Host specialization of parasitoids and their hyperparasitoids on a pair of syntopic aphid species

Parasitoids of herbivorous insects have frequently evolved specialized lineages exploiting hosts occurring on different plants. This study investigated whether host specialization is also observed when closely related parasitoids exploit herbivorous hosts sharing the same host plant. The question was addressed in economically relevant aphid parasitoids of the Lysiphlebus fabarum group. They exploit two aphid species (Aphis fabae cirsiiacanthoides and Brachycaudus cardui), co-occurring in mixed colonies (syntopy) on the spear thistle (Cirsium vulgare). Two morphologically distinguishable parasitoid lineages of the genus Lysiphlebus were observed and each showed virtually perfect host specialization on one of the two aphid species in this system. From A. f. cirsiiacanthoides, only females emerged that morphologically belonged to Lysiphlebus cardui, while males and females belonging to L. fabarum hatched from B. cardui. Microsatellite analyses indicated clear genetic differentiation of L. fabarum and L. cardui. L. cardui comprised only two distinct asexual lineages, one of which predominated throughout the area investigated. Population genetic analysis of sexual L. fabarum showed evidence for relatively strong spatial structuring and limited dispersal ability. Hyperparasitoids emerged from a large proportion of aphid mummies. One species, Pachyneuron aphidis, was significantly associated with B. cardui/L. fabarum mummies, indicating that host specialization may even extend to the trophic level above parasitoid

First Record of the Introduced Ant Myrmica specioides In the Eastern United States

The ant Myrmica specioides Bondroit, 1918 (Hymenoptera: Formicidae) is first reported from the Eastern United States. This species is native to the West Palearctic region and has previously been known as an introduced species in Northwestern North America. It was found 2013 in the Boston metropolitan area. The species was identified by morphometric comparison to type specimens and DNA-barcoding. The distribution and invasive potential of M. specioides are discussed

Reduced entomopathogen abundance in <i>Myrmica</i> ant nests-testing a possible immunological benefit of myrmecophily using <i>Galleria mellonella</i> as a model

Social insects such as ants have evolved collective rather than individual immune defence strategies against diseases and parasites at the level of their societies (colonies), known as social immunity. Ants frequently host other arthropods, so-called myrmecophiles, in their nests. Here, we tested the hypothesis that myrmecophily may partly arise from selection for exploiting the ants’ social immunity. We used larvae of the wax moth Galleria mellonella as ‘model myrmecophiles’ (baits) to test this hypothesis. We found significantly reduced abundance of entomopathogens in ant nests compared with the surrounding environment. Specific entomopathogen groups (Isaria fumosorosea and nematodes) were also found to be significantly less abundant inside than outside ant nests, whereas one entomopathogen (Beauveria brongniartii) was significantly more abundant inside nests. We therefore hypothesize that immunological benefits of entering ant nests may provide us a new explanation of why natural selection acts in favour of such a life-history strategy

Monitoring the influx of new species through citizen science:the first introduced ant in Denmark

Climate change and invasive species threaten biodiversity, yet rigorous monitoring of their impact can be costly. Citizen science is increasingly used as a tool for monitoring exotic species, because citizens are geographically and temporally dispersed, whereas scientists tend to cluster in museums and at universities. Here we report on the establishment of the first exotic ant taxon (Tetramorium immigrans) in Denmark, which was discovered by children participating in The Ant Hunt. The Ant Hunt is a citizen science project for children that we ran in 2017 and 2018, with a pilot study in 2015. T. immigrans was discovered in the Botanical Garden of the Natural History Museum of Denmark in 2015 and confirmed as established in 2018. This finding extends the northern range boundary of T. immigrans by almost 460 km. Using climatic niche modelling, we compared the climatic niche of T. immigrans in Europe with that of T. caespitum based on confirmed observations from 2006 to 2019. T. immigrans and T. caespitum had a 13% niche overlap, with T. immigrans showing stronger occurrence in warmer and drier areas compared to T. caespitum. Mapping the environmental niches onto geographic space identified several, currently uninhabited, areas as climatically suitable for the establishment of T. immigrans. Tetramorium immigrans was sampled almost three times as often in areas with artificial surfaces compared to T. caespitum, suggesting that T. immigrans may not be native to all of Europe and is being accidentally introduced by humans. Overall, citizen scientists collected data on ants closer to cities and harbours than scientists did and had a stronger bias towards areas of human disturbance. This increased sampling effort in areas of likely introduction of exotic species naturally increases the likelihood of discovering species sooner, making citizen science an excellent tool for exotic species monitoring, as long as trained scientists are involved in the identification process

Integrative taxonomy reveals cryptic diversity in North American Lasius ants, and an overlooked introduced species

Biological invasions are a grave threat to ecosystems. The black garden ant (Lasius niger) is a pest species in Europe. Current literature states that L. niger occupies a disjunct native distribution in the Holarctic, however, based on recent work, we re-evaluate this distribution. The native range of L. niger is reconsidered based on phylogenetic relationships (nine mitochondrial and nuclear markers, 5670 bp), DNA-barcoding (98 Holarctic specimens), morphometry (88 Holarctic specimens, 19 different measurements) and subjective assessment of phenotype. The potential spread of this species is estimated using ecological niche modeling. Lasius niger is more closely related to other Palearctic species than to the Nearctic ants known under this name. The latter are described as a distinct species, L. ponderosae sp. nov. However, DNA-barcoding discovered established populations of L. niger in metropolitan areas in Canada (Vancouver and Halifax). We describe a morphometrical method to delineate L. ponderosae sp. nov. and L. niger. MtDNA diversity and divergence is high within L. ponderosae sp. nov., but low within L. niger. More than 1,000,000 km 2 are suitable as a habitat for L. niger in North America. This case emphasizes the critical role of integrative taxonomy to detect cryptic species and identify potential biological invasions in their nascent stages

Integration of Baseline Metabolic Parameters and Mutational Profiles Predicts Long-Term Response to First-Line Therapy in DLBCL Patients: A Post Hoc Analysis of the SAKK38/07 Study.

Accurate estimation of the progression risk after first-line therapy represents an unmet clinical need in diffuse large B-cell lymphoma (DLBCL). Baseline (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) parameters, together with genetic analysis of lymphoma cells, could refine the prediction of treatment failure. We evaluated the combined impact of mutation profiling and baseline PET/CT functional parameters on the outcome of DLBCL patients treated with the R-CHOP14 regimen in the SAKK38/07 clinical trial (NCT00544219). The concomitant presence of mutated SOCS1 with wild-type CREBBP and EP300 defined a group of patients with a favorable prognosis and 2-year progression-free survival (PFS) of 100%. Using an unsupervised recursive partitioning approach, we generated a classification-tree algorithm that predicts treatment outcomes. Patients with elevated metabolic tumor volume (MTV) and high metabolic heterogeneity (MH) (15%) had the highest risk of relapse. Patients with low MTV and favorable mutational profile (9%) had the lowest risk, while the remaining patients constituted the intermediate-risk group (76%). The resulting model stratified patients among three groups with 2-year PFS of 100%, 82%, and 42%, respectively (p < 0.001)

Combined therapy with ibrutinib and bortezomib followed by ibrutinib maintenance in relapsed or refractory mantle cell lymphoma and high-risk features: a phase 1/2 trial of the European MCL network (SAKK 36/13).

BACKGROUND The Bruton's tyrosine kinase inhibitor ibrutinib and the proteasome inhibitor bortezomib have single-agent activity, non-overlapping toxicities, and regulatory approval in mantle cell lymphoma (MCL). In vitro, their combination provides synergistic cytotoxicity. In this investigator-initiated phase 1/2 trial, we established the recommended phase 2 dose of ibrutinib in combination with bortezomib, and assessed its efficacy in patients with relapsed or refractory MCL. METHODS In this phase 1/2 study open in 15 sites in Switzerland, Germany and Italy, patients with relapsed or refractory MCL after ≤2 lines of chemotherapy and both ibrutinib-naïve and bortezomib-naïve received six cycles of ibrutinibb and bortezomib, followed by ibrutinib maintenance. For the phase 1 study, a standard 3 + 3 dose escalation design was used to determine the recommended phase 2 dose of ibrutinib in combination with bortezomib. The primary endpoint in phase 1 was the dose limiting toxicities in cycle 1. The phase 2 study was an open-label, single-arm trial with a Simon's two-stage min-max design, with a primary endpoint of overall response rate (ORR) assessed by CT/MRI. This study was registered with ClinicalTrials.gov, NCT02356458. FINDINGS Between August 2015 and September 2016, nine patients were treated in the phase 1 study, and 49 patients were treated between November 2016 and March 2020 in the phase 2 of the trial. The ORR was 81.8% (90% CI 71.1, 89.8%, CR(u) 21.8%) which increased with continued ibrutinib (median 10.6 months) to 87.3%, (CR(u) 41.8%). 75.6% of patients had at least one high-risk feature (Ki-67 > 30%, blastoid or pleomorphic variant, p53 overexpression, TP53 mutations and/or deletions). In these patients, ibrutinib and bortezomib were also effective with an ORR of 74%, increasing to 82% during maintenance. With a median follow-up of 25.4 months, the median duration of response was 22.7, and the median PFS was 18.6 months. PFS reached 30.8 and 32.9 months for patients with a CR or Cru, respectively. INTERPRETATION The combination of ibrutinib and bortezomib shows durable efficacy in patients with relapsed or refractory MCL, also in the presence of high-risk features. FUNDING SAKK (Hubacher Fund), Swiss State Secretariat for Education, Research and Innovation, Swiss Cancer Research Foundation, and Janssen

Ants of Kamchatka: checklist, DNA-barcoding and key (Hymenoptera, Formicidae)

Kamchatka is a remote volcanic peninsula in the sub-arctic Far East of Russia. Its myrmecofauna has been scientifically addressed several times. However, previous species lists are contradictory in part and a modern study seems to be lacking. Based on literature review, I conclude that 12 species and 4 genera (Camponotus, Formica, Leptothorax and Myrmica) of ants may be native to Kamchatka. Of those, 9 were found in the field, 3 having a Holarctic, 3 a trans-Palearctic and 3 an East Palearctic distribution. Most species diversity was found at mid-elevations, in pine shrubs and mixed forests, while deciduous forests and open habitats at lower altitudes were surprisingly species poor. DNA-barcoding was performed for 57 specimens/9 species. Genetic diversity (COI) was low for 8/9 species, with the exception of Leptothorax acervorum, for which all samples were of a different haplotype and 2 haplogroups were identified. For the encountered Holarctic and trans-Palearctic species, closely related haplotypes (<0.7% raw distance) occur in Europe and/or North America. Some Formica ants were morphologically atypical, with workers partially resembling those of F. fusca, while gynes identified as F. lemani. Morphometric analysis and DNA-barcoding suggested that all these specimens belong to a single species, F. lemani. Standard images for all specimens and an illustrated key to the worker caste are provided