Southwestern Brazil Research Articles

Kapraunia silviae (Rhodomelaceae, Rhodophyta), a new species from the South Atlantic Ocean

Abstract Kapraunia is a genus recently segregated from Polysiphonia sensu lato, with only four species so far known. However, no species have been found on the South Atlantic coast. Recent collections in southwestern Brazil revealed specimens morphologically similar to Kapraunia spp. To investigate the identity of these specimens, we carried out a morphological and molecular study based on COI-5P and rbcL sequences. Phylogenetic analysis placed our samples within the genus Kapraunia as a new species with full support, described here as Kapraunia silviae sp. nov. K. silviae is recognizable by a combination of characters such as attachment by a basal disc and a prostrate system, branches developing laterally to the trichoblasts, 5–6 pericentral cells, rarely 4. The species differs from K. pentamera by the attachment form, segment proportions and tetrasporangial dimensions, and from K. schneideri by the number of pericentral cells, branch development and tetrasporangial arrangement. Re-examination of herbarium samples from Brazil in older collections also revealed misidentifications of K. silviae as “Carradoriella denudata”. This new species seems to be restricted to the Brazilian coast, being found only on the northern coast of São Paulo state. Our results reinforce the need for revision of Polysiphonia s.l. species on the Brazilian coast.

First predation event of an anuran by Holochilus chacarius in the Pantanal wetland, central portion of South America

Abstract The marsh rat (Holochilus chacarius) is considered a specialist herbivorous rodent. In this study, we report the first predation event of an anuran (Pseudis platensis) by a marsh rat in the Pantanal wetlands, South America. This unprecedent event in a flooded wetland in the municipality of Corumbá, Mato Grosso do Sul state, southwestern Brazil. Due to the flashlight, the rodent ceased its predatory activity and left, carrying the anuran in its mouth. Our findings contribute to the natural history of the marsh rat, highlighting that this herbivorous rodent can incorporate fresh animal matter into its diet.

First Assessment of a Pebble Tool Industry in the Pesqueiro River Valley, Upper Uruguay River Basin, Southern Brazil

Abstract This article presents the first findings of a topographic survey plotting the location of archaeological material and of a technological study of the lithic industry at the SC-CHA-030 open-air archaeological site along the Pesqueiro riverbank, located in the upper course of the Uruguay River Basin in southwestern Brazil. We analyzed raw material selection and the production of shaped/façonnage tools (unifacial, bifacial, and trihedral) associated with the production (debitage) of cortical and semi-cortical flakes that were then transformed into tools by simple retouch. From the geoarchaeological point of view, the spatial distribution pattern of the material is meaningful in the context of the geomorphic transition between foothills and alluvial plain. Our study of technological behavior and the formation of archaeological sites finds that raw material and shaped pebble tools are a crucial aspect of the industries on the Paraná Basaltic Plateau of southern Brazil.

The fish collection of Jos Mariano da Conceio Veloso (17421811) and the beginning of ichthyological research in Brazil, with a taxonomic description of the extant specimens.

Two Portuguese institutions, the Museu Maynense da Academia das Cincias de Lisboa (ACL), and the Museu da Cincia da Universidade de Coimbra (MCUC), house a collection of 85 dried fish specimens prepared in what can be called a fish-herbaria following a process similar to that developed by the Dutch naturalist Johan Frederic Gronovius (16901762). These specimens date back to the late eighteenth century and represent Brazilian taxa. Previous authors assumed that they were part of the collections amassed by the Brazilian-Portuguese naturalist Alexandre Rodrigues Ferreira (17561815) during his philosophical voyage to the Amazon. Here we present a review of these specimens, suggesting that they belonged to Friar Jos Mariano da Conceio Veloso (17421811) and describe the history of dispersal of these collections up the present day. A total of 58 species in 50 genera, 32 families and 19 orders are represented in the collection. Only 8.6% of these specimens represent freshwater species, while 91.4% are marine or brackish water species. The present known distribution of these taxa is focused on southwestern Brazil, which agrees with the area where Veloso collected natural history specimens. A good percentage of the species were undescribed at the time Veloso collected them, and had they been published by him, would have had priority over species described decades later by famous eighteenth and nineteenth century ichthyologists. We also present a brief discussion on the challenges and opportunities of studying historical natural history specimens, with special focus on those amassed during the late eighteenth and early nineteenth century by Brazilian-Portuguese naturalists.

Assessing carbon sequestration in a high-diversity restoration plantation in the Atlantic Forest of southwestern Brazil

Assessing carbon sequestration in a high-diversity restoration plantation in the Atlantic Forest of southwestern Brazil

Predation of Atelocynus microtis and Speothos venaticus (Carnivora: Canidae) by Boa constrictor (Squamata: Boidae) in Southwestern Brazil and Southeastern Peru

Literature on the predation ecology of Amazonian canids is scarce, especially for the two rarely observed canids; Speothos venaticus (Bush Dog) and Atelocynus microtis (Short-eared Dog). Between 2000 and 2005 we documented one observation of predation of a A. microtis from southeastern Peru and an observation of S. venaticus predation from southwestern Brazil.

Effects of forest loss and fragmentation on bat-ectoparasite interactions

Human land use causes habitat loss and fragmentation, influencing host-parasite associations through changes in infestation rates, host mortality and possibly local extinction. Bat-ectoparasite interactions are an important host-parasite model possibly affected by such changes, as this system acts as both reservoirs and vectors of several pathogens that can infect different wild and domestic species. This study aimed to assess how the prevalence and abundance of bat ectoparasites respond to forest loss, fragmentation, and edge length. Bats and ectoparasites were sampled at twenty sites, forming a gradient of forest cover, in southwestern Brazil during two wet (2015 and 2016) and two dry (2016 and 2017) seasons. Effects of landscape metrics on host abundance as well as parasite prevalence and abundance were assessed through structural equation models. Nine host-parasite associations provided sufficient data for analyses, including one tick and eight flies on four bat species. Forest cover positively influenced the prevalence or abundance of three fly species, but negatively influenced one fly and the tick species. Prevalence or abundance responded positively to edge length for three fly species, and negatively for the tick. In turn, number of fragments influenced the prevalence or abundance of four fly species, two positively and two negatively. Our results support species-specific responses of ectoparasites to landscape features, and a tendency of host-generalist ticks to benefit from deforestation while most host-specialist flies are disadvantaged. Differences in host traits and abundance, along with parasite life cycles and environmental conditions, are possible explanations to our findings.

Two new land planarian species (Platyhelminthes: Tricladida) from the Cerrado biome in southwestern Brazil

Most Neotropical land flatworm species are known from areas of the Atlantic Forest. Herein, we describe two new land planarian species from areas of semideciduous forest in the Cerrado biome in southwestern Brazil. Paraba aurantia Marques & Leal-Zanchet, sp. nov. can be distinguished from its congeners by the wide black median band on the dorsum, eyes occupying almost the entire dorsal surface, prostatic vesicle twisted and asymmetrical with proximal portions forked, and female atrium with an ample lumen lined by a low epithelium with stratified appearance. Pasipha liviae Marques & Leal-Zanchet, sp. nov. shows a narrow longitudinal dorsal stripe, collar-shaped pharynx, and prostatic vesicle with a pear-shaped proximal portion and a globose distal portion separated by a constriction. In addition, P. liviae can be distinguished from its congeners by molecular analyses from the cytochrome c oxidase subunit I gene (COI). Phylogenetic analyses suggest that P. liviae is closely related to P. hauseri, which occurs in areas of semidseciduous forest in southern Brazil.

Four new species of Hecabolus Curtis, 1834 (Braconidae, Doryctinae) from south and southwestern Brazil, with notes on the morphological variation and geographic distribution of H. mexicanus Zaldívar-Riverón & Belokobylskij, 2009

Four new species of the braconid wasp genus Hecabolus Curtis, 1834 (Doryctinae Foerster, 1863) are described for the Neotropical region in south and southwestern Brazil: H. acutus sp. nov., H. chrisaxeli sp. nov., H. gavinbroadi sp. nov., and H. transversalis sp. nov. We also report the morphological variation of females and males of H. mexicanus Zaldívar-Riverón & Belokobylskij, 2009, originally described based on a single female, and provide its first precise geographical distribution records. An updated key to the 13 described species of Hecabolus is provided.

Occurrence of the Sylvatic Yellow Fever Vector Mosquito Haemagogus leucocelaenus (Diptera: Culicidae) in an Atlantic Forest Fragment of the Touristic State of Rio de Janeiro, Brazil.

The yellow fever virus is estimated to cause 30,000 deaths each year worldwide, with the majority of cases and deaths occurring in Africa. The virus is also endemic to Central and South America, including northern and western Brazil. The sylvatic cycle of the virus is related to wild and rural areas, with nonhuman primates as the primary host and wild mosquitoes, specifically from the genera Haemagogus, as vectors. The diversity of the mosquito community plays a significant role in the increase of pathogen transmission to humans. In the present study, we detected fluctuation in populations of vector mosquitoes using ovitraps for Culicidae egg collection. The study area is a forest fragment of the Atlantic Forest, one of the most threatened biomes in Brazil. This biome has been suffering significant deforestation due to anthropic activity. Worryingly, the proximity of human populations to forest environments increases the risk of spreading disease from forest fragments to urban areas. Our findings showed that the highest egg abundance occurred in December 2019, with a significant difference (p = 0.005) between rainy and dry seasons. Most eggs were collected during the rainy period. Subsequent quantification of specimens from epidemiologically relevant species hatched from field-collected eggs resulted in 1,131 (86%) Haemagogus leucocelaenus (Dyar & Shannon, 1924), 111 (8%) Aedes terrens (Walker, 1856), 47 (4%) Aedes albopictus (Skuse, 1894), and 21 (2%) Haemagogus janthinomys (Dyar, 1921). Finally, we assessed the behavior of different vector species performing oviposition on the same breeding site. The highest correlation coefficient was observed between Ae. albopictus and Ae. terrens (rho = 0.52) concerning other Culicidae species. Therefore, we believe that Culicidae population surveillance is crucial for disease monitoring since the increase in specimens of a number of vector species influences the emergence of yellow fever cases in nonhuman primates and human populations.

Detrital zircon U-Pb provenance analysis of Precambrian and Paleozoic strata from southwestern Brazil: Assessment of potential Grenvillian sediment input and Amazonian-Laurentian tectonic interaction

Southwest Amazonia is proposed to have collided with southeast Laurentia during the Grenville orogeny. In Laurentia, the collision produced a continental-scale late Mesoproterozoic to early Neoproterozoic clastic wedge dominated by detrital zircon (DZ) sourced from Grenvillian magmatic rocks (major Geon 11 and 10, with minor Geon 13, 12, and 9 ages: the “Great Grenvillian Sedimentation Episode”). New DZ ages in clastic units from southwestern Brazil permit testing the hypothesis that Grenvillian sediment from southeast Laurentia spilled onto western Amazonia during Rodinian assembly. Late Mesoproterozoic arenites are dominated by Geons 18, 17, 15, 14, and 13 ages sourced from Amazonia basement provinces. Two samples exhibit major Geon 12 and 11 ages with minor Geon 18–13 ages. Geon 12 and 11 correspond to a conspicuous age gap in Amazonian magmatic events. Latest Neoproterozoic samples exhibit minor Geon 13 to 9 ages interpreted to be sourced from the Rondônia-San Ignacio or Sunsás provinces of western Amazonia. Late Neoproterozoic and Devonian age spectra exhibit multiple Amazonian age modes ∼2500 to 500 Ma but with no dominant modes. The age distributions for all samples indicate a lack of Laurentian Grenville sediment influx to southwest Amazonia during Rodinian assembly and breakup. The enigmatic Geon 12 ages are interpreted to correspond to a buried Andean source or the southwestern Grenville province in Laurentia. In contrast to exposed basement in southwestern Amazonia, Andean basement clastic sequences and Pleistocene to Recent Amazon River sediments exhibit Grenville dominance of DZ ages, strikingly similar to eastern Laurentia clastic systems. The Andean Grenville dominance may be accounted for by extensive Grenvillian crust beneath the Andean clastic wedge containing a major component of Geons 12, 11 and 10 magmatic rocks, and which was not being fully exhumed until the Neoproterozoic, similar to Laurentian Grenville.

The New Standpoints for the Terroir of Coffea canephora from Southwestern Brazil: Edaphic and Sensorial Perspective

The sensory profile from the Coffea canephora stands out for being denser, less sweet, presenting less acidity, and having characteristics of a marked aroma of roasted cereals. Coffee is essentially a terroir product, that is, directly influenced by environmental aspects, both natural and anthropic, in this sense, it has been argued that Coffea canephora is linked to the context of inferior coffees in sensory terms by the terroir conditions. This study aimed to characterize and investigate the terroir in different areas of Conilon coffee production, with the application of different fermentation methods, and to observe their possible gains and losses in the sensory quality of Coffea canephora. Cherry coffee samples were collected in six municipalities in the state of Espírito Santo, Brazil, which has an altitude variation from 376 m to 866 m. The study showed that the local characteristics of altitude and temperature directly influence the sensory quality, as well as demonstrated that natural fermentation in a specific altitude zone delivered good results, fixing the terroir factor. Finally, it was demonstrated that induced fermentation helps to improve sensory quality for higher altitude areas, indicating the possibility of reformulating the terroir of Conilon coffee production.

New Facies Model and Carbon Isotope Stratigraphy for an Ediacaran Carbonate Platform From South America (Tamengo Formation—Corumbá Group, SW Brazil)

The Ediacaran is a period characterized by the diversification of early animals and extensive neritic carbonate deposits. These deposits are still not well understood in terms of facies and carbon isotope composition (δ13C). In this study we focus on the Tamengo Formation, in southwestern Brazil, which constitutes one of the most continuous and well-preserved sedimentary record of the late Ediacaran in South America. We present new detailed lithofacies and stable isotopes data from two representative sections (Corcal and Laginha) and revise the paleoenvironmental and stratigraphic interpretation of the Tamengo Formation. The Corcal section consists of neritic deposits including shallow-water limestone beds, alternated with shale and subordinate marl beds. These facies yield specimens of the Ediacaran fossils Cloudina lucianoi and Corumbella werneri. On the other hand, the Laginha section shows more heterogeneous facies, such as impure carbonates, breccias, marls, and subordinate mudstone beds, as well as no evidence of Corumbella werneri. The stable carbon isotope record is also different between the two sections, despite belonging to the same unit. The Corcal section displays higher and more homogeneous δ13C values, consistent with those of Ediacaran successions worldwide. The Laginha section, instead, displays more variable δ13C values, which suggest the influence of local and post depositional processes. The difference between the two sections was attributed to the different distance from the shore. We propose that the difference is due to topographic variations of the continental platform, which, at the Laginha site, was steeper and controlled by extensional faults. Therefore, the Corcal section is a better reference for the Tamengo Formation, whereas the Laginha is more particular and influenced by local factors. Besides, the lithofacies associations of the Tamengo Formation are like those of the Doushantuo and Dengying formatios, in South China, with no significant biogenic carbonate buildups, and different from those of other important Ediacaran units, such as the Nama Group in Nmibia and the Buah Formation in Oman. Our work highlights the complexity and heterogeneity of Ediacaran carbonate platforms and of their carbon isotopic composition. In addition, we characterize the Corcal section as a possible reference for the Ediacaran in South America.

Taxonomy, distribution, and conservation status of <i>Geonoma</i> (Arecaceae, Arecoideae): new records for the Maranhão state, Brazil

Geonoma is one of the more diverse genera of palms in the neotropical region, which comprises 68 species distributed from southern Mexico to south-western Brazil. In Maranhão, a Brazilian state located in a transition area between the Eastern Amazon, the Cerrado, and the Caatinga, the knowledge about this genus still is deficient. For this reason, we elaborated a taxonomic study of the genus Geonoma for the state, based on the descriptive analysis of voucher specimens of national and international herbaria, and specimens collected in our expeditions. A total of five species were identified: G. baculifera and G. leptospadix species were previously cited in the literature, whereas G. maxima subsp. maxima, G. pohliana subsp. weddelliana and G. poiteauana are presented as new records. Taxonomic descriptions and distribution information are shared, as well as preliminary conservation status assessments of these species. Moreover, an identification key for all species in the state is also supplied. These findings extend the distribution and conservation knowledge of some Geonoma species, and are an important contribution to the identification of the taxa in the region.

Redescription of Rhinus ciliatus (Gastropoda: Simpulopsidae), An Endemic Species from the Atlantic Rainforest in Brazil

The genus Rhinus Martens, 1860, is represented in Brazil by about twenty species, which are predominantly found in the Atlantic rainforest, an endangered ecosystem with extraordinary biodiversity and high endemism. There is a dearth of detailed morphological data for most species of the genus Rhinus, and the anatomy of only a few species has been described. Rhinus ciliatus, an endemic species from southwestern Brazil, is known by few conchological traits and scarce anatomical data from the reproductive system and pallial cavity. In this study, we redescribe the shell morphology and soft body anatomy of Rhinus ciliatus in detail and compare the new data with known traits of other closely related species. Rhinus ciliatus is diagnosed by the following features: (i) transition from protoconch to teleoconch well marked; (ii) shell ovate-conic, accuminate; (iii) aperture sub-ovate, lip simple; (iv) kidney with granulated lamellae; and (v) marginal teeth with blunt spatula-shaped mesocones. The record of spermatophores for the genus is provided here for the first time.

A Permian mixohaline ostracod association of the Teresina Formation, Paraná Basin, Brazil

New ostracod species are described for Middle to Upper Permian (Guadalupian) rocks of the Teresina Formation, Paraná Basin, from two localities in the São Paulo State, southwestern Brazil: Xavante Dam and Pau Preto Quarry. Paranacythere nigripallus gen. nov. and sp. nov., Velatomorpha xavante sp. nov., and Velatomorpha pseudoaltilis sp. nov. are herein described. The association Velatomorpha–Paranacythere is proposed as typical of Permian mixohaline environments of the Teresina Formation, and is the most abundant in the two studied localities. Paranacythere nigripallus gen. nov. and sp. nov. is proposed to accommodate a very abundant species with typically cytheroidean characteristics, and tentatively ascribed to the family Cytheruridae. Some ecological remarks are presented based on ostracod population age structure, biostratinomy and taxonomic composition of assemblages. The diagnosis of Velatomorpha Tibert & Dewey is emended. Keywords: evolution, marginal marine environments, paleoecology, Teresina Formation, taxonomy.

Atlantic Forest birds are more functionally and taxonomically diverse in valley bottoms relative to uplands

The theory behind metacommunity was recently reframed to incorporate the concepts of community ecology. Here we investigate how slight topographic variations might locally create habitat heterogeneity and a system of interchanging bird species (i.e., a metacommunity) in a continuous tropical forest. We studied the distribution of birds in a large and protected Neotropical Forest in southwestern Brazil to understand the influence of valley bottom sites on the taxonomic and functional diversity of the bird communities. As previous studies have shown that specialist species have spatially regular distribution when compared to generalists, in the present study we investigate if topography could influence those local patterns of distribution. We expected (1) to find higher taxonomic and functional diversity in communities of valley bottom areas and (2) lower beta taxonomic and functional diversity of the generalists at the valley bottom, but not of specialists, that should exhibit a somewhat consistent distribution. We gathered information on the composition of local bird communities by deploying eight automatic recording units, four in the valley bottoms and four in the uplands, along 4.3 km trail in the forest interior. Our data showed that bird diversity at the valley bottoms tended to be higher than that at the uplands. Specialist passerine assemblages presented high spatial stability and were regularly distributed throughout the forest. In contrast, generalist passerines have limited trait distribution due to valley bottoms. Because bird communities were distinct from each other, deforestation should have stronger impact in the system if only upland areas are left in the landscape. In this case, species dispersal and coexistence as well as complementary traits have predicted implications for the remaining forest fragments, and management actions should prioritize the conservation of forest fragments that include both bottom valleys and uplands areas.

Regionalization of water quality parameters based on the landscape characteristics of small ungauged basins: a study carried out in south-eastern Brazil

One of the main problems associated with the analysis of water quality parameters (WQPs) in developing countries is the low number of sampling sites in small watersheds. One of the strategies used to solve this problem involves estimating WQPs based on the extrapolation of measurements carried out in other basins using regionalization methods associated with landscape characteristics. The objectives of this study were to evaluate the associations between landscape characteristics and WQPs and to propose a methodology for the regionalization of WQPs based on landscape characteristic data obtained from basins where WQP data were sampled. The study area was the upper Piracicaba-Jaguari River basin located in south-western Brazil. The methodology was based on a survey of 27 environmental variables and 12 water quality parameters in 44 small sub-basins. The non-parametric k-nearest neighbour regression (K-NNR) algorithm was used to estimate the WQP values for the small sub-basins that lacked data. The results showed that the landscape characteristics of the studied sub-basins related to land use and cover significantly influenced the WQPs. The mapped regions showed significant differences among the total dissolved solids, chloride, electric conductivity, pH, salinity, resistivity, dissolved oxygen, and nitrate parameter values.

Alien corals in a Brazilian seaport and perspectives for improving marine bioinvasion detection and management in commercial ports

Two invasive coral species, Tubastraea coccinea and T. tagusensis, were identified on underwater artificial structures during a routine inspection at the Port of São Sebastião in southwestern Brazil in 2019. Both species were previously recorded in natural and artificial substrata in the region since 2008, including marine protected areas, but never found in the Port area. Tubastraea spp. are highly invasive species that outcompete native and endemic species, trigger seascapes changes, and modify ecosystem functions. Although it is uncertain if the São Sebastião Port was the primary source of these bioinvasion, ports' activity might enhance secondary dispersion, collaborating to spread the invasive species. This finding triggered a request by the Brazilian Institute of Environment (IBAMA) to the implementation of a specific plan to control the Tubastraea invasion attached to the invasive species monitoring program, which was one of the conditions to renew the operation license of the São Sebastião Port in 2020. Here, we recommend that commercial seaports consider including biota monitoring programs focusing on detecting marine non-indigenous species. Furthermore, we provided some subjects that should be incorporated in monitoring programs and highlight the need for evaluation of underwater artificial structures additionally to adjacent rocky shores. If a potentially invasive species is detected, a specific plan to control the invaders should be developed, as well as strategies to control invasive species dispersion. The monitoring program should be planned under the guidance of environmental agencies and incorporate the scientific community and general society, stimulating partnerships and discussions focusing on better understanding biological invasions in seaports and improving their management.

Geomorphological imprint of opposing ocean bottom currents, a case study from the southeastern Brazilian Atlantic margin

The combination of oceanographic processes and a negligible fluvial terrestrial sediment contribution makes the Santos Basin margin (southwestern Brazil) a unique environment for studying thew morphological imprint of bottom currents on the seafloor morphology. We divide the seafloor into four domains: outer shelf, upper, middle, and lower slope, based on an analysis of sub-bottom Chirp profiles, multichannel seismic data, hydrographic data, numerical simulation outputs, and a seismic-derived bathymetry map. A clinoform at the outer shelf and upper slope, topped by erosional morphologies, developed below the SW-flowing Brazil Current (BC). At the bottom of the upper slope, a rugged and mounded surface around 600 mbsl coincides with the current flow reversal to the underlying NE-flowing Intermediate Western Boundary Current (IWBC). The smooth middle slope exhibits sheeted contourites interrupted by occasional channel-and-mound complexes.From the middle slope base, salt tectonics becomes a major player in setting the seafloor morphology. The slope-parallel Santos Channel develops above a subsurface diapir and the Cabo Frio Fault. The latter divides between the landward gap in subsurface Albian salt and the basinward rich diapir realm. Hence, the lower slope is reworked by the SW-flowing Deep Western Boundary Current (DWBC); however, salt tectonics dictates its morphology. Our study consists of a unique example for studying the morpho-sedimentary imprint of a counter-current flowing on the continental slope and also for exploring the interaction between bottom flows with a suite of endogenic processes, such as salt tectonics, fluid flows, and mass movements.