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Racialized, deficit-oriented educational practices and inadequate safe spaces for youth undermine Communities of Color. We discuss our after-school program's framework, strategies, activities, and partnerships with community stakeholders, demonstrating that a collaborative, culturally responsive, strengths-based approach to mitigate trauma and enhance health and educational opportunities is essential for empowering Chicana/o/Latina/o youth and families.
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Hispánicos o Latinos , Humanos , Adolescente , Femenino , Masculino , Niño , Instituciones Académicas , Guyana/etnologíaRESUMEN
Severe Lonomia caterpillar envenoming is an increasing hazard in South America. It can trigger severe coagulation disorders that can progress to systemic complications and death. We report the first documented case of severe Lonomia caterpillar envenoming in Guyana. It was managed using antivenom provided by the Brazilian Ministry of Health as part of humanitarian support. This case describes a successful international collaboration driving a favorable outcome for the envenomed patient.
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Antivenenos , Animales , Humanos , Antivenenos/uso terapéutico , Guyana , Cooperación Internacional , Masculino , Mordeduras y Picaduras de Insectos , Mariposas Nocturnas , Venenos de Artrópodos , Adulto , BrasilRESUMEN
Countries within the tropics face ongoing challenges in completing or updating their national forest inventories (NFIs), critical for estimating aboveground biomass (AGB) and for forest-related greenhouse gas (GHG) accounting. While previous studies have explored the integration of map information with local reference data to fill in data gaps, limited attention has been given to the specific challenges presented by the clustered plot designs frequently employed by NFIs when combined with remote sensing-based biomass map units. This research addresses these complexities by conducting four country case-studies, encompassing a variety of NFI characteristics within a range of AGB densities. Examining four country case-studies (Peru, Guyana, Tanzania, Mozambique), we assess the potential of European Space Agency's Climate Change Initiative (CCI) global biomass maps to increase precision in (sub)national AGB estimates. We compare a baseline approach using NFI field-based data with a model-assisted scenario incorporating a locally calibrated CCI biomass map as auxiliary information. The original CCI biomass maps systematically underestimate AGB in three of the four countries at both the country and stratum level, with particularly weak agreement at finer map resolution. However, after calibration with country-specific NFI data, stratum and country-level AGB estimates from the model-assisted scenario align well with those obtained solely from field-based data and official country reports. Introducing maps as a source of auxiliary information fairly increased the precision of stratum and country-wise AGB estimates, offering greater confidence in estimating AGB for GHG reporting purposes. Considering the challenges tropical countries face with implementing their NFIs, it is sensible to explore the potential benefits of biomass maps for climate change reporting mechanisms across biomes. While country-specific NFI design assumptions guided our model-assisted inference strategies, this study also uncovers transferable insights from the application of global biomass maps with NFI data, providing valuable lessons for climate research and policy communities.
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Biomasa , Cambio Climático , Monitoreo del Ambiente , Monitoreo del Ambiente/métodos , Bosques , Tanzanía , Clima Tropical , Mozambique , Guyana , Gases de Efecto Invernadero/análisisRESUMEN
Fish stocks have declined rapidly over the past half-century due to the increased demand for seafood and unsustainable fishing practices. The incidental capture of non-target species (bycatch) is a pervasive issue in fisheries management and has led to population declines in non-target species worldwide. The fisheries sector in Guyana currently supports the livelihoods of over 10,000 Guyanese and contributes approximately 2% to the country's GDP. Bycatch is believed to be a major threat to Guyana's marine fisheries, especially the small-scale sector, due to a lack of management infrastructure and limited data and monitoring. Here, we assessed bycatch in Guyana's artisanal gillnet and Chinese seine fisheries through vessel observations and semi-structured interviews with local fishers. Most of the discarded species documented had no commercial importance to the fisheries in Guyana. Although no statistical difference was observed among the bycatch rates in the gillnet and Chinese seine fisheries, the latter generally had more discarded individuals, most of which were juveniles. The Shannon-Weiner diversity index showed a greater diversity of bycatch species in the gillnet fisheries compared to the Chinese seine. Jaccard's similarity index indicated a low similarity among the gear types. Even though most fishers were aware of bycatch, they did not view it as a major issue and were not interested in reducing their discards. We recommend a collaborative approach in exploring solutions to ensure the ecological and socioeconomic sustainability of the fisheries sector.
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Conservación de los Recursos Naturales , Explotaciones Pesqueras , Guyana , Animales , Conservación de los Recursos Naturales/métodos , Peces , Biodiversidad , Alimentos MarinosRESUMEN
Plasmodium parasites, the causal agents of malaria, are eukaryotic organisms that obligately undergo sexual recombination within mosquitoes. In low transmission settings, parasites recombine with themselves, and the clonal lineage is propagated rather than broken up by outcrossing. We investigated whether stochastic/neutral factors drive the persistence and abundance of Plasmodium falciparum clonal lineages in Guyana, a country with relatively low malaria transmission, but the only setting in the Americas in which an important artemisinin resistance mutation (pfk13 C580Y) has been observed. We performed whole genome sequencing on 1,727 Plasmodium falciparum samples collected from infected patients across a five-year period (2016-2021). We characterized the relatedness between each pair of monoclonal infections (n = 1,409) through estimation of identity-by-descent (IBD) and also typed each sample for known or candidate drug resistance mutations. A total of 160 multi-isolate clones (mean IBD ≥ 0.90) were circulating in Guyana during the study period, comprising 13 highly related clusters (mean IBD ≥ 0.40). In the five-year study period, we observed a decrease in frequency of a mutation associated with artemisinin partner drug (piperaquine) resistance (pfcrt C350R) and limited co-occurence of pfcrt C350R with duplications of plasmepsin 2/3, an epistatic interaction associated with piperaquine resistance. We additionally observed 61 nonsynonymous substitutions that increased markedly in frequency over the study period as well as a novel pfk13 mutation (G718S). However, P. falciparum clonal dynamics in Guyana appear to be largely driven by stochastic factors, in contrast to other geographic regions, given that clones carrying drug resistance polymorphisms do not demonstrate enhanced persistence or higher abundance than clones carrying polymorphisms of comparable frequency that are unrelated to resistance. The use of multiple artemisinin combination therapies in Guyana may have contributed to the disappearance of the pfk13 C580Y mutation.
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Antimaláricos , Resistencia a Medicamentos , Malaria Falciparum , Plasmodium falciparum , Plasmodium falciparum/genética , Plasmodium falciparum/efectos de los fármacos , Guyana , Malaria Falciparum/parasitología , Malaria Falciparum/epidemiología , Malaria Falciparum/tratamiento farmacológico , Humanos , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Resistencia a Medicamentos/genética , Artemisininas/farmacología , Artemisininas/uso terapéutico , Mutación , Proteínas Protozoarias/genéticaRESUMEN
BACKGROUND: To assess the attitudes of women towards intimate partner violence (IPV) in Guyana. METHODS: We used national data from the publicly available Multiple Indicator Cluster Survey (MICS) conducted in Guyana in 2019 for women aged 15 to 49 years. The prevalence of women who agreed that a husband is justified in beating his wife was analyzed. Respondent reasons included if she: "goes out without telling him", "neglects the children", "argues with him", "refuses sex with him", "burns the food", "has another partner", "stays out late/partying", "refuses to cook or clean", "overspends", and/or "he doesn't have access to her cellphone". Descriptive analyses were carried for all the variables. Logistic regression was used to identify factors associated with these 10 respondent reasons, separately and in combination. RESULTS: The overall prevalence of women's attitudes justifying IPV against women if there was a 'yes' response to any of the 10 reasons was 17.9% (95%CI: 16.6-19.3%), and varied from 2.7% if she "goes out without telling him", "burns the food", or "overspends" to 10.0% if she "has another partner". This prevalence ranged from 10.2% in urban areas to 19.3% in rural areas (p<0.001), and from 16.1% in coastal to 30.1% in interior areas (p<0.001). Similarly, 25.9% of women from the poorest household agreed that a husband has the right in beating his wife for any of the 10 reasons compared to 11.6% of the richest women (11.6%) (p<0.001). Rural place of residence, ethnicity, geographic region, level of education, wealth quintile, ever used of a computer, and frequency of listening to the radio were significant factors associated with women's attitudes justifying IPV against women (p<0.05). CONCLUSION: Over one-sixth of the respondents agreed that a husband was justified in committing IPV against women in Guyana. Public health programs focusing on geographic locations, ethnicity, and economic status must be implemented to change attitudes justifying IPV and reduce this significant public health challenge.
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Violencia de Pareja , Humanos , Femenino , Adulto , Estudios Transversales , Violencia de Pareja/psicología , Violencia de Pareja/estadística & datos numéricos , Adolescente , Persona de Mediana Edad , Adulto Joven , Guyana/epidemiología , Masculino , Prevalencia , Actitud , Encuestas y Cuestionarios , Población RuralRESUMEN
The consumption of primates is integral to the traditional subsistence strategies of many Indigenous communities throughout Amazonia. Understanding the overall health of primates harvested for food in the region is critical to Indigenous food security and thus, these communities are highly invested in long-term primate population health. Here, we describe the establishment of a surveillance comanagement program among the Waiwai, an Indigenous community in the Konashen Amerindian Protected Area (KAPA). To assess primate health in the KAPA, hunters performed field necropsies on primates harvested for food and tissues collected from these individuals were analyzed using histopathology. From 2015 to 2019, hunters conducted 127 necropsies across seven species of primates. Of this sample, 82 primates (between 2015 and 2017) were submitted for histopathological screening. Our histopathology data revealed that KAPA primates had little evidence of underlying disease. Of the tissue abnormalities observed, the majority were either due to diet (e.g., hepatocellular pigment), degenerative changes resulting from aging (e.g., interstitial nephritis, myocyte lipofusion), or nonspecific responses to antigenic stimulation (renal and splenic lymphoid hyperplasia). In our sample, 7.32% of individuals had abnormalities that were consistent with a viral etiology, including myocarditis and hepatitis. Internal parasites were observed in 53.66% of individuals and is consistent with what would be expected from a free-ranging primate population. This study represents the importance of baseline data for long-term monitoring of primate populations hunted for food. More broadly, this research begins to close a critical gap in zoonotic disease risk related to primate harvesting in Amazonia, while also demonstrating the benefits of partnering with Indigenous hunters and leveraging hunting practices in disease surveillance and primate population health assessment.
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Primates , Animales , Guyana , Humanos , Enfermedades de los Primates/virología , Masculino , Pueblos Indígenas , FemeninoRESUMEN
Mayaro virus (MAYV) is a mosquito-borne Alphavirus that is widespread in South America. MAYV infection often presents with non-specific febrile symptoms but may progress to debilitating chronic arthritis or arthralgia. Despite the pandemic threat of MAYV, its true distribution remains unknown. The objective of this study was to clarify the geographic distribution of MAYV using an established risk mapping framework. This consisted of generating evidence consensus scores for MAYV presence, modeling the potential distribution of MAYV in select countries across Central and South America, and estimating the population residing in areas suitable for MAYV transmission. We compiled a georeferenced compendium of MAYV occurrence in humans, animals, and arthropods. Based on an established evidence consensus framework, we integrated multiple information sources to assess the total evidence supporting ongoing transmission of MAYV within each country in our study region. We then developed high resolution maps of the disease's estimated distribution using a boosted regression tree approach. Models were developed using nine climatic and environmental covariates that are related to the MAYV transmission cycle. Using the output of our boosted regression tree models, we estimated the total population living in regions suitable for MAYV transmission. The evidence consensus scores revealed high or very high evidence of MAYV transmission in several countries including Brazil (especially the states of Mato Grosso and Goiás), Venezuela, Peru, Trinidad and Tobago, and French Guiana. According to the boosted regression tree models, a substantial region of South America is suitable for MAYV transmission, including north and central Brazil, French Guiana, and Suriname. Some regions (e.g., Guyana) with only moderate evidence of known transmission were identified as highly suitable for MAYV. We estimate that approximately 58.9 million people (95% CI: 21.4-100.4) in Central and South America live in areas that may be suitable for MAYV transmission, including 46.2 million people (95% CI: 17.6-68.9) in Brazil. Our results may assist in prioritizing high-risk areas for vector control, human disease surveillance and ecological studies.
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Alphavirus , Mosquitos Vectores , Animales , Humanos , Brasil , Guyana Francesa , GuyanaRESUMEN
Guyana's colonial past has left a trail of economic instability, racial polarization, and physical and mental trauma. Despite the progress made since Guyana's independence in 1966, the remnants of this colonial past continue to shape present-day Guyana. As a result, violence and trauma continue to impact the mental health of the population. This is manifest in endemic problems of domestic violence and racialized social divisions which have created the conditions for rates of suicide which are amongst the highest in the world. The formal mental health provision which exists in Guyana is based primarily on an individualized and largely biomedical model of care. Despite valuable attempts to develop this provision, the difficulty of physically accessing this for some people and the stigma which surround this means that the capacity of this system to address the serious problems which exist is limited. It is also the case that in times of emotional and psychic distress, and in the context of Guyana being a very religious country, many people turn to traditional supernatural healers and remedies for support. In this paper, we discuss what is known as "Obeah", noting that while this is widely practiced, it remains something of a taboo subject in Guyana. We consider the reasons why these practices and beliefs continue to be influential. However, what neither these biomedical or supernatural perceptions of mental health are able to address is the sociogenic nature of Guyana's mental health issues, which we argue emerges out of the historic trauma of Guyana's experience of colonialism and the violence which it engendered. We argue that profound forms of mental distress which exist in Guyana call for an integrative and holistic practice model that contextualizes these problems through a sociogenic lens. Social workers, working collaboratively with other health-related professions, can occupy a critical role in integrating these different conceptions through developing a rights-based model of mental health where the causes of mental ill-health are understood as socially determined.
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Salud Mental , Suicidio , Humanos , Guyana/epidemiología , Servicio Social , Practicantes de la Medicina TradicionalRESUMEN
Preventing vector-borne diseases (VBDs) mainly relies on effective vector control tools and strategies, which in turn depend on population acceptance and adherence. Inspired by the abundant recent literature on SARS-COV-2, we investigate the relationship between risk perception and preventive behaviour for selected VBDs and the extent to which risk perception is determined by social norms. We use cross-sectional data collected from 497 individuals in four regions of Guyana in 2017. We use a conditional mixed process estimator with multilevel coefficients, estimated through a Generalized Linear Model (GLM) framework, applying a simultaneous equation structure. We find robust results on malaria: risk perception was significantly influenced by the risk perception of the reference group across different definitions of the reference group, hinting at the existence of social norms. Risk perception significantly increased the likelihood of passive behaviour by 4.48%. Less clear-cut results were found for dengue. This study applies quantitative social science methods to public health issues in the context of VBDs. Our findings point to the relevance of tailoring communications on health risks for VBDs to groups defined at the intersection of socio-economic and demographic characteristics. Such tailored strategies are expected to align risk perception among reference groups and boost preventive behaviour.
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COVID-19 , Enfermedades Transmitidas por Vectores , Humanos , Guyana/epidemiología , Normas Sociales , Estudios Transversales , COVID-19/epidemiología , COVID-19/prevención & control , SARS-CoV-2 , Enfermedades Transmitidas por Vectores/prevención & control , PercepciónRESUMEN
Seed dispersal is widely considered an important mechanism for the conservation of plant diversity. In tropical regions, over 80% of woody plant species are dispersed by vertebrates, often through the consumption of fruits. Our understanding of what drives interactions between vertebrates and fruits is limited. Through a systematic literature search, we compiled a database of fruit and seed traits and vertebrate-fruit interactions for tree and vertebrate species occurring in the Guianas, with the aim of facilitating research into seed dispersal and seed predation of tree species in the Guianas. The database was compiled by extracting data from 264 published sources. It consists of 21,082 records, of which 19,039 records contain information about 19 different fruit and seed traits belonging to 1622 different tree species. The other 2043 records contain information on vertebrate-fruit interactions between 161 vertebrate species and 464 tree species. Our analyses showed a taxonomic bias, particularly in the interaction data, toward large-bodied vertebrates, with most interactions recorded for the bearded saki (Chiropotes chiropotes), followed by the lowland tapir (Tapirus terrestris). For plants we found an overrepresentation of the Sapotaceae and Moraceae families and an underrepresentation of the Rubiaceae, Myrtaceae, and Lauraceae families in the interactions. There are no copyright restrictions on the data set; please cite this publication when using these data.
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Pitheciidae , Dispersión de Semillas , Animales , Conducta Alimentaria , Guyana Francesa , Frutas , Guyana , Plantas , Semillas , Suriname , Árboles , VertebradosRESUMEN
This study examined the mediating role of parental cognitive engagement and parental guidance on the associations between family socioeconomic and home environment resource risk factors and children's literacy and social skills in Guyana. The sample consisted of 1208 families from diverse ethnic and socioeconomic backgrounds drawn from the 2019 to 2020 country-level UNICEF MICS data. Caregivers provided assessments of socioeconomic conditions, educational resources in the home environment, cognitive engagement, parental guidance and children's literacy and social skills. Family socioeconomic risk had an indirect association with social skills through cognitive engagement. Home environment educational resource risk had indirect associations with children's literacy and social skills through parental guidance. Findings are discussed in terms of identifying protective factors within families in low- and middle-income Caribbean countries that can better inform intervention efforts geared at reducing risks to childhood development.
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Alfabetización , Habilidades Sociales , Humanos , Niño , Guyana , Padres/psicología , Factores de Riesgo , CogniciónRESUMEN
The actual diversity of anurans occurring in Amazonia remains only partly described. This is notably the case of the species of the genus Allobates despite a fast rate of species description in this genus during the last decade. This increasing taxonomic effort has been particularly facilitated by the availability of DNA sequences throughout the region. These data suggest for instance the existence of three lineages in the Guiana Shield that may correspond to unnamed species. We examined morphology and calls of these putative species and compared them to related nominal species, which confirmed that two of these lineages not only differ genetically but also morphologically and bioacoustically. These two species are thus named and described herein. Allobates vicinus sp. nov. from northern Suriname forms a clade with another candidate species from southern Suriname and Northern Pará, (Brazil) and with A. granti that occurs in French Guiana. Allobates ripicolus sp. nov. occurs throughout the eastern Guiana Shield and is nested within the A. tapajos complex which otherwise occurs in southeastern Amazonia and comprises A. tapajos and A. kamilae, along with three additional candidate species.
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Anuros , Animales , GuyanaRESUMEN
An iterative analysis of Imparfinis, combining phylogenetic analysis based on cytochrome oxidase gene and multivariate morphometrics, revealed a new cryptic species from the Andean tributaries of the Orinoco River basin, which is described here. The new species is sister to a clade constituted by Imparfinis hasemani and Imparfinis pijpersi, both from the river basins of the Guiana Shield, being also the most geographically proximate species. Nonetheless, the new species is most similar in general appearance to Imparfinis guttatus from the Madeira and Paraguay River drainages, being almost undistinguishable by conventional characters of external morphology, differing only by morphometric attributes overall. The new species can be distinguished from the remaining congeners by a unique combination of characters, including lower lobe of caudal fin darker than upper lobe, maxillary barbel reaching or surpassing pelvic-fin insertion, 12-15 gill rakers on first gill arch, 40-42 total vertebrae and 9-10 ribs. The new species constitutes the only representative from the Orinoco River basin belonging to Imparfinis sensu stricto.
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Bagres , Animales , Filogenia , Bagres/genética , Ríos , Branquias , GuyanaRESUMEN
Guyana is one of the poorest countries in South America, with the highest rate of cardiovascular mortality on the continent. As is the case in many low- and middle-income countries, cardiovascular care is available through the private sector but is not accessible to much of the urban and rural poor. We present the 10-year experience of the Guyana Program to Advance Cardiac Care (GPACC), an academic partnership aiming to provide high-quality, equitable cardiovascular care in Georgetown's only public hospital. We discuss the implementation of a cardiac care program using the World Health Organization Framework for Action, outlining vital components for care delivery in resource-limited settings. GPACC was able to demonstrate that targeted investment, education of clinicians, and cohesive healthcare delivery strategies can contribute to sustainable service delivery for Guyana's largest burden of disease. This structured approach may provide lessons for implementation of similar programs in other resource-limited settings. Highlights: In many LMICs, specialized cardiovascular care is available in the private, but not public, sector.The WHO Framework for Action can guide development of sustainable programs in low-resource settings.GPACC can serve as a successful and innovative model for delivery of sustainable cardiovascular care.
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Atención a la Salud , Países en Desarrollo , Humanos , Guyana , América del Sur , Calidad de la Atención de SaludRESUMEN
The species of the water scavenger beetle genus Oocyclus Sharp are reviewed for the Guiana Shield region of South America. Seven species are recorded, including one here described as new: Oocyclus paraiso sp. n. from the Brazilian state of Pará. New records of previously described species are also reported for Brazil, French Guiana, Guyana, and Suriname. The aedeagus of O. coromoto Short & García is illustrated for the first time. As with all other known members of the genus, all Guiana Shield species are hygropetric habitat specialists. A key to the Oocyclus of the Guiana Shield is provided.
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Escarabajos , Animales , Guyana , AguaRESUMEN
A virtual point-of-care ultrasound (POCUS) education program was initiated to introduce handheld ultrasound technology to Georgetown Public Hospital Corporation in Guyana, a low-resource setting. We studied ultrasound competency and participant satisfaction in a cohort of 20 physicians-in-training through the urology clinic. The program consisted of a training phase, where they learned how to use the Butterfly iQ ultrasound, and a mentored implementation phase, where they applied their skills in the clinic. The assessment was through written exams and an objective structured clinical exam (OSCE). Fourteen students completed the program. The written exam scores were 3.36/5 in the training phase and 3.57/5 in the mentored implementation phase, and all students earned 100% on the OSCE. Students expressed satisfaction with the program. Our POCUS education program demonstrates the potential to teach clinical skills in low-resource settings and the value of virtual global health partnerships in advancing POCUS and minimally invasive diagnostics.
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Educación a Distancia , Evaluación Educacional , Humanos , Estudios de Cohortes , Guyana , UltrasonografíaRESUMEN
Using models of risk and resilience as a guide, this study examined the mediating role of constructive conflict behaviors on the associations between maternal depressive symptoms, intimate partner violence (IPV), and child behavior problems. The nature of the mediation pathways was also examined for two groups of families, one experiencing high and another experiencing low levels of partner social support. Participants included 196 mothers and their preschool-aged children from diverse ethnic and socioeconomic backgrounds in Guyana. Constructive conflict behaviors partially mediated the link between maternal depressive symptoms and children's externalizing behaviors. Maternal depressive symptoms and physical intimate partner violence were directly related to children's internalizing behaviors. Constructive conflict behaviors were not a mediator of the association between risk factors and children's behavioral outcomes for families experiencing high or low levels of partner social support. In the context of families experiencing high partner social support, constructive conflict behaviors appeared to be more effective in reducing children's externalizing problem behaviors. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
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Violencia de Pareja , Problema de Conducta , Preescolar , Femenino , Humanos , Niño , Guyana , Depresión , MadresRESUMEN
Snakebite envenomation is a relevant medical hazard in French Guiana and Martinique, two French territories in the Americas. All snakebite envenomations in Martinique are inflicted by the endemic viperid species Bothrops lanceolatus, whereas Bothrops atrox is responsible for the majority of snakebites in French Guiana, although other venomous snake species also occur in this South American territory. This review summarizes some of the key aspects of the natural history of these species, as well as of their venom composition, the main clinical manifestations of envenomations, and their treatment by antivenoms. B. atrox venom induces the typical set of clinical manifestations characteristic of Bothrops sp. venoms, i.e., local tissue damage and systemic alterations associated with coagulopathies, hemorrhage, hemodynamic alterations, and acute kidney injury. In the case of B. lanceolatus venom, in addition to some typical features of bothropic envenomation, a unique and severe thrombotic effect occurs in some patients. The pathogenesis of this effect remains unknown but may be related to the action of venom components and inflammatory mediators on endothelial cells in the vasculature. A monospecific antivenom has been successfully used in Martinique to treat envenomations by B. lanceolatus. In the case of French Guiana, a polyvalent antivenom has been used for some years, but it is necessary to assess the preclinical and clinical efficacy against viperid venoms in this country of other antivenoms manufactured in the Americas.
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Bothrops , Venenos de Crotálidos , Mordeduras de Serpientes , Animales , Mordeduras de Serpientes/tratamiento farmacológico , Mordeduras de Serpientes/epidemiología , Antivenenos/uso terapéutico , Guyana , Martinica , Células Endoteliales , InmunoterapiaRESUMEN
The Neotropics have recently emerged as an important region for studies of tropical ectomycorrhizal (ECM) fungi. Specific neotropical areas with high ECM host tree densities have ECM fungal diversities rivaling those of higher-latitude forests. Some forests of the Guiana Shield are dominated by endemic ECM trees of the Fabaceae, including species of Dicymbe (subfam. Detarioideae), Aldina (subfam. Papilionoideae), and Pakaraimaea (Cistaceae). One of the most species-rich ECM fungal families present in each of these systems is Russulaceae. Long-term sampling in forests in Guyana's Pakaraima Mountains has revealed a number of species of the Russulaceae genera Lactarius, Lactifluus, and Russula. In this study, we document a previously unknown, distinct lineage of Lactarius subg. Plinthogalus containing eight species from the Guiana Shield. Here, we describe five of these species from Guyana as new to science: Lactarius humiphilus, Lactarius mycenoides, Lactarius guyanensis, Lactarius dicymbophilus, and Lactarius aurantiolamellatus. Morphological descriptions, habit, habitat, and known distribution are provided for each new species. Sequence data for the barcode internal transcribed spacer (ITS) locus are provided for types and most other collections of the new taxa, and a molecular phylogenetic analysis based on the ITS, 28S, and RPB2 (second-largest subunit of the RNA polymerase II) loci across the genus Lactarius corroborates their morphology-based infrageneric placement. The discovery of this lineage changes our insights into the biogeography and evolutionary history of Lactarius subg. Plinthogalus.