Comparison of 3D-Printed Single Crown Outcomes Among Different Computer-Aided Design Software Programs.

PURPOSE: Low-cost resin 3D printers have been used to produce affordable interim single crowns in public and private dental practices. The purpose of this study was to assess the impact of different computer-aided design (CAD) software programs on 3D trueness, microscopic marginal and internal gaps, time to design, and interproximal contacts of low-cost 3D-printed single crowns. MATERIALS AND METHODS: This in vitro study was performed on a total of 90 standardized resin-prepared teeth adapted to a dental manikin. For comparison among CAD software programs, 45 tooth preparations received 3D-printed crowns designed with one of three CAD software programs by an experienced technician and identified as groups TRIOS (n = 15), EXOCAD (n = 15), and ZZ (Zirkonzahn; n = 15). To assess interoperator reproducibility, 15 additional crowns were designed by a dental clinician (group ZZ-DENT) and 15 by a dental prosthetic technician (group ZZ-PROS), both with basic 1-week CAD/CAM training. Finally, as a control group, 15 crowns were milled using a high-end five-axis milling device (group ZZ-CONTROL). Statistically significant differences for 3D trueness, microscopic gaps, time to design, and interproximal contacts among groups were assessed with the Kruskal-Wallis test. RESULTS: No statistically significant differences in 3D trueness or marginal or internal gaps were found, either among different software programs or CAD operators (P > .05). However, Group TRIOS took significantly longer to design than EXOCAD and ZZ groups (P = .001). Less-experienced operators were significantly outperformed in time and interproximal contacts (P = .001) by the CAD technician using the same software program. Finally, control milled crowns (ZZ-CONTROL) significantly outperformed the respective 3D-printed copies (ZZ) in all assessed variables (P < .001). CONCLUSIONS: Different CAD software programs may affect the time required to design, but they do not significantly affect clinical outcomes of low-cost 3D-printed resin crowns if designed by an experienced CAD technician.

The oriental hornet (Vespa orientalis) as a potential vector of honey bee's pathogens and a threat for public health in North-East Italy.

BACKGROUND: Oriental hornets are large predatory hymenoptera that occur in the southern part of Asia and the southeastern Mediterranean. Among many pests of bee colonies, Vespa orientalis was recorded to be one of the most destructive. OBJECTIVES: The aim of this study was to: (1) monitor the presence of pathogens carried by V. orientalis that could potentially threaten honey bees and public health; (2) describe the hornet's predatory behavior on honey bee colonies and (3) collect the medical history of a V. orientalis sting suffered by a 36-year-old woman. METHODS: Observations of V. orientalis predatory behavior and the catches of hornets for parasitological and microbiological examination, using molecular and bacteriological analyses, were carried out in three experimental apiaries, both in spring in order to capture the foundress queens and during the summer to capture the workers. Furthermore, the medical history and photographic documentation of a V. orientalis sting suffered by a 36-year-old woman have been collected. RESULTS: The results obtained highlight that V. orientalis is capable of causing serious damage to beekeeping by killing bees, putting under stress the honey bee colonies and by potentially spreading honey bee pathogens among apiaries. These hornets may also become a public health concern, since they are capable of inflicting multiple, painful stings on humans. CONCLUSIONS: Only the development of an Integrated Management Control Program will be able to contain the negative effects of anomalous population growth and the potentially negative impact on honey bees and public health of V. orientalis.

Beneficial Bacteria and Plant Extracts Promote Honey Bee Health and Reduce Nosema ceranae Infection.

The research aims to give new insights on the effect of administering selected bacterial strains, isolated from honey bee gut, and/or a commercial plant extract blend (HiveAlive®) on Nosema ceranae. Analyses were first performed under laboratory conditions such as different infective doses of N. ceranae, the effect of single strains and their mixture and the influence of pollen administration. Daily survival and feed consumption rate were recorded and pathogen development was analysed using qPCR and microscope counts. Biomarkers of immunity and physiological status were also evaluated for the different treatments tested using one bacterial strain, a mixture of all the bacteria and/or a plant extract blend as treatments. The results showed an increase of abaecin transcript levels in the midgut of the honey bees treated with the bacterial mixture and an increased expression of the protein vitellogenin in the haemolymph of honey bees treated with two separate bacterial strains (Bifidobacterium coryneforme and Apilactobacillus kunkeei). A significant effectiveness in reducing N. ceranae was shown by the bacterial mixture and the plant extract blend regardless of the composition of the diet. This bioactivity was seasonally linked. Quantitative PCR and microscope counts showed the reduction of N. ceranae under different experimental conditions. The antiparasitic efficacy of the treatments at field conditions was studied using a semi-field approach which was adapted from research on insecticides for the first time, to analyse antiparasitic activity against N. ceranae. The approach proved to be reliable and effective in validating data obtained in the laboratory. Both the mixture of beneficial bacteria and its association with Hive Alive® are effective in controlling the natural infection of N. ceranae in honey bee colonies.

The Tubulifera (Hexapoda, Thysanoptera) of the Maltese Islands.

This work records the presence of 13 species of tubuliferan thrips from the Maltese Islands. Eleven of these species, namely Bolothripsdentipes, B.insularis, Priesneriellamavromoustakisi, Gynaikothripsuzeli, Haplothripsacanthoscelis, H.aculeatus, H.setiger, H.tritici, Karnyothripsflavipes, Liothripsreuteri and Neoheegeriadalmatica are new records for the Maltese Islands. Two species: Gynaikothripsficorum and Karnyothripsflavipes can be described as subcosmopolitan in distribution, another three species: Haplothripsaculeatus, H.setiger and H.tritici are distributed across the Holarctic and Palaearctic regions, while a further seven: Bolothripsdentipes, B.insularis, Haplothripsacanthoscelis, Liothripsoleae, L.reuteri, Neoheegeriadalmatica and Priesneriellamavromoustakisi have a European and/or Mediterranean distribution. Gynaikothripsficorum and G.uzeli are considered as alien species. A key to the Tubulifera of the Maltese Islands as well as chorological data for these recorded species are provided in this work.

The Ancient Olive Trees (Olea europaea L.) of the Maltese Islands: A Rich and Unexplored Patrimony to Enhance Oliviculture.

A prospecting campaign in the Maltese Islands has ensured the survival of several ancient olive trees (Olea europaea L.), genetically distant from known cultivars. Most of these plants were abandoned or partially cultivated. A two-year evaluation of fruit characteristics and compositions was performed on samples collected from the main representatives of these indigenous genotypes. Analyses were carried out using Gas Chromatography, High-Performance Liquid Chromatography and Near Infrared Spectrometry. Among the fruit samples, a wide range of variations was observed. Some of the genotypes showed fruit traits suitable for table olive production. This is the case of samples with a pulp/pit ratio higher than four, such as 1Wardija, 1Caritas, 1Plattini, 1Bingemma Malta and 3Loretu, whilst 1Bidni, 1Mellieha, 2Qnotta, 3Loretu, 1Bingemma Malta and 1Caritas were suitable for dual purpose. The total phenol content ranged from 6.3 (1Wardija) to 117.9 (2Mtarfa) g/kg of fresh pulp. The average percentage of MUFA was quite low for most of the varieties. These genotypes, which presumably originated in the Maltese Islands and are well adapted to the local pedo-climatic conditions, are being propagated for the following evaluation of their bio-agronomical performance (production, suitability to intensive cultivation, environmental sustainability, product quality, etc.). The purpose is to select, among these local genotypes, the most outstanding varieties, in terms of phenolic and FA profile and agronomical potential, to spread into cultivation, thereby contributing to an increase in the quality of the local table and olive oil production, strongly linked to the territory.

Environment or genetic isolation? An atypical intestinal microbiota in the Maltese honey bee Apis mellifera spp. ruttneri.

Introduction: Apis mellifera evolved mainly in African, Asian, and European continents over thousands of years, leading to the selection of a considerable number of honey bees subspecies that have adapted to various environments such as hot semi-desert zones and cold temperate zones. With the evolution of honey bee subspecies, it is possible that environmental conditions, food sources, and microbial communities typical of the colonized areas have shaped the honey bee gut microbiota. Methods: In this study the microbiota of two distinct lineages (mitochondrial haplotypes) of bees Apis mellifera ruttneri (lineage A) and Apis mellifera ligustica and carnica (both lineage C) were compared. Honey bee guts were collected in a dry period in the respective breeding areas (the island of Malta and the regions of Emilia-Romagna and South Tyrol in Italy). Microbial DNA from the honey bee gut was extracted and amplified for the V3-V4 regions of the 16S rRNA gene for bacteria and for ITS2 for fungi. Results: The analyses carried out show that the Maltese lineage A honey bees have a distinctive microbiota when compared to Italian lineage C honey bees, with the most abundant genera being Bartonellaceae and Lactobacillaceae, respectively. Lactobacillaceae in Maltese Lineage A honey bees consist mainly of Apilactobacillus instead of Lactobacillus and Bombilactobacillus in the lineage C. Lineage A honey bee gut microbiota also harbors higher proportions of Arsenophonus, Bombella, Commensalibacter, and Pseudomonas when compared to lineage C. Discussion: The environment seems to be the main driver in the acquisition of these marked differences in the gut microbiota. However, the influence of other factors such as host genetics, seasonality or geography may still play a significant role in the microbiome shaping, in synergy with the environmental aspects.

The Intranidal Myrmecophiles of the Maltese Islands with Notes on Messor Nests as Repositories of Biodiversity.

The intranidal myrmecophilous arthropod fauna of the Maltese Islands is reviewed. Thirty species from nine orders are found to be obligate myrmecophiles, of which four species are recorded from the Maltese archipelago for the first time: Phrurolithus sp. (Araneae: Phrurolithidae), Pogonolaelaps canestrinii (Berlese, 1904), Gymnolaelaps messor Joharchi, Halliday, Saboori & Kamali, 2011 and G. myrmecophilus (Berlese, 1892) (Mesostigmata: Laelapidae). Phrurolithus also represents the first record of the family Phrurolithidae in Malta. Notes on the biology and local distribution of each species are provided, including ant-myrmecophile associations, of which two appear to be previously unknown: the occurrence of Smynthurodes betae Westwood, 1849 (Hemiptera: Aphididae) in the nest of Plagiolepis pygmaea (Latreille, 1798) and Phrurolithus in the nest of Pheidole pallidula (Nylander, 1849). Fourteen additional species are found to be either only occasionally myrmecophilic, accidental ant-guests or potentially myrmecophilous, the latter remaining ambiguous due to a lack of knowledge of their biology. Of these, the family Caeculidae (Arachnida: Trombidiformes) represents a new record for the Maltese Islands, on the basis of Microcaeculus sp. occurring in a nest of Camponotus barbaricus Emery, 1905. Preliminary results indicate that Messor nests may be repositories of considerable myrmecophile diversity, with the most unique symbionts.

Patient Reported Outcomes on Different Occlusal Schemes in Complete Denture Wearers.

PURPOSE: To compare patient-reported outcomes among balanced, lingualized, and monoplane occlusal schemes in relation to edentulous jaw classifications. MATERIALS AND METHODS: This randomized controlled trial was conducted in edentulous patients receiving new complete dentures using balanced, lingualized, or monoplane occlusal schemes. Demographic variables, bone ridge quantity, number of adjustments required after denture insertion, and satisfaction and quality of life (QoL) indices (ie, the Denture Satisfaction Questionnaire [DSQ] and General Oral Health Assessment Index [GOHAI], respectively) were assessed at 1, 2, 4, 8, 12, and 52 weeks. Within-group comparisons at different time points were carried out with Brunner-Langer nonparametric analysis. Furthermore, Kruskal-Wallis test was used to compare distributions of ordinal or continuous variables among the three occlusal scheme groups. RESULTS: A total of 60 subjects (mean age: 68.1 ± 11.1 years; 56.7% men and 43.3% women) were analyzed. All three groups presented significant improvements in DSQ and GOHAI scores between denture insertion and the 1-year follow-up appointment (P < .001). There were no statistical differences in the distribution of demographic variables (eg, age, gender, years edentulous, and age of existing dentures) or of bone ridge classifications among the three groups. Similarly, there were no statistical differences in ridge classifications or in the DSQ and GOHAI values among the three groups for both the maxilla and mandible (P > .05) over the 52-week follow-up. On the other hand, the number of cases requiring denture adjustments was significantly lower in the lingualized scheme group, as compared to the two other groups (P = .034). CONCLUSION: Within the limitations of this study, the present findings suggest that the occlusal scheme for posterior teeth did not influence patient-reported subjective outcomes. However, the lingualized occlusal scheme required significantly fewer adjustments.

Authoritative subspecies diagnosis tool for European honey bees based on ancestry informative SNPs.

BACKGROUND: With numerous endemic subspecies representing four of its five evolutionary lineages, Europe holds a large fraction of Apis mellifera genetic diversity. This diversity and the natural distribution range have been altered by anthropogenic factors. The conservation of this natural heritage relies on the availability of accurate tools for subspecies diagnosis. Based on pool-sequence data from 2145 worker bees representing 22 populations sampled across Europe, we employed two highly discriminative approaches (PCA and FST) to select the most informative SNPs for ancestry inference. RESULTS: Using a supervised machine learning (ML) approach and a set of 3896 genotyped individuals, we could show that the 4094 selected single nucleotide polymorphisms (SNPs) provide an accurate prediction of ancestry inference in European honey bees. The best ML model was Linear Support Vector Classifier (Linear SVC) which correctly assigned most individuals to one of the 14 subspecies or different genetic origins with a mean accuracy of 96.2% ± 0.8 SD. A total of 3.8% of test individuals were misclassified, most probably due to limited differentiation between the subspecies caused by close geographical proximity, or human interference of genetic integrity of reference subspecies, or a combination thereof. CONCLUSIONS: The diagnostic tool presented here will contribute to a sustainable conservation and support breeding activities in order to preserve the genetic heritage of European honey bees.

Patient-based outcomes with conventional or mini-implants immediately loaded with locator-retained mandibular overdentures: A cohort study.

BACKGROUND: Little is known on the effect of varying implant diameters, especially with mini implants (ie, less than 3 mm in diameter), on oral health-related quality of life (OHrQoL). PURPOSE: To compare OHrQoL and satisfaction in patients with mandibular overdentures immediately retained by either two conventional or two mini-implants. MATERIALS AND METHODS: Edentulous patients receiving immediately loaded overdentures retained by Locators on either two conventional diameter (4.1 mm) or two mini (2.9 mm or less) implants were selected based on available buccal-lingual ridge width in the intraforaminal area. Two questionnaires were used (Oral Health Impact Profile-14 [OHIP-14]; and Denture Satisfaction Questionnaire [DSQ]) to determine OHrQoL and overall denture satisfaction. Questionnaires were filled out at six different time points up to a 1-year follow-up. Mann-Whitney U test was used for group comparisons. Friedman and Wilcoxon tests were used to identify changes within group along the time points. Correlation between OHIP-14 and DSQ was assessed with Spearman test. RESULTS: A total of 48 patients were analyzed and equally distributed to each group. The conventional group presented a significantly smaller change of OHIP functional score from the baseline to the first week of follow-up after surgery (P = .017). In addition, total DSQ scores were significantly higher for the conventional group at 12 weeks (P = .022) and there was a significant difference between groups in satisfaction with mandibular prosthesis at 24 weeks (P = .034). Correlation between OHIP-14 and DSQ was not significant (P > .05). Individual results of each group (ie, within group analysis) over all assessed time points revealed a significant OHrQoL (P = .001 for conventional, P = .006 for mini-implants) and satisfaction (P < .001 for both groups) improvement in both groups. CONCLUSION: Mandibular overdentures retained by two conventional or mini-implants lead to a significant and comparable improvements in OHrQoL and satisfaction over a 1-year follow-up.

Maintenance and risk factors for fractures of overdentures using immediately loaded conventional diameter or mini implants with Locator abutments: A cohort study.

BACKGROUND: Fractures in mandibular implant-retained overdentures are a common complication. However, little is known on the related risk factors and outcome differences when using two conventional diameter or two mini implants. PURPOSE: The purpose of this study was first, to evaluate the required maintenance and complications with the overdentures and second, to analyze risk factors for overdenture fractures. MATERIALS AND METHODS: This cohort study was conducted in edentulous patients with complete dentures. Patients received either two conventional (4.1 mm in diameter) and two mini (2.9 mm or less in diameter) implants, based on available buccal-lingual ridge width. All implants were immediately loaded with mandibular overdentures retained by Locator abutments. The number of prosthodontic after care visits (scheduled and unscheduled) were recorded and compared between the two implant diameter groups. Fracture occurrence was the primary outcome variable. Risk estimates were presented as odds ratios (ORs) with 95% confidence intervals (CIs). The ORs were adjusted for potential clinical confounders (ie, necessity of relining, matrix recapture, abutment loosening, implant diameter, height of the Locator, and retention force). RESULTS: A total of 50 edentulous patients were analyzed. One conventional diameter and three mini implants failed within a 1-year follow-up period. Prosthetic maintenance requirements for overdentures on both implant diameter groups were comparable. A total of 12 overdenture fractures (four in the mini implant group and eight in the conventional diameter group) occurred. Adjusted OR (AOR) analysis showed a significant association between abutment loosening and overdenture fracture (AOR = 12.00, 95% CI = 1.11-129.45; P = .041). CONCLUSION: Within the limitations of this study, the present findings suggest that implant diameter does not affect number of prosthetic maintenance and complications, and that abutment loosening is a risk factor for overdenture fractures, regardless of the implant diameter used.

Immediately loaded mini-implants supporting mandibular overdentures: A one-year comparative prospective cohort study.

BACKGROUND: Little is known about differences between mini-implants and conventional immediately loaded implants for overdentures. OBJECTIVES: To compare clinical outcomes using two immediately loaded conventional or mini-implants for mandibular overdentures. MATERIALS AND METHODS: Edentulous patients receiving either conventional (4.1 mm) or mini-implants (2.9 mm or less), based on available bone width were analyzed. All implants were immediately loaded with mandibular overdentures installed using locator attachments. Digital periapical radiographs for measuring marginal bone loss and clinical outcomes (ie, periodontal probing, plaque, and bleeding indices) were assessed at 1, 3, 6, and 12-month follow-up periods. RESULTS: Fifty patients (25 receiving conventional implants-12 females, mean age of 65.3 ± 7.3 years; and 25 receiving mini-implants-11 females, mean age of 66.8 ± 8.1 years) was analyzed. Peak insertion torque (P = .001) and bone loss (P = .02), as well as change in plaque (P = .02) and bleeding (P = .04) indices at 12 months differed significantly between groups. Furthermore, linear regression revealed the height of the locator as a risk factor for bone loss (P = .038). CONCLUSIONS: The present findings suggest that two mini-implants are significantly more susceptible to bone loss after immediate loading, for which the height of locator might be considered a risk factor.

Application of ATR-FT-MIR for Tracing the Geographical Origin of Honey Produced in the Maltese Islands.

Maltese honey has been produced, marketed, and sold as an exclusive local gourmet food product for countless years. Yet, thus far, no study has evaluated the individuality of this local food product. The evaluation of the parameters and properties which characterise the provenance and floral source of honey have been the subject of various studies worldwide, owing to the price and potential beneficial properties of this food product. Models analysing the potential of attenuated total reflection mid-infrared (ATR-FT-MIR) spectroscopy in discriminating and classifying local honey from that of foreign origin were investigated using 21 Maltese honey samples and 49 honey samples collected from abroad (Sicily, Greece, Sweden, Italy, France, Estonia and other samples of mixed geographical origin). Through a combination of spectroscopic techniques, spectral transformations, variable selection and partial least squares discriminant analysis (PLS-DA), chemometric models which successfully classified the provenance of local and non-local honey were developed. The results of these models were also corroborated with other classification and pattern recognition techniques, such as linear discriminate analysis (LDA), support vector machines (SVM) and feed-forward artificial neural networks (FF-ANN).

A new species of Faronus Aubé, 1844, endemic to Malta (Coleoptera, Staphylinidae, Pselaphinae).

Faronus rica sp. nov. endemic to Malta is described and illustrated, and placed in the Faronus hispanus species group. Faronus rica sp. nov. is closely related to F. siculus Fiori, 1913, an endemic species to Sicily, and they can be distinguished based on morphological features highlighted in the present work.

Braconid and ichneumonid (Hymenoptera) parasitoid wasps of Lepidoptera from the Maltese Islands.

Fourteen species of Ichneumonidae are here recorded from the Maltese Islands. Of these, all were reared from Lepidoptera hosts with the exception of Netelia (Paropheltes) inedita (Kokujev) which was collected from a malaise trap. Of these, the following species (or genera) are here reported for the first time from the Maltese Islands: Chirotica meridionalis Horstmann, Gelis carbonarius (de Stefani), G. exareolatus (FÓ§rster), G. seyrigi Ceballos, Glypta sp., Meloboris sp., Netelia (Paropheltes) inedita (Kokujev), Ophion obscuratus Fabricius and Orthizema sp. Twenty-five species of Braconidae are also here reported from Lepidoptera hosts with the exception of Homolobus (Phylacter) meridionalis van Achterberg which was collected from a malaise trap. Of these, the following species (or genera) represent new records for the Maltese Islands: Apanteles metacarpalis (Thomson), Ascogaster sp., Clinocentrus excubitor (Haliday) [previously misidentified as C. exsertor (Nees) by Papp (2015)], Cotesia vestalis (Haliday) [previously misidentified as C. ruficrus (Haliday) by Papp (2015)], Dolichogenidea britannica (Wilkinson), Homolobus (Phylacter) meridionalis van Achterberg, Iconella ? meruloides (Nixon), Lysitermus tritoma (Boucek), Lysitermus suecius (Hedqvist), Microgaster messoria Haliday, Meteorus pulchricornis (Wesmael), Pholetesor circumscriptus (Nees) [previously misidentified as P. bicolor (Nees) by Papp (2015)] and Spathius pedestris Wesmael. Thus previous records of Clinocentrus exsertor and Pholetesor bicolor from Malta were found to be based on misidentifications and are here excluded from the braconid fauna of Malta. Maltese records of Cotesia abjecta (Marshall) and Cotesia jucunda (Marshall) by Papp (2015) were found to be misidentifications and should both refer to C. glomerata (Linnaeus). Thus, both Cotesia abjecta and Cotesia jucunda are also here removed from the braconid fauna of Malta. The record of Cotesia tibialis (Curtis) by Papp (2015) was also based on a misidentification and should be attributed to C. ruficrus (Haliday). Thus, C. tibialis is also removed from the braconid fauna of Malta.

Colaphellus palaestinus Achard, a new leaf-beetle for Europe (Coleoptera, Chrysomelidae, Chrysomelinae).

Colaphellus palaestinus Achard, an alien invasive species is here reported for the first time for Europe. It was found for the first time in Malta in November 2017, and the year after thousands of individuals were observed in Malta with many photographs posted in social media and local news. Global distribution of this species and information on closely related species is also provided here. Colaphellus zarudnyi Medvedev is probably a synonym of C. palaestinus.

New records of Chalcidoidea (Hymenoptera) from the Maltese Islands with an updated checklist.

Thirty-three species of Chalcidoidea (Hymenoptera) are newly recorded from the Maltese Islands, of which, 19 include host data. An updated checklist for the 181 chalcidoid species recorded from Malta is also included, which belong to 17 families as follows: Agaonidae (3), Aphelinidae (21, 1 as new record), Azotidae (1), Chalcididae (8 species, 5 as new records), Encyrtidae (24, 1 as new record), Eulophidae (51, 16 are new records), Eupelmidae (9, 2 as new records), Eurytomidae (6, 1 as new record), Leucospidae (4), Megastigmidae (1), Mymaridae (2), Ormyridae (1), Perilampidae (1 new record), Pteromalidae (39, 5 as new records), Signiphoridae (2), Tetracampidae (1) and Torymidae (7, 1 as new record).

First Maltese record of Stephanopachys quadricollis (Marseul, 1879) (Coleoptera, Bostrichidae).

Three specimens of Stephanopachys quadricollis (Marseul, 1878) were recently found in Malta in UV light traps and represent the first record of this species for this country. Although Stephanopachys quadricollis is native to the Mediterranean basin, it is not yet clear if these Maltese records are due to a natural population or to an interception. Distributional, nomenclatural and biological data on this species are summarized, and a new synonymy is established: Stephanopachys quadricollis (Marseul, 1879) = Stephanopachys quadraticollis Kocher, 1956, syn. n.

Psocids from Malta (Insecta: Psocodea: 'Psocoptera'), with new synonymy for Peripsocus stagnivagus based on the discovery of its first Palaearctic male.

About 2,000 specimens of Psocoptera were collected in Malta recently. Examination of this material revealed 21 new records for the Maltese archipelago, augmenting the known psocid fauna of these islands from 6 to 27 species. One of the most abundant species is Peripsocus stagnivagus Chapman, 1930 (= P. bivari Baz, 1988 = P. leleupi Badonnel, 1976, new synonymies), formerly considered to be a predominantly Nearctic species. The discovery in Malta, of one male of this usually parthenogenetic species enabled comparison of this first Palaearctic male with the well-documented, rare Nearctic male. The lack of any morphological difference between these males, or between females from the Nearctic, the western Palaearctic and several Atlantic islands, supports the proposed synonymies.