Direct sequencing of insect symbionts via nanopore adaptive sampling.

Insect symbionts can alter their host phenotype and their effects can range from beneficial to pathogenic. Moreover, many insects exhibit co-infections, making their study more challenging. Less than 1% of insect species have high-quality referenced genomes available and fewer still also have their symbionts sequenced. Two methods are commonly used to sequence symbionts: whole-genome sequencing to concomitantly capture the host and bacterial genomes, or isolation of the symbiont's genome before sequencing. These methods are limited when dealing with rare or poorly characterized symbionts. Long-read technology is an important tool to generate high-quality genomes as they can overcome high levels of heterozygosity, repeat content, and transposable elements that confound short-read methods. Oxford Nanopore (ONT) adaptive sampling allows a sequencing instrument to select or reject sequences in real time. We describe a method based on ONT adaptive sampling (subtractive) approach that readily permitted the sequencing of the complete genomes of mitochondria, Buchnera and its plasmids (pLeu, pTrp), and Wolbachia genomes in two aphid species, Aphis glycines and Pentalonia nigronervosa. Adaptive sampling is able to retrieve organelles such as mitochondria and symbionts that have high representation in their hosts such as Buchnera and Wolbachia, but is less successful at retrieving symbionts in low concentrations.

Patterns of asexual reproduction of the soybean aphid, Aphis glycines (Matsumura), with and without the secondary symbionts Wolbachia and Arsenophonus, on susceptible and resistant soybean genotypes.

Plant breeding is used to develop crops with host resistance to aphids, however, virulent biotypes often develop that overcome host resistance genes. We tested whether the symbionts, Arsenophonus (A) and Wolbachia (W), affect virulence and fecundity in soybean aphid biotypes Bt1 and Bt3 cultured on whole plants and detached leaves of three resistant, Rag1, Rag2 and Rag1 + 2, and one susceptible, W82, soybean genotypes. Whole plants and individual aphid experiments of A. glycines with and without Arsenophonus and Wolbachia did not show differences in overall fecundity. Differences were observed in peak fecundity, first day of deposition, and day of maximum nymph deposition of individual aphids on detached leaves. Bt3 had higher fecundity than Bt1 on detached leaves of all plant genotypes regardless of bacterial profile. Symbionts did not affect peak fecundity of Bt1 but increased it in Bt3 (A+W+) and all Bt3 strains began to deposit nymphs earlier than the Bt1 (A+W-). Arsenophonus in Bt1 delayed the first day of nymph deposition in comparison to aposymbiotic Bt1 except when reared on Rag1 + 2. For the Bt1 and Bt3 strains, symbionts did not result in a significant difference in the day they deposited the maximum number of nymphs nor was there a difference in survival or variability in number of nymphs deposited. Variability of number of aphids deposited was higher in aphids feeding on resistant plant genotypes. The impact of Arsenophonus on soybean aphid patterns of fecundity was dependent on the aphid biotype and plant genotype. Wolbachia alone had no detectable impact but may have contributed to the increased fecundity of Bt3 (A+W+). An individual based model, using data from the detached leaves experiment and with intraspecific competition removed, found patterns similar to those observed in the greenhouse and growth chamber experiments including a significant interaction between soybean genotype and aphid strain. Combining individual data with the individual based model of population growth isolated the impact of fecundity and host resistance from intraspecific competition and host health. Changes to patterns of fecundity, influenced by the composition and concentration of symbionts, may contribute to competitive interactions among aphid genotypes and influence selection on virulent aphid populations.

A descriptive analysis of COVID-19 associated mortality in Parma Province: concordance between official national mortality register provided by ISTAT (National Institute of Statistics) and local ADS (Automated Data System) real-time surveillance flow.

BACKGROUND AND AIM: The Public Health Department of the Parma Local Health Authority (AUSL) has implemented a computerized system called ADS (Automated Data System) to collect data on COVID-19 cases and related deaths, as required by the Emilia-Romagna Region and the Italian Ministry of Health, to improve the daily flow of real-time information. However, official mortality data for all causes was collected even from the National Institute of Statistics (ISTAT) through death forms that were completed by certifying doctors in each municipality. This analysis aims to verify the agreement between the data collected by ISTAT and the data collected by ADS. METHODS: The study period went from January 1st to December 31st, 2021. The population under observation consisted of residents in the province of Parma who died due to COVID-19, as identified through the ISTAT and/or ADS data flow. RESULTS: In 2021, a total of 448 deaths due to COVID-19 were reported in the Parma Province, with a median age of 83 years. The ADS system identified 408 of these deaths, whereas ISTAT certified only 347. Three hundred and seven deaths were identified by both flows. CONCLUSIONS: The survey suggests that the ADS surveillance system may have overestimated the COVID-19 mortality data compared to the ISTAT flow. The ADS has been valuable in the immediate response to emergencies, providing a more sensitive system that prioritizes the precautionary principle and enables decisions aimed at minimizing risks for vulnerable populations. However, it is not recommended for routine surveillance, as it is less reliable compared to the ISTAT flow.

Can we get out of the COVID pandemic without adequate vaccination coverage in the pediatric population?

BACKGROUND: During the first and second COVID-19 pandemic waves, children, despite susceptible to SARS-CoV-2 infection, appeared at lower risk of severe disease, hospitalization, and death than adults and the elderly. Moreover, they seemed to play a minor role in the diffusion of the virus. The aim of this manuscript is to show epidemiological surveillance on COVID-19 incidence and hospitalization in the pediatric cohort in order to explain the importance of an adequate COVID-19 vaccination coverage in the pediatric population. METHODS: All subjects with documented SARS-CoV-2 infection diagnosed in Parma, Italy, between February 21st, 2020, and January, 31st, 2022, were recruited in this epidemiological surveillance. Diagnosis of infection was established in presence of at least one respiratory specimen positive for SARS-CoV-2 nucleic acid using a validated real-time reverse-transcriptase polymerase-chain-reaction (RT-PCR) assay. RESULTS: The number of COVID-19 pediatric cases remained very low and lower than that recorded in the general population between early February 2020 and the end of October 2021, despite in the last part of this period the Delta variant emerged. On the contrary, starting from November 2021, a sharp and significant increase in COVID-19 incidence in the pediatric population was evidenced. This was detected in all the age groups, although greater in the populations aged 5-11 and 12-17 years old. Interestingly, the peak in hospitalization rate was observed in children < 5 years old, for whom COVID-19 vaccination is not approved yet. At the beginning of November 2021 among people older than 18 years of age 85.7% had completed the primary series of COVID-19 vaccine. Almost all the infants and pre-school children were susceptible. Until January 31st, 2022, 80.4% of adolescents aged 11-17 years had received at least two doses of COVID-19 vaccine and only 52.4% received the booster. Among children 5-11 years old, on January 31st, 2022, only 28.5% had received at least one vaccine dose. CONCLUSIONS: Compared with adults and the elderly, presently a greater proportion of children and adolescents is susceptible to SARS-CoV-2 and could play a relevant role for the prolongation of the COVID-19 pandemic. Only a rapid increase in vaccination coverage of the pediatric populations can effectively counter this problem.

Myocarditis Following COVID-19 Vaccine Use: Can It Play a Role for Conditioning Immunization Schedules?

Myocarditis (MYO) is a relatively uncommon inflammatory disease that involves the heart muscle. It can be a very severe disease as it can lead to the development of acute or chronic heart failure and, in a not marginal number of cases, to death. Most of the cases are diagnosed in healthy people younger than 30 years of age. Moreover, males are affected about twice as much as females. Viruses are among the most common causes of MYO, but how viral infection can lead to MYO development is not precisely defined. After COVID-19 pandemic declaration, incidence rate of MYO has significantly increased worldwide because of the SARS-CoV-2 infection. After the introduction of anti-COVID-19 vaccines, reports of post-immunization MYO have emerged, suggesting that a further cause of MYO together with the SARS-CoV-2 infection could increase the risk of heart damage during pandemic. Main aim of this study is to discuss present knowledge regarding etiopathogenesis and clinical findings of MYO associated with COVID-19 vaccine administration and whether the risk of this adverse events can modify the initially suggested recommendation for the use of COVID-19 vaccines in pediatric age. Literature analysis showed that MYO is an adverse event that can follow the COVID-19 immunization with mRNA vaccines in few persons, particularly young adults, adolescents, and older children. It is generally a mild disease that should not modify the present recommendations for immunization with the authorized COVID-19 mRNA vaccines. Despite this, further studies are needed to evaluate presently undefined aspects of MYO development after COVID-19 vaccine administration and reduce the risk of development of this kind of vaccine complication. Together with a better definition of the true incidence of MYO and the exact role of the various factors in conditioning incidence variations, it is essential to establish long-term evolution of acute COVID-19 related MYO.

Risks of SARS-CoV-2 Infection and Immune Response to COVID-19 Vaccines in Patients With Inflammatory Bowel Disease: Current Evidence.

Inflammatory bowel diseases (IBD), including Crohn's disease, ulcerative colitis, and unclassified inflammatory bowel disease, are a group of chronic, immune mediated conditions that are presumed to occur in genetically susceptible individuals because of a dysregulated intestinal immune response to environmental factors. IBD patients can be considered subjects with an aberrant immune response that makes them at increased risk of infections, particularly those due to opportunistic pathogens. In many cases this risk is significantly increased by the therapy they receive. Aim of this narrative review is to describe the impact of SARS-CoV-2 infection and the immunogenicity of COVID-19 vaccines in patients with IBD. Available data indicate that patients with IBD do not have an increased susceptibility to infection with SARS-CoV-2 and that, if infected, in the majority of the cases they must not modify the therapy in place because this does not negatively affect the COVID-19 course. Only corticosteroids should be reduced or suspended due to the risk of causing severe forms. Furthermore, COVID-19 seems to modify the course of IBD mainly due to the impact on intestinal disease of the psychological factors deriving from the measures implemented to deal with the pandemic. The data relating to the immune response induced by SARS-CoV-2 or by COVID-19 vaccines can be considered much less definitive. It seems certain that the immune response to disease and vaccines is not substantially different from that seen in healthy subjects, with the exception of patients treated with anti-tumor necrosis factor alone or in combination with other immunosuppressants who showed a reduced immune response. How much, however, this problem reduces induced protection is not known. Moreover, the impact of SARS-CoV-2 variants on IBD course and immune response to SARS-CoV-2 infection and COVID-19 vaccines has not been studied and deserves attention. Further studies capable of facing and solving unanswered questions are needed in order to adequately protect IBD patients from the risks associated with SARS-CoV-2 infection.

Description of a new species of Plutomurus Yosii (Collembola: Tomoceridae) from Georgia, Caucasus and notes on the morphology of Plutomurus birsteini Djanashvili amp; Barjadze.

Plutomurus jordanai sp. nov. from Zeda Kvilishori Cave (Tskaltubo Municipality, Imereti region, Western Georgia) is described, illustrated and differentiated from other morphologically similar species‒‒P. kelasuricus Martynova, 1969 and P. eristoi Barjadze, Baquero, Soto-Adames, Giordano Jordana, 2016. In addition, morphological characters omitted or erroneously provided in the original description of Plutomurus birsteini Djanashvili Barjadze, 2011 are described and illustrated from the specimen sampled in the type locality‒‒Sakishore Cave (Racha region, Western Georgia). An identification key to the species of the genus Plutomurus reported from the Caucasus is presented. A list of the invertebrate communities for Zeda Kvilishori and Sakishore caves is provided.

Genome scan detection of selective sweeps among biotypes of the soybean aphid, Aphis glycines, with differing virulence to resistance to A. glycines (Rag) traits in soybean, Glycine max.

Multiple biotypes of soybean aphid, Aphis glycines, occur in North America adapted for survival (virulence) on soybean, Glycine max, with one or more different resistance to A. glycines (Rag) traits. The degree of genome-wide variance between biotypes and the basis of virulence remains unknown, but the latter is hypothesized to involve secreted effector proteins. Between 167,249 and 217,750 single nucleotide polymorphisms (SNPs) were predicted from whole genome re-sequencing of A. glycines avirulent biotype 1 (B1) and virulent B2, B3 and B4 colony-derived iso-female lines when compared to the draft B1 genome assembly, Ag_bt1_v6.0. Differences in nucleotide diversity indices (π) estimated within 1000 bp sliding windows demonstrated that 226 of 353 (64.0%) regions most differentiated between B1 and ≥ 2 virulent biotypes, representing < 0.1% of the 308 Mb assembled genome size, are located on 15 unordered scaffolds. Furthermore, these 226 intervals were coincident and show a significant association with 326 of 508 SNPs with significant locus-by-locus FST estimates between biotype populations (r = 0.6271; F1,70 = 45.36, P < 0.001) and genes showing evidence of directions selection (πN/πS > 2.0; r = 0.6233; F1,70 = 50.20, P < 0.001). A putative secreted effector glycoprotein is encoded in proximity to genome intervals of low estimated π (putative selective sweep) within avirulent B1 compared to all three virulent biotypes. Additionally, SNPs are clustered in or in proximity to genes putatively involved in intracellular protein cargo transport and the regulation of secretion. Results of this study indicate that factors on a small number of scaffolds of the A. glycines genome may contribute to variance in virulence towards Rag traits in G. max.

Soybean aphid biotype 1 genome: Insights into the invasive biology and adaptive evolution of a major agricultural pest.

The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae) is a serious pest of the soybean plant, Glycine max, a major world-wide agricultural crop. We assembled a de novo genome sequence of Ap. glycines Biotype 1, from a culture established shortly after this species invaded North America. 20.4% of the Ap. glycines proteome is duplicated. These in-paralogs are enriched with Gene Ontology (GO) categories mostly related to apoptosis, a possible adaptation to plant chemistry and other environmental stressors. Approximately one-third of these genes show parallel duplication in other aphids. But Ap. gossypii, its closest related species, has the lowest number of these duplicated genes. An Illumina GoldenGate assay of 2380 SNPs was used to determine the world-wide population structure of Ap. Glycines. China and South Korean aphids are the closest to those in North America. China is the likely origin of other Asian aphid populations. The most distantly related aphids to those in North America are from Australia. The diversity of Ap. glycines in North America has decreased over time since its arrival. The genetic diversity of Ap. glycines North American population sampled shortly after its first detection in 2001 up to 2012 does not appear to correlate with geography. However, aphids collected on soybean Rag experimental varieties in Minnesota (MN), Iowa (IA), and Wisconsin (WI), closer to high density Rhamnus cathartica stands, appear to have higher capacity to colonize resistant soybean plants than aphids sampled in Ohio (OH), North Dakota (ND), and South Dakota (SD). Samples from the former states have SNP alleles with high FST values and frequencies, that overlap with genes involved in iron metabolism, a crucial metabolic pathway that may be affected by the Rag-associated soybean plant response. The Ap. glycines Biotype 1 genome will provide needed information for future analyses of mechanisms of aphid virulence and pesticide resistance as well as facilitate comparative analyses between aphids with differing natural history and host plant range.

Analysis of the extent of synteny and conservation in the gene order in aphids: A first glimpse from the Aphis glycines genome.

In the last decade several insect genomes have been sequenced, but for most the chromosomal mapping of the identified scaffolds/annotated genes is not available. The lack of this information makes it difficult to analyse various genetic aspects, including the presence of genome rearrangements and the extent of synteny within and across species. We mapped five multigenic DNA families (major and minor rDNAs, histone gene cluster, esterases and carotenoid desaturases) and seven scaffolds corresponding to 9 Mb of the soybean aphid, Aphis glycines, genome and identified loci spanning the four soybean aphid chromosomes. A comparative analysis of the localization of the annotated A. glycines genes with respect to the peach potato aphid, Myzus persicae, and the fly, Drosophila melanogaster, evidenced a lower degree of synteny between the two aphid species than in the aphid-fly comparison. Only 1.4 genes per syntenic block were observed in aphids in contrast to 2.3 genes per block in flies. This higher chromosomal rearrangement rate in aphids could be explained considering that they possess holocentric chromosomes that can favour the stabilization and inheritance of chromosomal rearrangements. Lastly, our experiments did not detect the presence of chimeric assemblies in the newly available A. glycines biotype 1 genome, differently from what reported in assembled genome of other aphid species, suggesting that chromosomal mapping can be used to ascertain the quality of assembled genomes.

Description of soybean aphid (Aphis glycines Matsumura) mitochondrial genome and comparative mitogenomics of Aphididae (Hemiptera: Sternorrhyncha).

The complete mitochondrial genome of the soybean aphid (Aphis glycines Matsumura), a major agricultural pest in the world, is described for the first time, which consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, as well as a large repeat region between tRNA-Glu and tRNA-Phe, and an AT-rich control region. The 17,954 bp mtgenome is the largest reported from the family Aphididae, and its gene order follows the ancestral insect mtgenome except for the repeat region, which contains a 195 bp unit repeated 11.9 times, representing the highest reported repeats among the known aphid mtgenomes to date. A new molecular phylogeny of Aphidae is reconstructed based on all available aphid mtgenomes, and it is shown that the mtgenome data can robustly resolve relationships at the subfamily level, but do not have sufficient phylogenetic information to resolve deep relationships. A phylogeny-based comparative analysis of mtgenomes has been performed to investigate the evolution of the repeat region between tRNA-Glu and tRNA-Phe. So far, among aphids, 13 species are known to have this repeat region of variable lengths, and a phylogenetic analysis of the repeat region shows that a large proportion of the sequences are conserved across the phylogeny, suggesting that the repeat region evolved in the most recent common ancestor of Aphidinae and Eriosomatinae, and that it has gone through numerous episodes of lineage-specific losses and expansions. Combined together, this study provides novel insights into how the repeat regions have evolved within aphids.

Two new species of Plutomurus Yosii (Collembola, Tomoceridae) from the Caucasus.

Two new species of Plutomurus, P. pichkhaiai sp. nov. from Garakha and Letsurtsume caves and P. shurubumuensis sp. nov. from Shurubumu Cave (Chkhorotsku district, Western Georgia) are described, and illustrated. The new species are very similar to P. kelasuricus from the Tsebelda karst massif formation in Apkhazeti, Georgia, but differ in having two inner spine-like chaetae on the inner edge of the hind tibiotarsus (only one in P. kelasuricus) and in occupying different, isolated cave formations separated by a geographic distance of nearly a 100 km. A key to the species of Plutomurus with 6 prelabral chaetae is provided.

New diagnosis for species of Plutomurus Yosii (Collembola, Tomoceridae), with descriptions of two new species from Georgian caves.

Two new species of the genus Plutomurus, P. revazi sp. nov. from Prometheus and Satsurblia caves and P. eristoi sp. nov. from Satevzia Cave are described, illustrated and differentiated from other morphologically closely related species. A high variability in the number of teeth in the claw, unguiculus and mucro of P. revazi sp. nov. demonstrate that these characters are not useful for species diagnosis. However, dorsal chaetotaxy was shown to be stable character for this purpose. Analysis of DNA sequences for the COI and 28S genes is congruent with species-level groups delimited by chaetotaxy, and provide additional support for chaetotaxy as the most reliable morphological character system to distinguish species in Plutomurus. A key to species of the genus Plutomurus found in Georgia is provided, which for the first time includes characters of the macrochaetotaxy.

Congruence between cytochrome oxidase I (COI) and morphological data in Anuraphis spp. (Hemiptera, Aphididae) with a comparison between the utility of the 5' barcode and 3' COI regions.

The discrimination of species in the genus Anuraphis is particularly difficult due to the overlap of morphological characters. In this study, we used the 5' (barcode) and 3' regions of cytochrome oxidase I (COI) to test their utility in the identification of species in this genus as well as closely related species. Both regions were useful to discriminate all the species tested. However the non-barcode 3' region resulted in higher resolution and support for species relationships when the data were analyzed using both Maximum Likelihood and MrBayes. We propose the development of an integrated database that encompasses morphological, molecular, life-cycle, host plant and bibliographic information to facilitate and increase the accuracy of aphid identification.

Taxonomic review and phylogenetic analysis of fifteen North American Entomobrya (Collembola, Entomobryidae), including four new species.

The chaetotaxy of 15 species of eastern North American Entomobrya is redescribed in order to determine potential characters for the diagnosis of cryptic lineages and evaluate the diagnostic and phylogenetic utility of chaetotaxy. As a result, four new species (Entomobrya citrensis Katz & Soto-Adames, sp. n., Entomobrya jubata Katz & Soto-Adames, sp. n., Entomobrya neotenica Katz & Soto-Adames, sp. n. and Entomobrya unifasciata Katz & Soto-Adames, sp. n.) are described, and new diagnoses are provided for Entomobrya assuta Folsom, Entomobrya atrocincta Schött, Entomobrya decemfasciata (Packard), Entomobrya ligata Folsom, Entomobrya multifasciata (Tullberg), and Entomobrya quadrilineata (Bueker). Furthermore, previously undocumented levels of intraspecific variation in macrosetal pattern are reported, tempering the exclusive use of chaetotaxy for species delimitation. Phylogenetic relationships, estimated using both morphological and molecular data, indicate that Entomobrya is likely paraphyletic. The phylogenies also suggest that unreliable character homology, likely fostered by Entomobrya's profusion of macrosetae, may limit the phylogenetic utility of chaetotaxy in groups characterized by an abundance of dorsal macrosetae.

Invertebrates associated with a horizontal-flow, subsurface constructed wetland in a northern climate.

Wetlands function as buffers between terrestrial and aquatic ecosystems, filtering pollutants generated by human activity. Constructed wetlands were developed to mimic the physical and biological filtering functions of natural systems for the treatment of human and animal waste under controlled conditions. Previous studies on the effect of constructed wetlands on native invertebrate populations have concentrated almost exclusively on mosquitoes. Here, we present the first study investigating the relationship between vegetation cover and aeration regime, and the diversity and abundance of nematodes and springtails (Collembola) in a constructed wetland designed to treat dairy farm wastewater in northwestern Vermont. We investigated four treatment cells differing in aeration regime and vegetation cover, but equally overlaid by a layer of compost to provide insulation. Analysis showed that nematodes were most abundant in the nonplanted and nonaerated cells, and that bacterivorous nematodes dominated the community in all cells. Springtails were found to be most numerous in the planted and nonaerated cells. We hypothesize that the vegetation provided differing environmental niches that supported a more diverse system of bacteria and fungi, as well as offering protection from predators and inclement weather. Nematodes were likely imported with the original compost material, while springtails migrated into the cells either via air, water, or direct locomotion.

Molecular and morphological differentiation between Aphis gossypii Glover (Hemiptera, Aphididae) and related species, with particular reference to the North American Midwest.

The cotton aphid, Aphis gossypii, is one of the most biologically diverse species of aphids; a polyphagous species in a family where most are host specialists. It is economically important and belongs to a group of closely related species that has challenged aphid taxonomy. The research presented here seeks to clarify the taxonomic relationships and status of species within the Aphid gossypii group in the North American Midwest. Sequences of the mitochondrial cytochrome oxidase 1 (COI), nuclear elongation factor 1-α (EF1-α), and nuclear sodium channel para-type (SCP) genes were used to differentiate between Aphid gossypii and related species. Aphis monardae, previously synonymised with Aphid gossypii, is re-established as a valid species. Phylogenetic analyses support the close relationship of members of the Aphid gossypii group native to North America (Aphid forbesi, Aphid monardae, Aphid oestlundi, Aphid rubifolii, and Aphid rubicola), Europe (Aphid nasturtii, Aphid urticata and Aphid sedi), and Asia (Aphid agrimoniae, Aphid clerodendri, Aphid glycines, Aphid gossypii, Aphid hypericiphaga, Aphid ichigicola, Aphid ichigo, Aphid sanguisorbicola, Aphid sumire and Aphid taraxicicola). The North American species most closely related to Aphid gossypii are Aphid monardae and Aphid oestlundi. The cosmopolitan Aphid gossypii and Aphid sedi identified in the USA are genetically very similar using COI and EF1-α sequences, but the SCP gene shows greater genetic distance between them. We present a discussion of the biological and morphological differentiation of these species.

Aphis (Hemiptera: Aphididae) species groups found in the Midwestern United States and their contribution to the phylogenetic knowledge of the genus.

A phylogeny of the genus Aphis Linnaeus, 1 758 was built primarily from specimens collected in the Midwest of the United States. A data matrix was constructed with 68 species and 41 morphological characters with respective character states of alate and apterous viviparous females. Dendrogram topologies of analyses performed using UPGMA (Unweighted Pair Group Method with Arithmetic Mean), Maximum Parsimony and Bayesian analysis of Cytochrome Oxidase I, Elongation Factor 1-α and primary endosymbiont Buchnera aphidicola 16S sequences were not congruent. Bayesian analysis strongly supported most terminal nodes of the phylogenetic trees. The phylogeny was strongly supported by EF1-α, and analysis of COI and EF1-α molecular data combined with morphological characters. It was not supported by single analysis of COI or Buchnera aphidicola 16S. Results from the Bayesian phylogeny show 4 main species groups: asclepiadis, fabae, gossypii, and middletonii. Results place Aphis and species of the genera Protaphis Börner, 1952, Toxoptera Koch, and Xerobion Nevsky, 1928 in a monophyletic clade. Morphological characters support this monophyly as well. The phylogeny shows that the monophyletic clade of the North American middletonii species group belong to the genus Protaphis: P. debilicornis (Gillette & Palmer, 1929), comb. nov., P. echinaceae (Lagos and Voegtlin, 2009), comb. nov., and P. middletonii (Thomas, 1879). The genus Toxoptera should be considered a subgenus of Aphis (stat. nov.). The analysis also indicates that the current genus Iowana Frison, 1954 should be considered a subgenus of Aphis (stat. nov.).

The common ecotoxicology laboratory strain of Hyalella azteca is genetically distinct from most wild strains sampled in eastern North America.

The amphipod Hyalella azteca is commonly used as a model for determining safe concentrations of contaminants in freshwaters. The authors sequenced the mitochondrial cytochrome c oxidase subunit I (COI) gene for representatives of 38 populations of this species complex from US and Canadian toxicology research laboratories and eastern North American field sites to determine their genetic relationships. With 1 exception, all US and Canadian laboratory cultures sampled were identified as conspecific. In 22 wild populations spanning 5 US states and 1 Canadian province, the commonly occurring laboratory species was found only in northern Florida, USA. Therefore, the diversity of the H. azteca species complex detected in the wild is not accurately represented in North American laboratories, questioning the reliability of H. azteca cultures currently in use to accurately predict the responses of wild populations in ecotoxicological assays. The authors also examined the utility of different COI nucleotide fragments presently in use to determine phylogenetic relationships in this group and concluded that saturation in DNA sequences leads to inconsistent relationships between clades. Amino acid sequences for COI were not saturated and may allow a more accurate phylogeny estimate. Hyalella azteca is crucial for developing water-quality regulations; therefore, laboratories should know and standardize the strain(s) they use to confidently compare toxicity tests across laboratories and determine whether they are an appropriate surrogate for their regions.

Bellisotoma, a new genus of Isotomidae from North America (Hexapoda, Collembola).

A new genus of Isotomidae, Bellisotoma gen. n., is described. The new genus is a member of the Proisotoma genus complex and is characterized by a combination of having a bidentate mucro with wide dorsal lamellae that join clearly before the end of mucronal axis without forming a tooth and one strong ventral rib with basal notch that articulates with dens; having abundant chaetotaxy on both faces of dens; and abundant tergal sensilla. Bellisotoma gen. n. shows a furcula adapted to a neustonic mode of life, and may be a Isotopenola-like derivative adapted to neustonic habitats. Subisotoma joycei Soto-Adames & Giordano, 2011 and Ballistura ewingi James, 1933 are transferred to the new genus.