Safe and valid? A systematic review of the psychometric properties of culturally adapted depression scales for use among Indigenous populations.

Background: Implementing culturally sensitive psychometric measures of depression may be an effective strategy to improve acceptance, response rate, and reliability of psychological assessment among Indigenous populations. However, the psychometric properties of depression scales after cultural adaptation remain unclear. Methods: We screened the Ovid Medline, PubMed, Embase, Global Health, PsycInfo, and CINAHL databases through three levels of search terms: Depression, Psychometrics, and Indigenous, following the PRISMA guidelines. We assessed metrics for reliability (including Cronbach's alpha), validity (including fit indices), and clinical utility (including predictive value). Results: Across 31 studies included the review, 13 different depression scales were adapted through language or content modification. Sample populations included Indigenous from the Americas, Asia, Africa, and Oceania. Most cultural adaptations had strong psychometric properties; however, few and inconsistent properties were reported. Where available, alphas, inter-rater and test-retest reliability, construct validity, and incremental validity often indicated increased cultural sensitivity of adapted scales. There were mixed results for clinical utility, criterion validity, cross-cultural validity, sensitivity, specificity, area under the receiver operating characteristic curve, predictive value, and likelihood ratio. Conclusions: Modifications to increase cultural relevance have the potential to improve fit and acceptance of a scale by the Indigenous population, however, these changes may decrease specificity and negative predictive value. There is an urgent need for suitable tools that are useful and reliable for identifying Indigenous individuals for clinical treatment of depression. This awaits future work for optimal specificity and validated cut-off points that take into account the high prevalence of depression in these populations.

The evolution of intramitochondriality in Midichloria bacteria.

Midichloria spp. are intracellular bacterial symbionts of ticks. Representatives of this genus colonise mitochondria in the cells of their hosts. To shed light on this unique interaction we evaluated the presence of an intramitochondrial localization for three Midichloria in the respective tick host species and generated eight high-quality draft genomes and one closed genome, showing that this trait is non-monophyletic, either due to losses or multiple acquisitions. Comparative genomics supports the first hypothesis, as the genomes of non-mitochondrial symbionts are reduced subsets of those capable of colonising the organelles. We detect genomic signatures of mitochondrial tropism, including the differential presence of type IV secretion system and flagellum, which could allow the secretion of unique effectors and/or direct interaction with mitochondria. Other genes, including adhesion molecules, proteins involved in actin polymerisation, cell wall and outer membrane proteins, are only present in mitochondrial symbionts. The bacteria could use these to manipulate host structures, including mitochondrial membranes, to fuse with the organelles or manipulate the mitochondrial network.

The methods of improving cultural sensitivity of depression scales for use among global indigenous populations: a systematic scoping review.

Cultural adaptation of psychometric measures has become a process aimed at increasing acceptance, reliability, and validity among specific Indigenous populations. We present a systematic scoping review to: (1) identify the depression scales that have been culturally adapted for use among Indigenous populations worldwide, (2) globally report on the methods used in the cultural adaptation of those scales, and (3) describe the main features of those cultural adaptation methods. We included articles published from inception to April 2021, including 3 levels of search terms: Psychometrics, Indigenous, and Depression. The search was carried out in the Ovid Medline, PubMed, Embase, Global Health, PsycINFO, and CINAHL databases, following PRISMA guidelines. We identified 34 reports on processes of cultural adaptation that met the criteria. The scales were adapted for use among Indigenous populations from Africa, Australia, Asia, North America, and Latin America. The most common scales that underwent adaptation were the Patient Health Questionnaire (PHQ-9), the Center for Epidemiologic Studies Depression Scale (CES-D), and the Edinburgh Postnatal Depression Scale (EPDS). Methods of adaptation involved a revision of the measures' cultural appropriateness, standard/transcultural translation, revision of the administration process, and inclusion of visual supports. Culturally safe administration of scales was reported in some studies. To come to a consensus on most appropriate methods of improving cultural safety of psychometric measurement, most studies utilized qualitative methods or mixed methods to understand the specific community's needs. Revision of linguistic equivalence and cultural relevance of content, culturally safe administration procedures, qualitative methods, and participatory research were key features of developing safe culturally adapted measures for depressive symptoms among Indigenous populations. While for comparability, uniform scales would be ideal as mental health evaluations, an understanding of the cultural impact of measurements and local depression expressions would benefit the process of developing culturally sensitive psychometric scales. PROSPERO registration ID: CRD42023391439.

Individualized Intervention to Support Mental Health Recovery Through Implementation of Digital Tools into Clinical Care: Feasibility Study.

Myriad digital tools exist to support mental health but there are multiple barriers to using these tools in routine care. This study aimed to assess the feasibility of an intervention incorporating a support role to help the clinical team identify and use technology to promote recovery. The technology specialist intervention is 3 months in duration and comprises four stages: goal setting, researching and evaluating tools, demonstrating and selecting tools, and ongoing support. We implemented the intervention in a community mental health center and a dual diagnosis treatment program, working with eight clients and their case managers. Clients and case managers willingly engaged with the technology specialist and found the intervention beneficial. Integration and collaboration with the care team facilitated implementation of the technology specialist in these real-world settings. Clients reported that the intervention made it easy to try a digital tool. Six of the eight participants stated that they made substantial progress toward their goals. The technology specialist is a promising new role for mental health care delivery to augment traditional services and enhance individualized recovery.

Demographic and Clinical Presentations of Youth using Enhanced Mental Health Services in Six Indigenous Communities from the ACCESS Open Minds Network.

OBJECTIVE: In many Indigenous communities, youth mental health services are inadequate. Six Indigenous communities participating in the ACCESS Open Minds (AOM) network implemented strategies to transform their youth mental health services. This report documents the demographic and clinical presentations of youth accessing AOM services at these Indigenous sites. METHODS: Four First Nations and two Inuit communities contributed to this study. Youth presenting for mental health services responded to a customized sociodemographic questionnaire and presenting concerns checklist, and scales assessing distress, self-rated health and mental health, and suicidal thoughts and behaviors. RESULTS: Combined data from the First Nations sites indicated that youth across the range of 11-29 years accessed services. More girls/women than boys/men accessed services; 17% identified as LBGTQ+. Most (83%) youth indicated having access to at least one reliable adult and getting along well with the people living with them. Twenty-five percent of youth reported difficulty meeting basic expenses. Kessler (K10) distress scores indicated that half likely had a moderate mental health problem and a fourth had severe problems. Fifty-five percent of youth rated their mental health as fair or poor, while 50% reported suicidal thoughts in the last month. Anxiety, stress, depression and sleep issues were the most common presenting problems. Fifty-one percent of youth either accessed services themselves or were referred by family members. AOM was the first mental health service accessed that year for 68% of youth. CONCLUSIONS: This report is the first to present a demographic and clinical portrait of youth presenting at mental health services in multiple Indigenous settings in Canada. It illustrates the acceptability and feasibility of transforming youth mental health services using core principles tailored to meet communities' unique needs, resources, and cultures, and evaluating these using a common protocol. Data obtained can be valuable in evaluating services and guiding future service design. Trial registration name and number at Clinicaltrials.gov: ACCESS Open Minds/ACCESS Esprits ouverts, ISRCTN23349893.

Tools and tutorial on practical ray tracing for microscopy.

Significance: An advanced understanding of optical design is necessary to create optimal systems but this is rarely taught as part of general curriculum. Compounded by the fact that professional optical design software tools have a prohibitive learning curve, this means that neither knowledge nor tools are easily accessible. Aim: In this tutorial, we introduce a raytracing module for Python, originally developed for teaching optics with ray matrices, to simplify the design and optimization of optical systems. Approach: This module is developed for ray matrix calculations in Python. Many important concepts of optical design that are often poorly understood such as apertures, aperture stops, and field stops are illustrated. Results: The module is explained with examples in real systems with collection efficiency, vignetting, and intensity profiles. Also, the optical invariant, an important benchmark property for optical systems, is used to characterize an optical system. Conclusions: This raytracing Python module will help improve the reader's understanding of optics and also help them design optimal systems.

Reliability and Feasibility of the First-Episode Psychosis Services Fidelity Scale-Revised for Remote Assessment.

OBJECTIVE: The authors sought to evaluate the interrater reliability and feasibility of the First-Episode Psychosis Services Fidelity Scale-Revised (FEPS-FS-R) for remote assessment of first-episode psychosis programs according to the coordinated specialty care model. METHODS: The authors used the FEPS-FS-R to assess the fidelity of 36 first-episode psychosis program sites in the United States with information from three sources: administrative data, health record review, and phone interviews with staff. Four raters independently conducted fidelity assessments of five program sites by listening to each of the staff interviews and independently rating the two other data sources from each site. To calculate interrater reliability, the authors used intraclass correlation coefficients (ICCs) for each of the five sites and across the total scores for each site. RESULTS: Total interrater reliability was in the good to excellent range, with a mean ICC of 0.91 (95% confidence interval = 0.72-0.99, p<0.001). Two first-episode psychosis program sites (6%) achieved excellent fidelity, 25 (69%) good fidelity, and nine (25%) fair fidelity. Of the 32 distinct items on the FEPS-FS-R, 23 (72%) were used with good or excellent fidelity. Most sites achieved high fidelity on most items, but five items received ratings indicating low-fidelity use at most sites. The fidelity assessment proved feasible, and sites required on average 10.5 hours for preparing and conducting the fidelity review. CONCLUSIONS: The FEPS-FS-R has high interrater reliability and can differentiate high-, moderate-, and low-fidelity sites. Most sites had good overall fidelity, but the FEPS-FS-R identified some services that were challenging to implement at many sites.

A novel Borrelia species, intermediate between Lyme disease and relapsing fever groups, in neotropical passerine-associated ticks.

Lyme disease (LD) and relapsing fevers (RF) are vector-borne diseases caused by bacteria of the Borrelia genus. Here, we report on the widespread infection by a non-described Borrelia species in passerine-associated ticks in tropical rainforests of French Guiana, South America. This novel Borrelia species is common in two tick species, Amblyomma longirostre and A. geayi, which feed on a broad variety of neotropical mammal and bird species, including migratory species moving to North America. The novel Borrelia species is divergent from the LD and RF species, and is more closely related to the reptile- and echidna-associated Borrelia group that was recently described. Genome sequencing showed that this novel Borrelia sp. has a relatively small genome consisting of a 0.9-Mb-large chromosome and an additional 0.3 Mb dispersed on plasmids. It harbors an RF-like genomic organization but with a unique mixture of LD- and RF-specific genes, including genes used by RF Borrelia for the multiphasic antigen-switching system and a number of immune-reactive protein genes used for the diagnosis of LD. Overall, our data indicate that this novel Borrelia is an intermediate taxon between the LD and RF species that may impact a large host spectrum, including American mammals. The designation "Candidatus Borrelia mahuryensis" is proposed for this species.

Distribution of ticks, tick-borne pathogens and the associated local environmental factors including small mammals and livestock, in two French agricultural sites: the OSCAR database.

BACKGROUND: In Europe, ticks are major vectors of both human and livestock pathogens (e.g. Lyme disease, granulocytic anaplasmosis, bovine babesiosis). Agricultural landscapes, where animal breeding is a major activity, constitute a mosaic of habitat types of various quality for tick survival and are used at different frequencies by wild and domestic hosts across seasons. This habitat heterogeneity, in time and space, conditions the dynamics of these host-vector-pathogen systems and thus drives acarological risk (defined as the density of infected ticks). The principal objective of the OSCAR project (2011-2016) was to examine the links between this heterogeneity and acarological risk for humans and their domestic animals. Here, we present the data associated with this project. NEW INFORMATION: This paper reports a database on the distribution and densities of I. ricinus ticks - the most common tick species in French agricultural landscapes - and the prevalence of three tick-borne pathogens (Anaplasma phagocytophilum, Borrelia spp. and Babesia spp.) in two sites in north-western ("Zone Atelier Armorique": ZA site) and south-western ("Vallées et Coteaux de Gascogne": VG site) France. The distribution and density of ticks along a gradient of wooded habitats, as well as biotic variables, such as the presence and abundance of their principal domestic (livestock) and wild hosts (small mammals), were measured from forest cores and edges to more or less isolated hedges, all bordering meadows. Ticks, small mammals and information on local environmental conditions were collected along 90 transects in each of the two sites in spring and autumn 2012 and 2013 and in spring 2014, corresponding to the main periods of tick activity. Local environmental conditions were recorded along each tick and small mammal transect: habitat type, vegetation type and characteristics, slope and traces of livestock presence. Samples consisted of questing ticks collected on the vegetation (mainly I. ricinus nymphs), biopsies of captured small mammals and ticks fixed on small mammals. In the VG site, livestock occurrence and abundance were recorded each week along each tick transect.A total of 29004 questing ticks and 1230 small mammals were captured during the study across the two sites and over the five field campaigns. All questing nymphs (N = 12287) and questing adults (N = 646) were identified to species. Ticks from small mammals (N = 1359) were also identified to life stage. Questing nymphs (N = 4518 I. ricinus) and trapped small mammals (N = 908) were analysed for three pathogenic agents: A. phagocytophilum, Borrelia spp. and Babesia spp.In the VG site, the average prevalence in I. ricinus nymphs for A. phagocytophilum, Borrelia spp. and Babesia spp. were, respectively 1.9% [95% CI: 1.2-2.5], 2.5% [95% CI: 1.8-3.2] and 2.7% [95% CI: 2.0-3.4]. In small mammals, no A. phagocytophilum was detected, but the prevalence for Borrelia spp. was 4.2% [95% CI: 0.9-7.5]. On this site, there was no screening of small mammals for Babesia spp. In ZA site, the average prevalence in nymphs for A. phagocytophilum, Borrelia spp. and Babesia were, respectively 2.2% [95% CI: 1.6-2.7], 3.0% [95% CI: 2.3-3.6] and 3.1% [95% CI: 2.5-3.8]. In small mammals, the prevalence of A. phagocytophilum and Borrelia spp. were, respectively 6.9% [95% CI: 4.9-8.9] and 4.1% [95% CI: 2.7-5.9]. A single animal was found positive for Babesia microti at this site amongst the 597 tested.

Next-Generation Sequencing on Insectivorous Bat Guano: An Accurate Tool to Identify Arthropod Viruses of Potential Agricultural Concern.

Viruses belonging to the Dicistroviridae family have attracted a great deal of attention from scientists owing to their negative impact on agricultural economics, as well as their recent identification as potential aetiological agents of febrile illness in human patients. On the other hand, some Dicistroviruses are also studied for their potential biopesticide properties. To date, Dicistrovirus characterized in African mainland remain scarce. By using High-Throughput Sequencing technology on insectivorous bat faeces (Hipposideros Caffer) sampled in a cave used by humans to collect bat guano (bat manure) as fertilizer in Zimbabwe, we characterized the full-length sequences of three Dicistrovirus belonging to the Cripavirus and Aparavirus genus: Big Sioux River Virus-Like (BSRV-Like), Acute Bee Paralysis Virus (ABPV), and Aphid Lethal Paralysis Virus (ALPV). Phylogenetic analyses of ORF-1 and ORF-2 genes showed a complex evolutionary history between BSRV and close viruses, as well as for the Aparavirus genus. Herewith, we provide the first evidence of the presence of Dicistrovirus in Zimbabwe and highlight the need to further document the impact of such viruses on crops, as well as in beekeeping activities in Zimbabwe which represent a crucial source of income for Zimbabwean people.

The technology specialist: a 21st century support role in clinical care.

Mental health clinicians, clients, and researchers have shown keen interest in using technology to support mental health recovery. However, technology has not been routinely integrated into clinical care. Clients use a wide range of digital tools and apps to help manage their mental health, but clinicians rarely discuss this form of self-management in clinical interactions. This absence of communication is concerning because the safety and quality of the digital tools and apps people use may negatively affect their mental health outcomes. Mental health systems could benefit from someone to help identify technology-based supports that reflect current evidence and minimize privacy and security concerns. This technology specialist may also enhance the therapeutic bond between the client and the clinician. In working with a technology specialist, clients may begin to gain a sense of control over their mental health, and perhaps use fewer mental health services.

Use of Mobile and Computer Devices to Support Recovery in People With Serious Mental Illness: Survey Study.

BACKGROUND: Mental health recovery refers to an individual's experience of gaining a sense of personal control, striving towards one's life goals, and meeting one's needs. Although people with serious mental illness own and use electronic devices for general purposes, knowledge of their current use and interest in future use for supporting mental health recovery remains limited. OBJECTIVE: This study aimed to identify smartphone, tablet, and computer apps that mental health service recipients use and want to use to support their recovery. METHODS: In this pilot study, we surveyed a convenience sample of 63 mental health service recipients with serious mental illness. The survey assessed current use and interest in mobile and computer devices to support recovery. RESULTS: Listening to music (60%), accessing the internet (59%), calling (59%), and texting (54%) people were the top functions currently used by participants on their device to support their recovery. Participants expressed interest in learning how to use apps for anxiety/stress management (45%), mood management (45%), monitoring mental health symptoms (43%), cognitive behavioral therapy (40%), sleep (38%), and dialectical behavior therapy (38%) to support their recovery. CONCLUSIONS: Mental health service recipients currently use general functions such as listening to music and calling friends to support recovery. Nevertheless, they reported interest in trying more specific illness-management apps.

Real-World Technology Use Among People With Mental Illnesses: Qualitative Study.

BACKGROUND: There is growing interest in using technology-based tools to support mental health recovery. Yet, despite evidence suggesting widespread access to technology among people with mental illnesses, interest in using technology to support mental health, and effectiveness of technology-based tools developed by researchers, such tools have not been widely adopted within mental health settings. Little is currently known about how mental health consumers are using technology to address mental health needs in real-world settings outside of controlled research studies. OBJECTIVE: This qualitative study examined current practices and orientations toward technology among consumers in 3 mental health settings in the United States. METHODS: Ethnographic observations and semistructured interviews were conducted. Observations focused on if and how technology was salient within the setting and documented relevant behaviors, interactions, and dialogue in fieldnotes. Ethnographic data informed the development of a semistructured interview that inquired into technology use and interest among consumers (n=15) in a community mental health setting. Fieldnotes and interview transcripts were reviewed and coded by multiple researchers. Key concepts and patterns identified were refined by the research team to develop the main findings. RESULTS: Ownership of technology, although common, was not ubiquitous and was varied across the sites. Participants had varying levels of awareness regarding the key capabilities of modern technologies. Participants used technology for many purposes, but there was limited evidence of technology use to support mental health. Technology-based tools specific to mental health were not routinely used, although some participants found widely available mobile apps to be helpful in recovery. CONCLUSIONS: Qualitative findings suggest that many, but not all, clients will be interested in using technology to support mental health needs. The variability in type and quality of technology owned by participants suggests the need to design for a range of functionality in the development of mental health tools. Findings also suggest thinking broadly about using existing platforms and widely available tools to support consumers in mental health recovery.

Tick-Bacteria Mutualism Depends on B Vitamin Synthesis Pathways.

Mutualistic interactions with microbes have facilitated the radiation of major eukaryotic lineages [1, 2]. Microbes can notably provide biochemical abilities, allowing eukaryotes to adapt to novel habitats or to specialize on particular feeding niches [2-4]. To investigate the importance of mutualisms for the exclusive blood feeding habits of ticks, we focused on a bacterial genus of medical interest, Francisella, which is known to include both virulent intracellular pathogens of vertebrates [5, 6] and maternally inherited symbionts of ticks [7-9]. Through a series of physiological experiments, we identified a Francisella type, F-Om, as an obligate nutritional mutualist in the life cycle of the African soft tick Ornithodoros moubata. Francisella F-Om mutualism synthesizes B vitamins that are deficient in the blood meal of ticks. Indeed, experimental elimination of Francisella F-Om resulted in alteration of tick life history traits and physical abnormalities, deficiencies which were fully restored with an oral supplement of B vitamins. We also show that Francisella F-Om is maternally transmitted to all maturing tick oocytes, suggesting that this heritable symbiont is an essential adaptive element in the life cycle of O. moubata. The Francisella F-Om genome further revealed a recent origin from a Francisella pathogenic life style, as observed in other Francisella symbionts [6, 7, 10]. Though half of its protein-coding sequences are now pseudogenized or lost, Francisella F-Om has kept several B vitamin synthesis pathways intact, confirming the importance of these genes in evolution of its nutritional mutualism with ticks.

An Adapted Measure of Sibling Attachment: Factor Structure and Internal Consistency of the Sibling Attachment Inventory in Youth.

Parent-youth and peer relationship inventories based on attachment theory measure communication, trust, and alienation, yet sibling relationships have been overlooked. We developed the Sibling Attachment Inventory and evaluated its psychometric properties in a sample of 172 youth ages 10-14 years. We adapted the 25-item Sibling Attachment Inventory from the Inventory of Parent and Peer Attachment-Revised peer measure. Items loaded onto three factors, identified as communication, trust, and alienation, α = 0.93, 0.90, and 0.76, respectively. Sibling trust and alienation correlated with depression (r s = -0.33, r s = 0.48) and self-worth (r s = 0.23; r s = -0.32); sibling trust and alienation correlated with depression after controlling for parent trust and parent alienation (r s = -0.23, r s = 0.22). Preliminary analyses showed good internal consistency, construct validity, and incremental predictive validity. Following replication of these properties, this measure can facilitate large cohort assessments of sibling attachment.

Evolutionary changes in symbiont community structure in ticks.

Ecological specialization to restricted diet niches is driven by obligate, and often maternally inherited, symbionts in many arthropod lineages. These heritable symbionts typically form evolutionarily stable associations with arthropods that can last for millions of years. Ticks were recently found to harbour such an obligate symbiont, Coxiella-LE, that synthesizes B vitamins and cofactors not obtained in sufficient quantities from blood diet. In this study, the examination of 81 tick species shows that some Coxiella-LE symbioses are evolutionarily stable with an ancient acquisition followed by codiversification as observed in ticks belonging to the Rhipicephalus genus. However, many other Coxiella-LE symbioses are characterized by low evolutionary stability with frequent host shifts and extinction events. Further examination revealed the presence of nine other genera of maternally inherited bacteria in ticks. Although these nine symbionts were primarily thought to be facultative, their distribution among tick species rather suggests that at least four may have independently replaced Coxiella-LE and likely represent alternative obligate symbionts. Phylogenetic evidence otherwise indicates that cocladogenesis is globally rare in these symbioses as most originate via horizontal transfer of an existing symbiont between unrelated tick species. As a result, the structure of these symbiont communities is not fixed and stable across the tick phylogeny. Most importantly, the symbiont communities commonly reach high levels of diversity with up to six unrelated maternally inherited bacteria coexisting within host species. We further conjecture that interactions among coexisting symbionts are pivotal drivers of community structure both among and within tick species.

Barriers to Employment for Transition-age Youth with Developmental and Psychiatric Disabilities.

Youth with developmental and psychiatric disabilities encounter significant vocational challenges, even when they receive supported employment services. We examined the barriers to employment for 280 transition-age youth with disabilities enrolled in supported employment in eight community rehabilitation centers. Employment team members identified each youth's top three barriers to employment using a 21-item checklist. Lack of work experience, transportation problems, and program engagement issues represented common barriers for both youth with developmental disabilities (53, 36, and 25%) and youth with psychiatric disabilities (20, 33, and 26%). Additional common barriers among youth with developmental disabilities included cognitive problems (32%) and lack of social skills (23%) and among youth with psychiatric disabilities included poor control of psychiatric symptoms (23%). Despite receiving evidence-based employment services, youth with disabilities encounter many barriers to employment. Awareness of typical barriers for transition-age youth, including those specific to different disability groups, may help employment programs anticipate challenges and develop strategies that avoid these barriers and their effects on employment opportunities.

Barriers and Facilitators to Sustainment of an Evidence-Based Supported Employment Program.

Large-scale initiatives to expand evidence-based practices are often poorly implemented and rarely endure. The purpose of this study was to identify the perceived barriers and facilitators to sustainment of an evidence-based supported employment program, Individual Placement and Support (IPS). Within a 2-year prospective study of sustainment among 129 IPS programs in 13 states participating in a national learning community, we interviewed IPS team leaders and coded their responses to semi-structured interviews using a conceptual framework adapted from another large-scale implementation study. Leaders in 122 agencies (95%) that sustained their IPS programs identified funding, prioritization, and workforce characteristics as both key facilitators and barriers. Additional key factors were lack of local community supports as a barrier and leadership and structured workflow as facilitators. Within the IPS learning community, team leaders attributed the sustainment of their program to funding, prioritization, workforce, agency leadership, and structured workflow. The actions of the learning community's leadership, state governments, and local programs together may have contributed to the high sustainment rate.

Linking morphometric and genetic divergence with host use in the tick complex, Ornithodoros capensis sensu lato.

Host specific adaptations in parasites can lead to the divergence of conspecific populations. However, this divergence can be difficult to measure because morphological changes may not be expressed or because obvious changes may simply reflect phenotypic plasticity. Combining both genetic and phenotypic information can enable a better understanding of the divergence process and help identify the underlying selective forces, particularly in closely-related species groups. Here, we link genetic and morphometric data to understand divergence patterns within the Ornithodoros (Carios) capensis complex, a group of soft ticks (Argasidae) exploiting colonial seabirds across the globe. Species designations in this complex were historically based on larval morphology and geographic location. However, recent work has suggested that divergence within the group may be at least partially linked to host specificity. We therefore first examined population genetic structure of ticks in relation to host use and geography. These analyses revealed strong structure in relation to host use, both when populations were sympatric and widely allopatric, with a secondary effect of geography. They also demonstrated the presence of several novel and presumably undescribed species exploiting these seabird hosts. We then used geometric morphometrics (landmark and outline analyses) to test whether host-associated genetic divergence is always accompanied by the same phenotypic changes. We found that morphological variation (size and shape) correlated well with genetic structure; tick size and shape varied strongly in relation to host type, and weakly with geography. These results support the hypothesis that speciation in this tick group has been more strongly shaped by host use than by geographic barriers per se. The revealed phenetic patterns now require detailed investigation to link them with host-specific selective forces.

A wide diversity of Pantoea lineages are engaged in mutualistic symbiosis and cospeciation processes with stinkbugs.

Pantoea are emerging as widespread bacteria engaged in associations with a variety of hosts, including plants, insects and humans. Recently, mutualistic Pantoea gut symbionts have also been reported in pentatomid stinkbugs. In the present study, we examine the incidence and evolutionary history of these Pantoea symbionts in pentatomid stinkbug populations from 14 species, characterising the processes that shape their diversity. We identify midgut crypts of pentatomid stinkbugs as harboring a remarkable diversity of Pantoea. Present in 10 of the 14 sampled host species, multi-locus typing revealed the presence of 10 novel Panteoa lineages, all highly differentiated from the known Panteoa species. Rearing experiments of two pentatomid stinkbug species confirmed that these novel Panteoa are maternally inherited through egg smearing and engaged in mutualistic interactions with their hosts. Phylogenetic investigations further revealed that the Pantoea evolutionary history in pentatomid stinkbugs was notably complex: it has been shaped not only by horizontal transfers with frequent host turnover but also by strict vertical transmission over long evolutionary periods, resulting in host-symbiont codiversification.