyceps sinensis (also Cordyceps sinensis), known as the Chinese Caterpillar Fungus or ‘Dong Chong Xia Cao’ (winter worm, summer grass) in Chinese, is one of the most widely recognized Traditional Chinese Medicines endemic to the Tibetan Plateau. It has been listed as an endangered species under the second class of state protection since 1999 by the Chinese government and has a striking developmental biology. As a Sac (ascomycete) fungus, it parasitizes larvae of moths of  the family Hepialidae and converts them into sclerotized bodies from which the fungus fruiting body grows. So the natural production of this fungus is closely related to its insect hosts.” said the corresponding author Prof. Yi-Jian Yao.

Since the late 1950s, much effort has been devoted to the study of insect species related to O. sinensis in China. However, the number of insect host species of O. sinensis and the relationship between those insects and the fungus remains unclear.

In the study by Wang and Yao, a total of 4793 related publications, in either English or Chinese, were obtained and analyzed. Ninety-one insect names spanning 13 genera of Chinese Hepialidae moths were gathered from the literature search, together with detailed information of their geographic distribution and altitude. The relationships between the reported insect species and O. sinensis were analyzed based on the overlap of their geographic distribution and altitude range. Fifty-seven of these insects are considered as recognizable potential host species of the fungus, whilst eight are considered as indeterminate hosts and 26 as non-hosts.

The results of this study provide basic information for management of the insect resources and for the conservation and sustainable use of O. sinensis. It will lay a foundation for further studies of the relationship between the fungus and its hosts, especially their co-evolution (an ongoing research project based on DNA sequence analyses in Prof. Yao’s laboratory).

Original source:
Wang X-L, Yao Y-J (2011) Host insect species of Ophiocordyceps sinensis: a review. ZooKeys 127: 43–59. doi: 10.3897/zookeys.127.802

In one of the first taxonomic revisions of Neotropical butterflies that utilizes ‘DNA barcoding’, Andrei Sourakov (University of Florida, Florida Museum of Natural History) and Evgeny Zakharov (University of Guelph, Canadian Centre for DNA Barcoding at the Biodiversity Institute of Ontario) uncovered a spectacular degree of evolutionary divergence within the satyrine butterfly genus Calisto. The study was published in the open-access journal Comparative Cytogenetics.

The Caribbean has a remarkable diversity of habitats and wildlife. More than 200 species of butterflies belonging to some 100 genera live on the islands, with most genera represented by a single species. Many species are endemic to the region, that is they do not occur anywhere else. This distinctive fauna apparently arose as a result of species immigrating from the mainland at some point during the islands’ history, and later evolving mostly into island isolates.

The satyrine butterfly genus Calisto is the most notable of them, because it has the largest number of extant species compared to other butterfly genera found in the region. Until the present revision, Calisto had comprised 54 named taxa, which occupy an extremely diverse array of habitats, suggestive of adaptive radiation on the scale of other classic examples, such as the Galápagos or Darwin’s finches.

The authors of the study applied a new set of molecular characters to clarify the classification and evolution of Calisto butterflies. The ‘DNA barcoding’ technique is based on the analysis of short, standardized gene region within mitochondrial DNA, and provides an efficient method for species identification. As a result, Calisto now contains 34 species and 17 subspecies and new data shed light on the general evolutionary history of the genus.

The discovered spectacular degree of DNA divergence suggests a diversification period of 4-8 million years. Species of Calisto that occur only in Puerto Rico, Cuba, and Jamaica were found likely to have evolved from various Hispaniolan ancestors. The study found no support for previously advocated theories of evolution through geographic separation events due to plate tectonics. The evolutionary time-frame and the phylogenetic position of non-Hispaniolan taxa suggest that ancient dispersal events from Hispaniola to other islands and adaptive radiation within Hispaniola are likely responsible for the diversification within the genus Calisto.

Original source: Sourakov A, Zakharov EV (2011) "Darwin’s butterflies"? DNA barcoding and the radiation of the endemic Caribbean butterfly genus Calisto (Lepidoptera, Nymphalidae, Satyrinae). Comparative Cytogenetics 5(3): 191-210. doi: 10.3897/CompCytogen.v5i3.1730

Why different species have dissimilar sets of chromosomes? Why the differentiated species often conserve apparently identical chromosome complements? Furthermore, why, while chromosome rearrangements can considerably change the course of species evolution, certain variation among individuals and populations of some species persists indefinitely? Such questions motivate researchers to compare chromosomes in closely related species.

To understand the nature of chromosome changes in the voles Microtus savii, researchers from the Rome State University "Sapienza" launched a molecular cytogenetic study. Three of the five Italian forms of pine voles showed remarkable differences in chromosomal distribution of two molecular markers. Analyzing these data and weighing them against previously obtained genetic information, the authors expect to improve the taxonomy of these rodents and to track the pathway of their chromosomal evolution.

The Italian pine voles have long been known as a "species complex", namely the Microtus savii complex. The group includes five "forms": "savii", "brachycercus", "nebrodensis", "niethammericus", and "tolfetanus", distributed throughout the Apennine peninsula. The most widely dispersed is "savii"; "brachycercus" lives in Calabria, "niethammericus" inhabits the Southeast part of the peninsula, while "nebrodensis" is restricted to Sicily.

These ground voles have evolved at different times either with or without chromosomal rearrangements. Chromosomal distribution of specific genes and DNA sequences can help to distinguish between related species with very similar, apparently identical, chromosomes. By localization of such molecular "markers" on chromosomes, or so-called "physical mapping", researchers evidence differences that are normally invisible in microscope. These differences indicate "hidden" processes of chromosome diversification.

Original source: Gornung E, Bezerra AMR, Castiglia R (2011) Comparative chromosome mapping of the rRNA genes and telomeric repeats in three Italian pine voles of the Microtus savii s.l. complex (Rodentia, Cricetidae). Comparative Cytogenetics 5(3): 247-257. doi: 10.3897/CompCytogen.v5i3.1429

Flight attacks of small parasitoid wasps (no larger than 2.0 mm in size) on ant workers have been filmed by José María Gómez Durán from Madrid. The four species of wasps show amazing adaptations and enormous differences in the tactics they use. Two of the four filmed species are new to science and are described by Dr Kees van Achterberg from NCB Naturalis Leiden. The study was published in the open access journal ZooKeys.

Ants are a very dominant group in nature and well-equipped to defend themselves. Only a few small parasitoids manage to break through their defence, thanks to very different and amazing adaptations. The four filmed species belong to four different genera and two different families of wasps (Braconidae and Ichneumonidae). The eggs of the Braconidae develop inside adult ants. The eggs of the Ichneumonidae, however, develop in the larvae of ants. How the newly developed young wasps manage to survive inside the ant nest is still unknown. One of the possible explanations is that dead ants may be deposited outside the entrance of the ant nest, thus giving the young wasps a chance to emerge, avoiding a lethal attack on themselves.

Here are links to four movies, supplementing the article, on Pensoft’s YouTube channel:

Parasitoid wasp (Hybrizon buccatus) ovipositing in ants (Lasius grandis)

Parasitoid wasp (Elasmosoma luxemburgense) ovipositing in ants (Formica rufibarbis)

Parasitoid wasp (Neoneurus vesculus) ovipositing in ants (Formica cunicularia)

Parasitoid wasp (Kollasmosoma sentum) ovipositing in ants (Cataglyphis ibericus)

Original Source: Gómez Durán JM, van Achterberg C (2011) Oviposition behaviour of four ant parasitoids (Hymenoptera, Braconidae, Euphorinae, Neoneurini and Ichneumonidae, Hybrizontinae), with the description of three new European species. ZooKeys 125: 59-106. doi: 10.3897/zookeys.125.1754

New findings of researchers from the University of Modena and Reggio Emilia (Mauro Mandrioli, Valentina Monti and Gian Carlo Manicardi) show that in aphids the two X chromosomes have a different inheritance. The study was published in Comparative Cytogenetics.

Aphids are insects with a sex determination model based on the presence of two X chromosomes (XX) in females and a single X chromosome (XO) in males. Previous studies suggested that X chromosome loss during male determination was random and that both X chromosomes have the same probability to be inherited in males. On the contrary, some authors suggested the presence of strong biases in the transmission of sex chromosomes, so that X chromosomes may have a non-mendelian inheritance in aphids.

On the basis of the results obtained in potato aphid Macrosiphum euphorbiae, we suggest the presence of a non-random elimination of one X chromosome during the male determination process. In particular, the unequal distribution of ribosomal DNA (rDNA) genes between the two X chromosomes could favour the loss of the X chromosome with fewer rDNA genes. This result is due to the fact that all the aphid eggs during the prophase present two X chromosomes linked by rDNA genes. However, in eggs developing as females, the connection is quickly lost, but in male generating eggs the X chromosomes remain attached by rDNA genes and undergo a sort of non-canonical reductional division, so that at the end of this peculiar division, the egg has one X chromosome only and it is determined as a male.

X chromosomes with few rDNA genes seem to be less sticky that X chromosomes with larger rDNA regions, so that their inheritance is not random and X chromosomes with few rDNA genes may be lost and not inherited in males. Mutations in the chromosome structure could therefore affect chromosomal inheritance even if these changes do not affect regions involved in centromere functioning.

Original source:
Monti, V., Manicardi, G.C. Mandrioli, M. (2011) – Cytogenetic and molecular analysis of the holocentric chromosomes of the potato aphid Macrosiphum euphorbiae. Comparative Cytogenetics 5: 163-172.  doi: 10.3897/compcytogen.v5i3.1724