Neotropical Dry Forests Research Articles

Floral morphology and pollen placement strategies of bat-pollinated flowers: a comparative analysis within a guild of chiropterophilous plants in a neotropical dry forest

BackgroundSynchronopatric plant species, coexisting and flowering simultaneously, often engage in intense competition for pollen deposition on shared pollinators. This study focuses on the intricate dynamics of chiropterophilous flowers within the neotropical bat-pollination plant guild, specifically investigating the mechanical fit of reproductive structures to pollinating bats at the community level.MethodsUtilizing a diverse guild of bat-pollinated plant species from the Caatinga, the largest dry forest in the Neotropics, our research integrates various key components. Initially, we identified specific contact sites for floral reproductive structures on the bat's body, exploring diverse pollen placement strategies. Subsequent efforts involved characterizing floral traits within the guild and examining their associations with different pollen placement strategies. Precision in the contact of floral reproductive structures was estimated, and findings were integrated by associating pollen placement strategies and precision with the investment in pollen production.ResultsWe found that certain bat body parts, particularly the face and neck, were more frequently contacted by reproductive structures. The three identified categories of pollen placement strategies were evenly distributed among plant species, each linked to specific floral traits. Notably, the absence of oriented herkogamy prevailed in 70% of the species. Morphometric analyses unveiled significant variations in operative distances among species, emphasizing exceptional variability in certain outliers. While precision in pollen transfer was influenced by key factors, surprisingly, investment in pollen production did not differ among plants with distinct pollen placement strategies. Furthermore, it showed no correlation with fundamental accuracy.ConclusionsThe subsequent exploration delves into the intricate associations between distinct floral characteristics and various pollen placement strategies, shaping the complex pollen landscape on bat bodies. This research provides valuable insights into the community-level dynamics of chiropterophilous flowers in the Caatinga Dry Forest, emphasizing the role of different pollen deposition strategies in facilitating the coexistence of multiple plant species within the chiropterophilous guild.

Assessing two decades of landscape greenness in relation to temperature and precipitation in a tropical dry forest of Northwestern Mexico

Canopy greenness is an indicator of ecosystem primary productivity, which is often limited by temperature and precipitation. Changes in vegetation greening have been reported mostly at global scales. However, we still have a poor understanding of vegetation greening patterns and drivers for major vegetation types, such as the tropical dry forest, one of the most extensive vegetation types in Mexico. Here, we analyze two decades of interannual variation in greenness and its relationship to temperature and precipitation in the northmost neotropical dry forest occurring in Northwestern Mexico. We constructed time-series linear regression models using standardized anomalies with z-scores (i.e., standard deviations away from the long-term mean) for the Normalized Difference Vegetation Index (NDVI) and the climate data from 2001 to 2021. Our best models indicate both temperature and precipitation exert positive effects on vegetation greenness, particularly from a lagged effect perspective, as retained predictors were the accumulated precipitation of two monsoon (summer) seasons and previous year mean temperature. The lowest levels of landscape greenness seem connected to prolonged droughts and extreme frost events. In fact, a switch from negative to positive NDVI anomalies was observed in the years following the February 2011 extreme frost that affected much of North America, including northern Mexico. Notable, under the stricter statistical criterion of −1.7 ≥ z score ≥ 1.7, only climatic variables presented very-extreme anomalies and these were not necessarily linked to a very-extreme response in landscape greenness. However, considering the criterion of −1.3 ≥ z score ≥ 1.3, we identified several extreme NDVI anomalies and their corresponding climatic anomaly. Therefore, more flexible statistical criteria might reveal climate extremes of ecological and social relevance. Our overall findings have implications for forest and climate risk management, particularly as extreme climatic anomalies are expected to continue increasing in light of climate change.

Activity patterns of the white-tailed deer (Odocoileus virginianus) in a neotropical dry forest: changes according to age, sex, and climatic season

Activity patterns of the white-tailed deer (Odocoileus virginianus) in a neotropical dry forest: changes according to age, sex, and climatic season

Thresholds and Alternative States in a Neotropical Dry Forest in Response to Fire Severity

Thresholds and Alternative States in a Neotropical Dry Forest in Response to Fire Severity

Thresholds and alternative states in a Neotropical dry forest in response to fire severity.

Neotropical xerophytic forest ecosystems evolved with fires that shaped their resilience to disturbance events. However, it is unknown whether forest resilience to fires persists under a new fire regime influenced by anthropogenic disturbance and climate change. We asked whether there was evidence for a fire severity threshold causing an abrupt transition from a forest to an alternative shrub thicket state in the presence of typical postfire management. We studied a heterogeneous wildfire event to assess medium-term effects (11 years) of varying fire severity in a xerophytic Caldén forest in central Argentina. We conducted vegetation surveys in patches that were exposed to low (LFS), medium (MFS), and high (HFS) fire severities but had similar prefire woody canopy cover. Satellite images were used to quantify fire severity using a delta Normalized Burning Ratio (dNBR) and to map prefire canopy cover. Postfire total woody canopy cover was higher in low and medium than high severity patches, but the understory woody component was highest in HFS patches. The density of woody plants was over three times higher under HFS than MFS and LFS due to the contribution of small woody plants to the total density. Unlike LFS and MFS patches, the small plants in HFS patches were persistent, multistem shrubs that resulted from the resprouting of top-killed Prosopis caldenia trees and, more importantly, from young shrubs that probably established after the wildfire. Our results suggest that the Caldén forest is resilient to fires of low to moderate severities but not to high-severity fires. Fire severities with dNBR values > ~600 triggered an abrupt transition to a shrub thicket state. Postfire grazing and controlled-fire treatments likely contributed to shrub dominance after high-severity wildfire. Forest to shrub thicket transitions enable recurring high-severity fire events. We propose that repeated fires combined with grazing can trap the system in a shrub thicket state. Further studies are needed to determine whether the relationships between fire and vegetation structure examined in this case study represent general mechanisms of irreversible state changes across the Caldenal forest region and whether analogous threshold relationships exist in other fire-prone woodland ecosystems.

Paleomodeling reveals priority areas for conservation of stingless bees from the Caatinga region, a neotropical dry forest

Paleomodeling reveals priority areas for conservation of stingless bees from the Caatinga region, a neotropical dry forest

A Novel Isoprene Synthase from the Monocot Tree Copernicia prunifera (Arecaceae) Confers Enhanced Drought Tolerance in Transgenic Arabidopsis.

The capacity to emit isoprene, among other stresses, protects plants from drought, but the molecular mechanisms underlying this trait are only partly understood. The Arecaceae (palms) constitute a very interesting model system to test the involvement of isoprene in enhancing drought tolerance, as their high isoprene emissions may have contributed to make them hyperdominant in neotropical dry forests, characterized by recurrent and extended periods of drought stress. In this study we isolated and functionally characterized a novel isoprene synthase, the gene responsible for isoprene biosynthesis, from Copernicia prunifera, a palm from seasonally dry tropical forests. When overexpressed in the non-emitter Arabidopsis thaliana, CprISPS conferred significant levels of isoprene emission, together with enhanced tolerance to water limitation throughout plant growth and development, from germination to maturity. CprISPS overexpressors displayed higher germination, cotyledon/leaf greening, water usage efficiency, and survival than WT Arabidopsis under various types of water limitation. This increased drought tolerance was accompanied by a marked transcriptional up-regulation of both ABA-dependent and ABA-independent key drought response genes. Taken together, these results demonstrate the capacity of CprISPS to enhance drought tolerance in Arabidopsis and suggest that isoprene emission could have evolved in Arecaceae as an adaptive mechanism against drought.

Assessment of the Quality, Chemometric and Pollen Diversity of Apis mellifera Honey from Different Seasonal Harvests.

The parameters for assessing the quality of honey produced by Apis mellifera are standardized worldwide. The physicochemical properties of honey might vary extensively due to factors such as the geographical area where it was produced and the season in which it was harvested. Little information is available on variations in honey quality among different harvest periods in tropical areas, and particularly in neotropical dry forests. This study describes variations in seventeen physicochemical parameters and the pollen diversity of honey harvested from beehives during the dry season in February, March, and April 2021, in the dry arc of Panama. Potassium is the most abundant mineral in honey samples, and its concentration increases during the harvest period from February to April. A PCA analysis showed significant differences among the samples collected during different harvest periods. The pollen diversity also differs among honey samples from February compared with March and April. The results indicate that climatic conditions may play an important role in the quality of honey produced in the dry arc of Panama. Furthermore, these results might be useful for establishing quality-control parameters of bee honey produced in Panama in support of beekeeping activities in seasonal wet-dry areas of the tropics.

Bat functional traits associated with environmental, landscape, and conservation variables in Neotropical dry forests

Tropical dry forests are among the most threatened ecosystems worldwide. Bats' role in those ecosystems is critical because of multiple bat-mediated processes. Such processes are strongly related to bats' functional traits. However, it is poorly known which bat's functional traits could relate to variations in environmental conditions in tropical dry forests. In this study, we tested the hypotheses that bat functional traits would be significantly associated with landscape variables, climatic variables, and land-use intensity. For testing these hypotheses, we used data from phyllostomid and mormoopid bats captured in mist nets and data from non-phyllostomid insectivorous bat species registered by passive acoustic monitoring. We considered six functional traits for phyllostomid and mormoopid bats, and for non-phyllostomid insectivorous bats, we added two echolocation parameters. We measured five environmental variables, two of local climate (daily maximum temperature and wind speed) and three of landscape features (total area of water and closeness, probability of finding caves, and conservation status). The relationships between bat functional traits and environmental variables were evaluated using the RLQ and the fourth-corner analysis. We captured 360 individuals belonging to 14 species with mist nets (Phyllostomidae and Mormoopidae), and we identified 18 species and six sonotypes with acoustic sampling (Emballonuridae, Mormoopidae, Molossidae, Natalidae, Noctilionidae, and Vespertilionidae). We found that bats' functional traits related to environmental conditions were pulse structure, diet, vertical foraging stratification, and trophic level, although these relationships varied among bats' ecological roles. The hematophagous were related to water bodies' closeness, and animalivorous bats, mostly mormoopids, showed a relationship with the probability of finding caves. Insectivorous bats that mostly forage on the canopy and emit qCF calls were significantly related to more conserved sites, and bats that emit qCF pulses were significantly associated with less area covered by water. Our findings provide insights into how bat functional traits vary in their relationships with environmental conditions in harsh environments such as dry forests.

Arbuscular mycorrhizal fungi associated with the rhizosphere of an endemic terrestrial bromeliad and a grass in the Brazilian neotropical dry forest.

Arbuscular mycorrhizal fungi form symbiotic associations with 80-90% of all known plants, allowing the fungi to acquire plant-synthesized carbon, and confer an increased capacity for nutrient uptake by plants, improving tolerance to abiotic and biotic stresses. We aimed at characterizing the mycorrhizal community in the rhizosphere of Neoglaziovia variegata (so-called `caroa`) and Tripogonella spicata (so-called resurrection plant), using high-throughput sequencing of the partial 18S rRNA gene. Both plants are currently undergoing a bioprospecting program to find microbes with the potential of helping plants tolerate water stress. Sampling was carried out in the Caatinga biome, a neotropical dry forest, located in northeastern Brazil. Illumina MiSeq sequencing of 37 rhizosphere samples (19 for N. variegata and 18 for T. spicata) revealed a distinct mycorrhizal community between the studied plants. According to alpha diversity analyses, T. spicata showed the highest richness and diversity based on the Observed ASVs and the Shannon index, respectively. On the other hand, N. variegata showed higher modularity of the mycorrhizal network compared to T. spicata. The four most abundant genera found (higher than 10%) were Glomus, Gigaspora, Acaulospora, and Scutellospora, with Glomus being the most abundant in both plants. Nonetheless, Gigaspora, Diversispora, and Ambispora were found only in the rhizosphere of N. variegata, whilst Scutellospora, Paraglomus, and Archaeospora were exclusive to the rhizosphere of T. spicata. Therefore, the community of arbuscular mycorrhizal fungi of the rhizosphere of each plant encompasses a unique composition, structure and modularity, which can differentially assist them in the hostile environment.

Seasonality regulates the structure and biogeochemical impact of ectomycorrhizal fungal communities across environmentally divergent neotropical dry forests

Abstract Ectomycorrhizal (ECM) symbioses support forest functioning globally, yet both the structure and function of ECM fungal communities in seasonally dry neotropical forests (SDTFs), known for extreme heterogeneity in vegetation and edaphic properties, remain under characterized. Here, we evaluated the relative influences of seasonal versus spatial variation in ECM fungal community structure in soils from four environmentally divergent SDTFs. We also assessed the importance of biotic and abiotic drivers of SDTF ECM fungal community structure at regional scales, as well as ECM impacts on soil carbon (C) and nitrogen (N) cycling. ECM fungal frequency, relative abundance and richness all increased in the wet season, but spatial rather than seasonal effects explained more variation in community composition. Across the four SDTFs investigated, differences in tree communities drove ECM fungal community turnover more than geographic distances, site abiotic conditions or soil chemistry. Although soil moisture and ECM tree basal area were stronger predictors of soil biogeochemistry, incorporating ECM fungal community composition and relative abundance added explanatory power to models of soil C and N cycling in the wet season. Synthesis: Our results highlight the importance of seasonality and plant community composition in shaping different aspects of SDTF ECM fungal community structure and diversity as well as the potential for both the plant and fungal components of ECM symbioses to impact soil functioning across heterogenous SDTFs. Furthermore, our findings suggest that alterations in SDTF plant community composition due to climate or land‐use change will have important consequences for ECM fungal diversity and associated effects on soil biogeochemical cycling.

Germination niche of a neotropical dry forest species: seed osmotic stress and recovery

Abstract: Erythrina velutina Willd is a native Fabaceae with wide occurrence, mainly in the Caatinga Domain with multiple uses. This study aimed to compare the vulnerability/tolerance of seeds of four accessions of E. velutina to osmotic stresses. Four replications were conducted with 25 seeds, germinated in osmotic solutions of NaCl or PEG up to -1.73 MPa. Seeds that did not germinate after 14 days were recovered in distilled water. Obtained data were fitted in Boltzmann curves and t50 and synchrony were evaluated. A probit analysis was performed, and hydrotime and halotime models were constructed. In distilled water, the germination curve was similar for all accessions. When the concentration of salt or PEG in the substrate increased, the accessions differentiated into two groups. Two accessions - Jutaí 2012 and Jutaí 2015 - maintained high germination up to -0.86 MPa NaCl, while Caboclo 2008 and Caiçara 2011 accessions presented a lower germination speed. The hydrotime and halotime analyses separated the germination response of accessions according to their physiological quality and tolerance to osmotic and saline conditions. Seeds viability was maintained at both stresses, since germination was reestablished at distilled water, thus constituting a crucial response for this species’ survival and conservation.

Predicting co-distribution patterns of parrots and woody plants under global changes: The case of the Lilac-crowned Amazon and Neotropical dry forests

Global climate and land-use changes are the most significant causes of the current habitat loss and biodiversity crisis. Although there is information measuring these global changes, we lack a full understanding of how they impact community assemblies and species interactions across ecosystems. Herein, we assessed the potential distribution of eight key woody plant species associated with the habitat of the endangered Lilac-crowned Amazon (Amazon finschi) under global changes scenarios (2050′s and 2070′s), to answer the following questions: (1) how do predicted climate and land-use changes impact these species’ individual distributions and co-distribution patterns?; and (2) how effective is the existing Protected Area network for safeguarding the parrot species, the plant species, and their biological interactions? Our projections were consistent identifying the species that are most vulnerable to climate change. The distribution ranges of most of the species tended to decrease under future climates. These effects were strongly exacerbated when incorporating land-use changes into models. Even within existing protected areas, >50 % of the species’ remaining distribution and sites with the highest plant richness were predicted to be lost in the future under these combined scenarios. Currently, both individual species ranges and sites of highest richness of plants, shelter a high proportion (ca. 40 %) of the Lilac-crowned Amazon distribution. However, this spatial congruence could be reduced in the future, potentially disrupting the ecological associations among these taxa. We provide novel evidence for decision-makers to enhance conservation efforts to attain the long-term protection of this endangered Mexican endemic parrot and its habitat.

Prediction of Soil Erodibility by Diffuse Reflectance Spectroscopy in a Neotropical Dry Forest Biome

The USLE and the RUSLE are two common erosion prediction models that are used worldwide, and soil erodibility (K-factor) is one parameter used to calculate them. The objectives of this study were to investigate the variability of soil-erodibility factors under different soil-texture classes and evaluate the efficiency of diffuse reflectance spectroscopy (DRS) in the near-infrared range at predicting the USLE and RUSLE K-factors using a partial least squares regression analysis. The study was conducted in Fluvisols in dry tropical forest (the Caatinga). Sampling was undertaken in the first 20 cm of soil at 80 sites distributed 15 m apart on a 70 m × 320 m spatial grid. Results show that the clay fraction is represented mainly by 2:1 phyllosilicates. Soil organic matter content is low (<0.2%), which is typical of tropical dry forests, and this is reflected in the high values of the calculated USLE and RUSLE K-factors. An empirical semivariogram was used to investigate the spatial dependence of both K-factors. Pedometric modeling showed that DRS can be used to predict both USLE (R2adj = 0.53; RMSE = 8.37 10−3 t h MJ−1 mm−1) and RUSLE (R2adj = 0.58; RMSE = 6.78 10−3 t h MJ−1 mm−1) K-factors.

First Report of Blood Parasites in Black-Capped Sparrow (Arremon abeillei) from Neotropical Dry Deciduous Forest.

Avian haemosporidian parasites (Order: Haemosporida) are a diverse group of microorganisms that spend part of their life cycle in the erythrocytes of avian hosts. Parasite presence has been confirmed in all Ecuadorian regions, but some ecosystems, such as the deciduous dry forest of the Coastal region, have not been evaluated for parasite presence. Data on presence or absence, and prevalence, of haemosporidian blood parasites were obtained from avian blood samples collected in two different dry deciduous forests in Guayaquil, Ecuador: Bosque Protector Prosperina and Área Nacional de Recreación Parque Lago. Mist netting was performed between December 2018 and September 2019; blood smears were prepared from blood taken from 35 individuals of 20 bird species and all samples were analyzed by optical microscope observation. Most species showed no evidence of parasite infection, but haemosporidia were found on a blood smear obtained from a Black-capped Sparrow, Arremon abeillei (Passerelleidae), confirming this species as a newly discovered host of blood parasites.

Precipitation and temperature shape the biogeography of arbuscular mycorrhizal fungi across the Brazilian Caatinga

AbstractAimDeterministic and neutral processes shape the biogeography of fungi. Arbuscular mycorrhizal fungi (AMF), an important group of plant root symbionts, remains poorly studied in the Neotropics. Here, we provided the first molecular survey of AMF diversity and tested whether the environment or space shapes AMF biogeography along a 12° latitudinal transect in the Brazilian Caatinga, a unique tropical dry forest ecoregion.LocationCaatinga, Brazil.TaxonArbuscular mycorrhizal fungi (Glomeromycotina).MethodsSoil and root samples were collected across a latitudinal transect of 1500 km within the Brazilian Caatinga. AMF communities were characterized using Illumina LSU amplicon sequencing. Operational taxonomic unit (OTU) richness, composition and phylogenetic niche conservatism were assessed using univariate and multivariate analyses, and the potential for new taxa discovery was assessed with BLAST analysis against reference and environmental sequences sets.ResultGlomeraceae was the most abundant and diverse family, resembling more dry Saharo‐Arabian and Australian realms or European croplands than other tropical forests from South America, but 10% of the OTUs could be taxa new to science, especially within Archaeospora, Claroideoglomus, Acaulospora, Gigaspora, Dentiscutata and Redeckera. AMF communities showed strong biogeographical structure inconsistent with a classical latitudinal diversity gradient, which further differed between soil and roots. Soil AMF biogeography best correlated with precipitation; community composition converged and richness increased towards both ends of the latitudinal transect where precipitation increased. Root AMF biogeography correlated to temperature, with decreasing diversity at higher temperatures. We found no evidence of phylogenetic niche conservatism.Main conclusionsNiche‐based processes driven by regional climate, most importantly precipitation and temperature, shape AMF biogeography across the Caatinga, with niche divergence among closely related AMF taxa. Given the expected future decrease in precipitation and increase in temperature, climate change may strongly affect the unique and yet unknown AMF biodiversity in neotropical dry forests.

Changes in the potential distribution of valuable tree species based on their regeneration in the Neotropical seasonal dry forest of north-western Argentina

SummaryThe distribution of regeneration makes it possible to assess whether populations of tree species will maintain or change their distributions. For Neotropical dry forests there is little information on the potential changes in the distribution of tree species. Here, we evaluate the potential distributions of adults and seedlings of eight timber tree species of the Piedmont Forest of north-western Argentina by recording the presence of seedlings and adults in plots and modelling with MaxEnt software using three bioclimatic variables. The potential distribution areas of seedlings and adults and the percentage of overlap of seedlings with respect to adults were calculated. The potential distribution for adults was 694 457 ± 62 535 ha, and this figure was 656 564 ± 194 769 ha for seedlings. The potential distribution of seedlings of Calycophyllum multiflorum covered the smallest area (184 496 ha) and had the least overlap with the adults (18%). The difference in the overlap of the potential distribution areas between adults and seedlings suggests that there could be changes in the future distribution of this tree species and C. multiflorum should therefore be the focus of conservation strategies so that the species can follow its bioclimatic niche as the climate changes.

Contrasting Effects of Chronic Anthropogenic Disturbance on Activity and Species Richness of Insectivorous Bats in Neotropical Dry Forest

For prioritizing conservation actions, it is vital to understand how ecologically diverse species respond to environmental change caused by human activity. This is particularly necessary considering that chronic human disturbance is a threat to biodiversity worldwide. Depending on how species tolerate and adapt to such disturbance, ecological integrity and ecosystem services will be more or less affected. Bats are a species-rich and functionally diverse group, with important roles in ecosystems, and are therefore recognized as a good model group for assessing the impact of environmental change. Their populations have decreased in several regions, especially in the tropics, and are threatened by increasing human disturbance. Using passive acoustic monitoring, we assessed how the species-rich aerial insectivorous bats—essential for insect suppression services—respond to chronic human disturbance in the Caatinga dry forests of Brazil, an area potentially harboring ca. 100 bat species (nearly 50% are insectivorous), but with > 60% its area composed of anthropogenic ecosystems under chronic pressure. Acoustic data for bat activity was collected at research sites with varying amounts of chronic human disturbance (e.g., livestock grazing and firewood gathering). The intensity of the disturbance is indicated by the global multi-metric CAD index (GMDI). Using Animal Sound Identifier (ASI) software, we identified 18 different bat taxon units. Using Hierarchical Modeling of Species Communities (HMSC), we found trends in the association of the disturbance gradient with species richness and bat activity: species richness was higher at sites with higher human disturbance, whereas bat activity decreased with increasing human disturbance. Additionally, we observed taxon-specific responses to human disturbance. We conclude that the effects of chronic anthropogenic disturbance on the insectivorous bat fauna in the Caatinga are not homogeneous and a species-specific approach is necessary when assessing the responses of local bats to human disturbances in tropical dry forests, and in other biomes under human pressure.

Bursera fruit traits as drivers of fruit removal by flycatchers

Fruit size and shape are key traits that affect the interactions between plants and their seed dispersers within communities. Yet, the co-adaptive morphological links between fruits and bird seed dispersers within highly biodiverse Neotropical dry forests are still poorly understood. In this study, we evaluated the relationship between the morphometric fruit traits of Bursera, a group of dominant trees in tropical dry forests, and the morphometric body traits of flycatcher birds of the Tyrannidae family, their main seed dispersers. We found that the largest bird species primarily consumed large- and medium-sized fruits, while smaller birds targeted plants with small- and medium-sized fruits. Migratory flycatchers were the core species involved in Bursera fruit removal, except in Bursera species fruiting during the rainy season, when these birds are not present. Also, small-sized fruits with an oblong shape tended to be removed more frequently by small-sized birds, while large-oblong fruits tended to be more consumed by larger birds. According to body traits, bill width, tarsus, and wing length had significant effects on fruit removal. Wider-billed Tyrannus, Myiarchus, and Myiodynastes species removed almost half of the fruits. The Myiarchus genus showed the longest tarsus and removed up to 58% of all fruits. The Tyrannus species, which rely on flight to obtain food, showed the greatest wing length. Our findings suggest that morphological traits of Bursera fruits such as shape and size may be fitted to interact with the body traits of their bird dispersers. Studies on seasonally dynamic bird-plant interactions are crucial for a better understanding of the ecological and evolutionary drivers in Neotropical dry forests.

A New Phylogenetic Hypothesis for Cereinae (Cactaceae) Points to a Monophyletic Subtribe

Abstract— Cereinae comprises 14 genera distributed in Neotropical dry forest formations such as in the Caatingas of northeastern Brazil or in rocky outcrops in the north of southeastern Brazil. Historically, the taxonomy of the group has been very controversial, especially regarding generic circumscriptions, and phylogenetic relationships within the group are still poorly understood. To investigate the delimitation of the subtribe and infra-subtribal relationships, we performed a phylogenetic analysis including 50 taxa representing 13 genera using one nuclear (PhyC) and four cpDNA (petL-psbE, trnL-trnT, trnS-trnG, and rpl16) regions. Our results show a monophyletic Cereinae with high support in Bayesian, maximum parsimony, and maximum likelihood analyses based on combined matrices. Although our results expand the knowledge of generic relationships, we emphasize the need for further molecular phylogenetic studies combined with ecological evidence to clarify relationships at the more inclusive nodes of the subtribe.