Mar Mountain Research Articles

Montane diversification as a mechanism of speciation in neotropical butterflies.

The mountains in the Atlantic Forest domain are environments that harbor a high biodiversity, including species adapted to colder climates that were probably influenced by the climatic variations of the Pleistocene. To understand the phylogeographic pattern and assess the taxonomic boundaries between two sister montane species, a genomic study of the butterflies Actinote mantiqueira and A. alalia (Nymphalidae: Acraeini) was conducted. Analyses based on partial sequences of the mitochondrial gene COI (barcode region) failed to recover any phylogenetic or genetic structure discriminating the two species or sampling localities. However, single nucleotide polymorphisms gathered using Genotyping-by-Sequencing provided a strong isolation pattern in all analyses (genetic distance, phylogenetic hypothesis, clustering analyses, and F ST statistics) which is consistent with morphology, separating all individuals of A. alalia from all populations of A. mantiqueira. The three sampled mountain ranges where A. mantiqueira populations occur-Serra do Mar, Serra da Mantiqueira, and Poços de Caldas Plateau-were identified as three isolated clusters. Paleoclimate simulations indicate that both species' distributions changed according to climatic oscillations in the Pleistocene period, with the two species potentially occurring in areas of lower altitude during glacial periods when compared to the interglacial periods (as the present). Besides, a potential path between their distribution through the Serra do Mar Mountain range was inferred. Therefore, the Pleistocene climatic fluctuation had a significant impact on the speciation process between A. alalia and A. mantiqueira, which was brought on by isolation at different mountain summits during interglacial periods, as shown by the modeled historical distribution and the observed genetic structure.

A new species of Brachycephalus (Anura: Brachycephalidae) from the northern portion of the state of Rio de Janeiro, southeastern Brazil

Abstract Brachycephalus is a genus of small ground-dwelling anurans, endemic to the Brazilian Atlantic Forest. Recent molecular analyses have corroborated the monophyly of three species groups within this genus (B. ephippium, B. ephippium, and B. ephippium). In the meantime, the genus has been targeted as a group with recent taxonomic issues owing to its interspecific morphological similarity and genetic conservatism. Herein, we describe a new species of Brachycephalus from the northern portion of Serra do Mar mountain range, in the state of Rio de Janeiro, Brazil. It belongs to the B. ephippium species group, exhibiting moderate hyperossification of the skull and vertebral column. The new species can be distinguished from all other congeners based on morphological, acoustic, and molecular data. Furthermore, we provide information on osteology and natural history of the new species.

Myrcia tenondeporan, a new species of Myrtaceae from the Atlantic Forest in the Serra do Mar Mountains, Brazil

Myrcia sect. Eugeniopsis is one of the nine sections of Myrcia (Myrciinae, Myrteae, Myrtaceae) and includes mostly species of the current synonym genus Eugeniopsis. Using fieldwork and the analysis of herbarium collections as a basis, we describe here a new species of this section, Myrcia tenondeporan, which is endemic to the Atlantic Forest in the Serra do Mar Mountains. The new species is related to Myrcia vellozoi and Myrcia multipunctata but differs mainly in the leaf shape and size, inflorescence structure and size of floral buds.

Repeated evolution of pollination syndromes in a highly diverse bromeliad lineage is correlated with shifts in life form and habitat

AbstractMutualistic plant-pollinator interactions play a critical role in the diversification of flowering plants. The spatiotemporal correlates of such interactions can be understood in a phylogenetic context. Here, we generate ddRAD-seq data for the highly diverse Vriesea-Stigmatodon lineage to test for correlated trait evolution among pollination syndromes and life form, habitat type, and altitude. Our results show that pollination syndromes are correlated with changes in life form and habitat type. The ancestor of the Vriesea-Stigmatodon lineage was likely bat pollinated, rock dwelling and inhabited open, mid-elevation forests. Transitions from bat to hummingbird pollination are correlated with transitions to the epiphytic life form in shaded habitats, whereas bat pollination is correlated with the rock-dwelling life form and open habitats. Our dated phylogenetic tree reveals independent origins of hummingbird pollination, occurring twice in Vriesea at c. 5.8 and 5.4 Mya. The timing for the shifts in pollination syndrome coincides with geological and environmental transformations across the Serra do Mar Mountain Chain, which increased habitat heterogeneity where Vriesea and their mutualists diversified. The phylogenetic tree reinforces the non-monophyly of taxonomic sections within the genus Vriesea previously defined by flower morphology, indicating that some lineages should be treated as species complexes. This study identifies synergetic drivers of speciation in a tropical biodiversity hotspot.

Ecological, Genetic, and Phylogenetic Aspects of YFV 2017-2019 Spread in Rio de Janeiro State.

In Brazil, a yellow fever (YF) outbreak was reported in areas considered YF-free for decades. The low vaccination coverage and the increasing forest fragmentation, with the wide distribution of vector mosquitoes, have been related to yellow fever virus (YFV) transmission beyond endemic areas since 2016. Aiming to elucidate the molecular and phylogenetic aspects of YFV spread on a local scale, we generated 43 new YFV genomes sampled from humans, non-human primates (NHP), and primarily, mosquitoes from highly heterogenic areas in 15 localities from Rio de Janeiro (RJ) state during the YFV 2016-2019 outbreak in southeast Brazil. Our analysis revealed that the genetic diversity and spatial distribution of the sylvatic transmission of YFV in RJ originated from at least two introductions and followed two chains of dissemination, here named the YFV RJ-I and YFV RJ-II clades. They moved with similar dispersal speeds from the north to the south of the RJ state in parallel directions, separated by the Serra do Mar Mountain chain, with YFV RJ-I invading the north coast of São Paulo state. The YFV RJ-I clade showed a more significant heterogeneity across the entire polyprotein. The YFV RJ-II clade, with only two amino acid polymorphisms, mapped at NS1 (I1086V), present only in mosquitoes at the same locality and NS4A (I2176V), shared by all YFV clade RJ-II, suggests a recent clustering of YFV isolates collected from different hosts. Our analyses strengthen the role of surveillance, genomic analyses of YVF isolated from other hosts, and environmental studies into the strategies to forecast, control, and prevent yellow fever outbreaks.

The Facet of Human Impact: Solenopsis invicta Buren, 1972 Spreading around the Atlantic Forest

The present investigation deals with some aspects of the diversity of fire ants (Hymenoptera: Formicidae) in their native range. The Red Imported Fire Ant Solenopsis invicta is native to the tropical and subtropical inland territories of South America. In Brazil, it mainly occurs around the Pantanal region and across the Paraguay river, a region composed of grasslands which are seasonally flooded. Recent studies have evidenced this fire ant species is gradually spreading to other regions of Brazil. In the present investigation, we surveyed the molecular diversity of S. invicta populations across fragments of Atlantic Forest in São Paulo, Brazil, using mtDNA COI haplotypes. Fire ant nests were sampled along the highways lining the northern and southern slope sides of the mountain range Serra do Mar, SP, Brazil. Four haplotypes were identified (H1–H4), which were assessed for similarity to deposited records by other authors, revealing that the haplotypes H1 and H2 are likely of foreign origin through recent reintroduction via a marine port to the south of the Serra do Mar mountain range. On the other hand, the haplotypes H3 and H4, predominating among the inland samples from the northern side of the mountain range, were most similar to previous records from more central regions of Brazil. Haplotypes clustered into distinct supergroups, further pointing to the occurrence of two separate expansion waves of S. invicta in the region. We suggest the obtained pattern indicates the mountain range may function as a geographical barrier deferring gene flow.

The consequences of debris flows in Brazil: a historical analysis based on recorded events in the last 100 years

This study aims at providing an overview of the socioeconomic consequences that debris-flow events have caused in Brazil, positioning the country in the international scenario and identifying areas where targeted actions are necessary. The analysis is conducted by calculating the debris-flow mortality rate (MR) and by using the so-called F-N plots (frequency of events that have caused N or more fatalities vs. the number of fatalities), based on a compilation of debris-flow-related disasters from 1920 to 2021. In total, 45 debris-flow events were documented in the considered period, responsible for 5771 fatalities and more than 5.5 billion USD in economic losses. The Serra do Mar Mountain Range is the main site of reported debris-flow occurrences (64.5%), followed by Serra da Mantiqueira (13.3%), and Serra Geral (13.3%). Southeast Brazil (SEB) is the region most affected by debris-flow events, due to the highest population density and the development of several cities in hilly areas, such as Petrópolis (Rio de Janeiro state) and Cubatão (São Paulo state). The debris-flow MR of SEB is higher than any other region in Brazil, pushing the national debris-flow MR upwards, and the F-N curve of SEB consolidates the region as the one with the highest risk to the phenomenon, indicating a higher probability of fatal events. The F-N plots further show that debris-flow events in Brazil represent a higher societal risk than in countries such as China, Japan and Italy. While there are differences in country size and the scale effect should be considered, these results highlight the urgent need for investments in disaster prevention and preparedness programs.

End-member modeling and sediment trend analysis as tools for sedimentary processes inference in a subtropical estuary

Mathematical models based on grain size data enable identifying sediment transport sources and processes in coastal regions, helping to understand the relationship between hydrodynamic and sedimentary processes. This study applied End-Member Analysis and Grain Size Trend Analysis to a grain size database from the Paranaguá Estuarine Complex (PEC), a subtropical estuary in southern Brazil. The end-member analysis allowed identifying three grain size populations, whose spatial distribution is influenced by the dynamics between river discharge and tidal currents acting in the Paranaguá Estuarine Complex. The end-member 1 — formed by finer sediments — is mainly distributed over Antonina Bay and extends into the maximum turbidity zone. The Grain Sized Trend Analysis revealed that these sediments — derived from the weathering of rocks from the Serra do Mar mountain range system — are transported in the west-east direction by river discharge, mainly from the Cachoeira and Nhundiaquara rivers. Furthermore, our results indicate that sediments from end-members 2 and 3 — which are coarser — are distributed in the Paranaguá and Laranjeiras Bays. The transport of these sediments happens towards the center of the estuary due to wave- and tidal-generated currents.

Alluvial plain morphostratigraphy affected by recent mud and debris flows: a study in the Jacareí River basin (southern coast of Brazil)

Sedimentary records are important to understand the evolution of river systems. Morphostratigraphic studies associate sedimentary records with landforms. Mud and debris flows, common in the Serra do Mar mountain range, have a marked impact on the morphostratigraphy of adjacent alluvial plains. The objective of this study was to analyze morphostratigraphic units in an alluvial plain affected by recent mud and debris flows. The study area was the Jacareí River alluvial plain (coast of Paraná State, Brazil) which was hit by extreme gravitational events in March 2011. Geospatial and field survey data were analyzed in a GIS environment to produce a morphostratigraphic map. Units were identified in three contexts: formed earlier than 2011, formed by the 2011 mud and debris flows, and formed after 2011. The deposits instantly formed in 2011 present rocks and pebbles (debris flows) and massive sandy facies (mud flows), with a thickness of between 0.5 and 1 meter. They are easily identified due to abrupt changes in particle size, color, presence of roots, and quantity of organic matter. The results shed light on the evolutionary processes at work in the Jacareí River coastal plain landscape, withthe 2011 event representing a phase of the sedimentary cycle of alluvial plains along the Serra do Mar mountain range.

A 140-year record of environmental changes in São Sebastião, Brazil

Over the past two centuries, coastal and estuarine areas have experienced environmental stress due to rapid population growth, leading to higher demand, overexploitation, habitat transformation, and pollution, which have severe consequences on the overall ecosystem and human health. This work aims to understand historical perspectives of such environmental stress in a coastal area of São Sebastião city in the São Paulo State of Brazil, which has witnessed rapid changes in land use over the past 60–70 years. We collected eleven surface sediments and one 64 cm long core from the shallow water depth sector of the São Sebastião Channel (SSC), adjacent to the Araçá Bay region. Sediments were dominantly composed of terrestrial siliciclastic material carrying signatures of both local inputs (i.e., weathered granitic and gneissic rocks of Serra do Mar Mountain ranges) and Plata Plume sediments brought by Brazilian coastal currents. Low sediment accumulation (avg. = 0.10 cm yr−1) between 1880 and 1947 showed a stable environment followed by an abrupt increase in sedimentation (avg. = 0.84 cm yr−1) from 1947 to 2017. This approximate eight-fold increase in sedimentation after 1947 marked significant anthropogenic changes in the region, which is coincidental with major changes in land use through the construction of the port of São Sebastião (1930s) and BR-101 Highway (1980s). While recent surface sediments showed no pollution of heavy metals, anthropogenic Zn enrichment was found between 1880 and 2000. Zn enrichment was from the combined sources, e.g., agriculture activities, domestic sewage, and possibly Zn coated ship paints. Our study also indicates that planned future expansion of São Sebastião port may further increase the sedimentation rate in SSC and impact the ecosystem of Araçá Bay and SSC.

Mapping functional tree regions of the Atlantic Forest: how much is left and opportunities for conservation

SummaryMany biomes still lack an overall view of their macro-functional structure (i.e., natural biogeographical regions and zones), including the Atlantic Forest biodiversity hotspot. The effective design of protected areas depends on the spatial identification of units with ecologically distinct content, whether it be floristic, phylogenetic or functional. This study used a regionalization approach to identify the potential functional regions of the Atlantic Forest by interpolating functional data from forest remnants into the entire original occurrence area of the biome, including deforested lands. Conservation status was then estimated. Analysis of seven traits of leaf, wood, seed and plant size revealed that the biome is structured over 14 functional regions and three zones (clusters of regions). Functional regions represented specific combinations of traits rather than being characterized by extremely high or low values of a single trait. They retained an average of 29.5% of forest remnants (range: 7.63–54.66%) and 10.82% of protected areas (range: 0.35–35.78%). By analysing the functional space occupied by all regions, captured by two principal component analysis axes using the pixel-level information contained in interpolated trait maps, we showed that large parts of this space were not covered by forest remnants or protected areas and that the most represented regions had serious deficits in protected areas. Although the Serra do Mar mountain range in the south and south-east Atlantic Forest is relevant as a centre of species endemism and richness and has received considerable attention for carrying out ecological studies and creating protection areas, this range does not fully encompass the functional biodiversity of such a rich biome. Our results demonstrate the potential for combining regionalization and conservation approaches to unravel the macro-structures of biomes.

Testing palaeodrainage hypotheses in south-eastern Brazil: phylogeography of the sinistral livebearer fish of the genus Phalloceros (Cyprinodontiformes: Poeciliidae)

Abstract The ‘sinistral Phalloceros group’ consists of three species, P. aspilos, P. leptokeras and P. tupinamba, that belong to Phalloceros, a genus of freshwater fish endemic to South America. They inhabit the Paraíba do Sul Basin and coastal drainages in south-eastern Brazil. This group is diagnosed by large hooks in the medial portion of the gonopodial appendices in males and the sinistral direction of the urogenital papilla in females. We conducted a phylogeographic analysis of mitochondrial (COI and Cytb) and nuclear (RAG1) haplotypes of 36 individuals sampled from 11 localities to test the hypothesis that the biogeographic history of sinistral Phalloceros was mediated by connections of coastal basins caused by lowered sea-levels during the Quaternary. We evaluated the taxonomic status of these nominal taxa by integrating molecular species delimitation methods and morphological data. Our results suggest that the three nominal taxa are synonyms, and P. leptokeras is designated as the valid species name. The geographic expansion of the P. leptokeras lineage began in the coastal region (~2.3 Mya). The phylogeographic relationships among populations partially corroborate the palaeodrainage model, but also suggest that P. leptokeras colonized the inland Paraíba do Sul drainage, overcoming the Serra do Mar mountains.

Model-based assessment of shallow landslides susceptibility at a petrochemical site in Brazil

The Serra do Mar mountain range is the main site of shallow-landslides occurrence in Brazil. The application of physically-based models is an effective method to predict landslide susceptibility, which is of great importance in hazard assessments and urban-planning studies. Thus, the objective of this study is to compare landslide susceptibility scenarios created with SHALSTAB and SINMAP at two large watersheds (Mogi and Perequê) in Cubatão, Latin America’s largest petrochemical site. Model calibration is based on the landslide scars inventory of the 1985 event, the geotechnical parameters derived from soil samples and the topography sourced from a 5 m resolution DEM. Using the Receiver Operating Characteristics (ROC) analysis to assess model performance, SHALSTAB emerges as the best-fit model for both watersheds due to higher concentration of landslide scars in unstable areas (true positive results) and higher global accuracy. Even though SINMAP had similar degree of success, it was slightly less accurate and failed more often in the identification of potentially unstable areas. Comparative performance studies of physically-based models are fundamental to support effective and reliable hazard assessments in mountain regions, providing an outlook in how to proceed with more detailed studies.

Out of the blue: geographic variation and divergence between Azure Jays (Cyanocorax caeruleus) from two ecologically distinct ranges

ABSTRACT Underlying biological processes can often shape phenotypic variation. Although subtle, the variation in plumage colour of the Azure Jay (Cyanocorax caeruleus) has long been suggested to be of phylogeographic importance, but this hypothesis was not tested. This species’ distribution in the Atlantic Forest biome of south-eastern Brazil is divided into two ecologically distinct portions by the Serra do Mar mountain line. The availability of Parana Pine (Araucaria angustifolia) seeds is essential for the survival of Azure Jays in the western range but not in the eastern range. Here we quantify Azure Jay geographic variation using three datasets, including vocalisations, morphology and plumage colour. All available data independently supported the hypothesis of divergence between east and west. Azure Jays in the western range tend to have: (1) larger body dimensions, (2) vocalisations with lower pitch and entropy, and (3) a greenish-blue plumage, than those in the eastern range. Based on the available data on this species’ ecology, life history and sociality, we discuss how features from the western range could indicate specialisation in habitat use. We discuss potential links between our results and the past of the Atlantic Forest and the implications for this species conservation in a highly threatened habitat. Finally, we highlight the pressing need for demographic and molecular evidence to make data-oriented and effective decisions for this species conservation.

Unveiling the diversity of Giant Neotropical Torrent frogs (Hylodidae): phylogenetic relationships, morphology, and the description of two new species

The Neotropical family Hylodidae comprises 46 currently recognized rheophilic Torrent frog species, today classified in the genera Crossodactylus, Hylodes, Megaelosia, and Phantasmarana, all endemic to the Atlantic Forest. Megaelosia and Phantasmarana are distributed along the Serra do Mar and Serra da Mantiqueira mountain ranges, southeastern Brazil, and are the least speciose genera of the family, including all the mute giant hylodids. Megaelosia is a monotypic genus, whereas Phantasmarana comprises six currently recognized species: P. apuana, P. bocainensis, P. boticariana, P. jordanensis, P. lutzae, and P. massarti. Herein, we provide a taxonomic revision of these Giant Neotropical Torrent frogs, offering a comprehensively sampled species-level molecular phylogeny. By combining molecular and morphological data, we confirm that Megaelosia and Phantasmarana are valid genera. We provide diagnostic traits for both genera, redescribe the poorly known species P. jordanensis, and describe two new species from distinct localities at Parque Estadual da Serra do Mar, P. curucutuensis sp. nov. and P. tamuia sp. nov., presenting details of adult and larval morphology, and notes on their natural history and behaviour. We further discuss systematic and taxonomic concerns, and evolutionary processes related to distribution, body sizes, and communication in the family Hylodidae. http://zoobank.org/urn:lsid:zoobank.org:pub:61EA0116-6FB9-44B8-A2CE-E99D7B887E8B http://zoobank.org/urn:lsid:zoobank.org:act:079339E6-C802-4B47-A3A3-9FA0D0FCA3D1 http://zoobank.org/urn:lsid:zoobank.org:act:0EA22628-89E9-483B-AB90-F3F0D18E28F1

First record of Mirinaba cadeadensis (Gastropoda: Strophocheilidae) in an anthropogenic shell mound from the Paraná coast, Southern Brazil

Mirinaba cadeadensis Lange de Morretes, 1952 is restricted to the Paraná state, and found at the municipalities of Morretes, São José dos Pinhais, Paranaguá, Matinhos, and Guaratuba, associated to the Serra do Mar mountains. In this paper, we report the first record of this species in an anthropogenic shell mound. Two shells of M. cadeadensis were located in the internal stratigraphic layers of the Boguaçu shell mound. This is also the first shell mound record for Mirinaba.

Mangrove sediments as long-term mercury sinks: Evidence from millennial to decadal time scales

The mercury (Hg) cycle in estuaries has been globally discussed, although Holocene deposition in mangrove sediments remains unknown. Herein, a sediment core from a mangrove system in southeastern Brazil was 14C-dated to evaluate millennial Hg deposition. The highest Hg concentrations (1010–2540 ng g−1) in surface sediments were explained by emissions from a chlor-alkali industry (1964 CE). However, Hg levels were also high in pre-industrial periods, associated to fine grain-size and algal organic deposition. Less anomalous Hg concentrations in bottom sediments indicate Holocene ages (~1940–3324 cal yr BP), potentially associated to Serra do Mar mountains weathering. This study reveals the capacity of mangrove to retain Hg over millennial time scales, acting as significant and long-term Hg sinks. Therefore, the use of Hg as an Anthropocene marker must be considered cautiously in coastal systems that act as Hg sinks in times when environmental changes were not caused by human activities.

Notes on the Hyperossified Pumpkin Toadlets of the Genus Brachycephalus (Anura: Brachycephalidae) with the Description of a New Species

Four species of pumpkin toadlets are currently recognized by the extreme condition of hyperossification in the skull and vertebral column within the genus Brachycephalus. In addition to their larger body size, relative to other congeneric species, Brachycephalus darkside, Brachycephalus ephippium, Brachycephalus garbeanus, and Brachycephalus margaritatus share remarkable osteological features, such as the large paravertebral plates forming an ornamented dorsal bone shield, visible through the integument. We add to the current knowledge of this group by analyzing its diversity and describing a new hyperossified species from some important Atlantic Forest remnants in southeastern Brazil, including those bordering Sao Paulo, the largest and most populous city in South America. The new species is diagnosed by a combination of morphological, osteological, and bioacoustic characters, with further evidence of mtDNA sequences to confirm its distinction from the other congeners. The parotic and paravertebral bone plates externally bordered with a rough and pale contour can readily distinguish the new species from the other hyperossified species within Brachycephalus. The new species is widely distributed along the Serra do Mar mountain range, including the regionally named Serra de Paranapiacaba, in elevations from 700 to 1000 m above sea level (a.s.l.), in the central coast of the state of Sao Paulo, southeastern Brazil. We discuss valuable morphological characters within this group of species, reinforce the need for further studies, and highlight the relevance of protected areas for biodiversity conservation in metropolitan regions.

Paraphyly and evolutionary independent lineages in Gymnotus pantherinus (Gymnotiformes: Gymnotidae) in the Brazilian Atlantic Forest Coastal Streams

In the Brazilian Atlantic Forest (AF), many terrestrial species with broad geographical distributions show high diversity and endemism of intraspecific lineages, as revealed by molecular genetic data. This pattern, however, is less explored in freshwater fishes. Gymnotus pantherinus is an electric fish endemic to the Brazilian coastal drainages that shows a wide distribution, ranging from the states of Bahia to Santa Catarina, an unusual pattern for AF fishes. It has been hypothesized that G. pantherinus is a species complex because distinct morphotypes were described for the species based on morphometric and meristic features. We used mitochondrial and nuclear data to test this hypothesis. Based on phylogenetic inference and multi-locus, multispecies coalescent methods, we identified six independent lineages, flagging them as candidate species. One such lineage is the recently described species G. refugio that is nested within G. pantherinus and renders it paraphyletic, showing it is a species complex. We named G. pantherinus stricto sensu the lineage that includes samples from the type locality (Santos, SP). Our results show that genetic lineages correspond only partially and far exceed the number of previously reported morphotypes. Genetic breaks in the group correspond to landscape features associated with the Serra do Mar mountain range and with riverine dynamics caused by sea level changes during the last glacial maximum. Moreover, we found evidence of river capture events affecting phylogeographic structure in the group. We uncovered an important dimension of diversity in the group and encourage further integration of genetic and phenotypic data. Such integration is a fruitful approach not only to reduce the gap between taxonomy and evolutionary history in Gymnotidae, but also to uncover the real AF biodiversity.

Dragonflies (Insecta: Odonata) from Mananciais da Serra, a Tropical-Araucaria Forest ecotonal remnant in the southern Atlantic Forest, state of Paraná, Brazil

This study provides a comprehensive checklist of Odonata species from the protected area of Mananciais da Serra. The survey was conducted in the endangered Atlantic Forest domain at the southern Serra do Mar mountain chain within a well-preserved area in the municipality of Piraquara, state of Paraná, Brazil. Adults and larvae were sampled between June 2017 and March 2020 using different techniques in numerous mesohabitats, including phytotelmata, pools, small streams, and large reservoirs. A total of 1,708 specimens from 9 families, 43 genera and 84 species were sampled resulting in 53 new records for the state of Paraná, almost doubling the known occurrence records for dragonflies and damselflies in that state. Furthermore, two hitherto undescribed females from the generaPlaniplaxandHeteragrion, four ultimate stadium larvae fromPlaniplax,Neocordulia,Heteragrion, andAcanthagrion, and five undescribed species were detected, one each from the generaHeteragrion,Progomphus,Brechmorhoga,Erythrodiplax, andDasythemis. The estimated richness of odonates in this area is greater than 100 species, while the observed richness corresponding to almost 10% of all Odonata species in Brazil, the species-richest country in the world. These results reiterate the need to investigate undersampled areas to improve knowledge on diversity, taxonomy, and distribution of neotropical species. Finally, taxonomic notes for some species, including the rare corduliidNeocordulia mambucabensisCosta & T.C. Santos, 2000, are provided.