Adolpho Ducke Research Articles

Cryptic insect soundscapes: Ecological sound art as a prompt for auralization

Much insect sounding is beyond the limits of typical human hearing ability. This sonic separation is exacerbated by a socialized narrative of fear and avoidance of insects in many western societies. With the use of audio technologies to expand our senses, we can embrace opportunities to get to know sensory and communicative insect sound-worlds beyond our own. Ecological sound art – sound art that has an environmentalist intent – is a tangible and accessible means of listening to these sounds. In the series Built Hidden Soundscapes, the primary author (Schonberg) composes imagined soundscapes existing solely of sounds that are beyond the limits of typical human hearing ability. In this article we introduce two compositions in this series, Reserva Florestal Adolpho Ducke and Pipeline Road. These compositions offer a temporary expansion of our aural senses that can increase listeners’ awareness of cryptic insect existences/ecologies. We suggest that this listening practice might prompt future auralization (sounding or hearing in the mind) of insect sound for the listener.

Heterospecific pollen deposition in understory plants of a forest in central Amazon

In co-flowering plant communities, pollinator movement can lead to the transfer of heterospecific pollen among species. This can affect the reproductive success of individuals, either by preventing conspecific pollen from reaching the stigma or by allelopathy, but little is known about this process in tropical areas. To analyze heterospecific pollen transfer and deposition, we investigated attributes related to pollinator attraction, such as corolla size, number of flowers per individual, floral arrangement, floral asymmetry, and distance from one flowering individual to another in a Central Amazon forest. The study was carried out in riparian plots of the Adolpho Ducke Forest Reserve during the rainy season. Stigmas and anthers were removed from all individual understory plants found in bloom in permanent plots. Slides were mounted with glycerinated gelatin, and all conspecific and heterospecific pollen grains were identified and counted. We then used a generalized linear mixed model framework to determine how the measured variables were related to the proportion of heterospecific pollen deposition (HPD) on stigmas. We found that the mean proportion of HPD in individuals was 4.7%, and 60% of individuals had no heterospecific pollen; from the 14 species studied, two had no heterospecific pollen. Species with wider flowers received less HPD, while species with more flowers per individual and with solitary flowers received more heterospecific pollen. Despite the significant variation in floral types in the Adolpho Ducke Reserve, there was a low percentage of heterospecific pollen deposition, probably due to specialized plant-pollinator interactions.

Correlation between caffeine and coprostanol in contrasting Amazonian water bodies

The evaluation of contamination by domestic sewage is relevant in the Amazon region; however, it has neither been well-developed nor accompanied by research or monitoring programs. In this study, caffeine and coprostanol as indicators of sewage were investigated in water samples from Amazonian water bodies that crisscross the city of Manaus (Amazonas state, Brazil) and cover regions with distinct main land uses such as high-density residential, low-density residential, commercial, industrial, and environmental protection areas. Thirty-one water samples were studied based on their dissolved and particulate organic matter (DOM and POM) fractions. Quantitative determination of both caffeine and coprostanol was carried out using LC-MS/MS with APCI in the positive ionization mode. The streams of the urban area of Manaus had the highest concentrations of caffeine (1.47–69.65 μg L−1) and coprostanol (2.88–46.92 μg L−1). Samples from the peri-urban Tarumã-Açu stream and from the streams in the Adolpho Ducke Forest Reserve showed much lower concentrations of caffeine (20.20–165.78 ng L−1) and coprostanol (31.49–120.44 ng L−1). Samples from the Negro River showed a wider range of concentrations of caffeine (20.59–873.59 ng L−1) and coprostanol (31.72–706.46 ng L−1), with the highest values found in the outfalls of the urban streams. Levels of caffeine and coprostanol were significantly positively correlated in the different organic matter fractions. The coprostanol/(coprostanol + cholestanol) ratio proved to be a more suitable parameter than the coprostanol/cholesterol one in low-density residential areas. Proximity to densely populated areas and the flow of water bodies appear to influence the caffeine and coprostanol concentrations, which was observed in their clustering in the multivariate analysis. The results indicate that caffeine and coprostanol can be detected even in water bodies that receive very low domestic sewage input. Therefore, this study revealed that both caffeine in DOM and coprostanol in POM represent viable alternatives for use in studies and monitoring programs even in remote areas of the Amazon, where microbiological analyses are often unfeasible.

THE SPETACLED CAIMAN (Caiman crocodilus, CROCODYLIA, ALLIGATORIDAE) AS A PREDATOR OF THE AMAZON SAILFIN-CATFISH (Pterygoplichthys pardalis, SILURIFORMES, LORICARIDAE)

We report an event of a Caiman crocodilus consuming the catfish Pterygoplichthys pardalis. A list of known prey items of C. crocodilus was also compiled from the literature, including known vertebrate and invertebrate items for this species. The predation event was observed at the margin of a lagoon in Reserva Florestal Adolpho Ducke, located in the municipality of Manaus, Amazonas state, Brazil, during a fieldwork study in 2020. The literature survey revealed 250 distinct prey items for this caiman, of which 150 are invertebrates (89 Insecta, 24 Crustacea, 14 Mollusca,10 Arachnida, 10 Myriapoda, 2 Annelida, and 1 Platyhelminthes) and 100 are vertebrates (53 fishes, 16 reptiles, 11 amphibians, 10 birds, and 10 mammals). Among fishes, only three Siluriformes have been taxonomically identified as C. crocodilus preys: Hoplosternum littorale, Clarias batrachus, and Ameiurus nebulosus. Therefore, the catfish P. pardalis represents a new prey specie for C. crocodilus. Our field observation and the presented literature review reinforce the view of C. crocodilus as a generalist predator, with fish as the most important vertebrate prey in the diet of this species.

Soldadinhos (Hemiptera, Auchenorrhyncha: Aetalionidae e Membracidae) do extremo oeste do Acre, Brasil, com ênfase na fauna do Parque Nacional Serra do Divisor

Abstract The first list of Aetalionidae and Membracidae species for western Acre is presented, including the Alto do Juruá regions of Serra do Divisor National Park and the Campus Floresta of the Federal University of Acre. In total, 94 species of treehoppers were collected, of which Centrotinae (Membracidae) is recorded for the first time for Brazil (Abelus maculatus Schimidt), another 16 species are new Brazilian records, and 69 species (Aetalionidae and Membracidae) are new records for Acre. Data on type locality, geographic distribution and images of all species are presented. The males of Lophyraspis fenestrata Sakakibara & Creão-Duarte and Erechtia sanguinolenta (Fairmaire) are known for the first time. The species diversity was compared to four other treehopper surveys in the Amazon region, with similarity indices of about 43.6% for Colombian Amazon (at least 650 km away), 27.6% for Panguana Biological Research Station, Peru (250 km), 20.2% for Adolpho Ducke Forest Reserve, Brazil (1,600 km) and 8.5% for Villa Carmen Biological Station/Los Amigos Biological Station, Peru (600/700 km). The estimated richness of Serra do Divisor National Park was just over 70%, suggesting that local diversity could be significantly higher than that presented in this study.

Essential oils, chemical stimulation of resin and occurrence of galls in three Amazonian species of Protium

Protium is the most frequent genus of Burseraceae in the Adolpho Ducke Forest Reserve (Manaus, Amazonas), which is where its species were previously identified and mapped and this has favored various studies of this central Amazon forest. A number of P. divaricatum Engl., P. opacum Swart and P. strumosum Daly trees were selected with the objective of providing information about their chemical and biological aspects. Resin exudation was stimulated with the use of ethephon and the essential oils from the aerial parts and the resin were evaluated using GC. The occurrence of galls was also registered. The hydrocarbon sesquiterpene ß-caryophyllene was detected in high percentages in the essential oils of leaves and twigs of P. divaricatum (52.75% and 14.74%) and P. opacum (39.55% and 17.86%), respectively. The predominant oxygenated sesquiterpenes were spathulenol in the leaves (19.52%) and twigs (31.29%) of P. divaricatum, in addition to khusimone (32.36%) in the twigs of P. opacum. Monoterpenes were identified in the essential oils of the P. strumosum resin, with p-cymene (58.97%) predominating in the naturally exuded resin, limonene (61.45%) and p-cimen-8-ol (53.92%) in the resin of the first and second extraction with ethephon, respectively. On the trees, galls were identified that will help in the identification of the three species.

Characterization of essential oils from odoriferous resins of Amazonian species of Protium Burm. f.

The odoriferous resins produced by the trees of Protium spp (Burseraceae) are known in the Amazonian region as “breus” where they have been used to caulk canoes, as a mosquito repellent, and also have potential use in perfumery. Most species in this region have had the essential oils of their resins characterized, thus, the objective of this study was to evaluate for the first time the volatile constituents from the resin of Protium gallosum Daly, P. paniculatum Engl., P. pillosum (Cuatrec.) Daly and P. paniculatum var. riedelianum (Engl.) Daly. The samples from the individuals that had been previously identified were collected at the Adolpho Ducke Forest Reserve and subjected to hydrodistillation in a Clevenger apparatus, and the essential oils obtained were analyzed using GC-FID and GC-MS. The essential oil of P. gallosum showed high percentages of oxygenated monoterpenes (43.61%) with a predominance of terpin-4-ol (25.15%), and P. paniculatum consisted exclusively of monoterpenes that were predominantly p-cymene (43.52%; hydrocarbon monoterpene) and the 1,8-cineole (16.83%; oxygenated monoterpene). Most of the monoterpenes identified from P. pillosum and P. paniculatum var. riedelianum were hydrocarbons with a predominance of α-pinene, with 37.74% and 50.93%, respectively. 1,8-Cineole (21.89%) was also identified in the essential oil of P. pillosum. The results obtained this study add chemical knowledge to Burseraceae resins from a biological reserve of the Central Amazon.

Óleos essenciais das partes aéreas de quatro espécies of Protium (Burseraceae) – Uma contribuição para a flora aromática da Reserva Florestal Adolpho Ducke, Amazonas, Brasil

The Adolpho Ducke Forest Reserve is a fragment of the Amazon Rainforest that has the highest density of collections deposited in the INPA herbarium, and this characterized, vascular flora has been an important basis for chemical studies. This paper describes the chemical composition of the volatiles of aerial parts of the four species of Protium that occurr in the Ducke Reserve. The essential oils obtained by hydrodistillation were analyzed using GC-FID and GC-MS. P. altsonii showed high percentages of the monoterpenes α-pinene (22.05%) and limonene (17.76%) in the leaves, and linear long-chain fatty alcohols, such as n-tetradecanol (19.93%) and hexadecanol (32.56%), in the branches. The essential oil from leaves of P. laxiflorum provided sesquiterpenes α-copaene (18.98%), epi-α-cadinol (9.17%) and β-caryophyllene (9.04%) as the main compounds. In P. pallidum, the sesquiterpenes caryophyllene oxide (29.72%), α-cadinol (28.82%) and epi-α-cadinol (13.96%) were predominant in the leaves, and α-cadinol (25.50%), α-eudesmol (22.29%) and caryophyllene oxide (12.81%) predominated in the branches. β-Caryophyllene (30.59%) and caryophyllene oxide (20.63%) were the main compounds in the leaves of P. paniculatum var. riedelianum. The results presented herein contribute to the knowledge of the aromatic flora of the Ducke Reserve.

Breeding ecology of Rufous Potoo Nyctibius bracteatus in central Amazonian Brazil

The smallest potoo, Rufous Potoo Nyctibius bracteatus is a little-known and inconspicuous species of the understorey in Amazonian terra firme forests, where it roosts by day. Currently, there are few published observations describing its natural history and reproductive ecology. We present data on nest and egg characteristics, nestling appearance, behaviour and development, and parental care, based on three different nests in three consecutive years at Reserva Florestal Adolpho Ducke, Manaus, central Amazonian Brazil. All nests had similar characteristics and the single egg at one nest was cream-coloured with brown spots. The young at one nest fledged when c.40 days old, but the other two nests were both predated by ant swarms, constituting the first report of such predation in the Nyctibiidae.

Evaluation of volatile constituents, exudation of resin and occurrence of galls of Protium aracouchini (Aubl.) Marchand

Protium aracouchini (Aubl.) Marchand [sin Icica aracouchini Aubl.], which occurs in the Adolpho Ducke Forest Reserve, in the Brazilian Amazon, was evaluated for the presence of galls, for resin exudation and the composition of the essential oils from the aerial parts and the resin. The experiment to stimulate the exudation of resin from the trunk was conducted using a 2-chloroethylphosphonic acid solution. The resin produced after 40 days and the aerial parts had their essential oils extracted in a Clevenger apparatus and the volatile chemical constituents were analyzed using GC/MS. The non-oxygenated sesquiterpenes α-copaene (21.15%) and α-gurjunene (13.69%), in addition to the oxygenated sesquiterpene spathulenol (10.32%), were detected as the majority constituents of the essential oil of the leaves, and a concentration similar to that of α-gurjunene was found in the branches (13.28%). The resin essential oil showed a high concentration of hydrocarbon monoterpenes (76.49%) with a predominance of α-pinene (17.57%) and limonene (46.11%). Four gall morphotypes were found associated with this species. The present study reports for the first time information on the volatile constituents and the resinous potential of P. aracouchini, and registers the morphotypes of the galls that help in the taxonomy of the species.

Synopsis of Lestes from Brazil with description of Lestes demarcoi sp. nov. (Zygoptera: Lestidae).

The Brazilian fauna of Lestidae contains two genera (Archilestes Selys, 1862 and Lestes Leach in Brewster, 1815) with 14 species, many of which are poorly defined and/or known only by primary literature. To improve the knowledge of the Brazilian species of the genus Lestes we examined 97 specimens pertaining to 11 of the 13 described species. Additionally, a new species is described here in honor to Prof. Dr. Paulo De Marco Júnior: Lestes demarcoi (Holotype and Allotype: Brazil: Amazonas, Manaus, Reserva Adolpho Ducke, Acará trail, 02º55'46" S 59º58'22" W, 62 m, 13.iv.2009, collected in tandem, U.G. Neiss leg. and deposited in FAAL). Diagnostic illustrations of all species are provided. Color photographs of live individuals of Lestes dichrostigma Calvert, 1909, Lestes forficula Rambur, 1842 and Lestes paulistus Calvert, 1909 are also presented.

EDNA in a bottleneck: Obstacles to fish metabarcoding studies in megadiverse freshwater systems

AbstractThe current capacity of environmental DNA (eDNA) to provide accurate insights into the biodiversity of megadiverse regions (e.g., the Neotropics) requires further evaluation to ensure its reliability for long‐term monitoring. In this study, we first evaluated the taxonomic resolution capabilities of a short fragment from the 12S rRNA gene widely used in fish eDNA metabarcoding studies, and then compared eDNA metabarcoding data from water samples with traditional sampling using nets. For the taxonomic discriminatory power analysis, we used a specifically curated reference dataset consisting of 373 sequences from 258 neotropical fish species (including 47 newly generated sequences) to perform a genetic distance‐based analysis of the amplicons targeted by the MiFish primer set. We obtained an optimum delimitation threshold value of 0.5% due to lowest cumulative errors. The barcoding gap analysis revealed only a 51.55% success rate in species recovery (133/258), highlighting a poor taxonomic resolution from the targeted amplicon. To evaluate the empirical performance of this amplicon for biomonitoring, we assessed fish biodiversity using eDNA metabarcoding from water samples collected from the Amazon (Adolpho Ducke Forest Reserve and two additional locations outside the Reserve). From a total of 84 identified Molecular Operational Taxonomic Units (MOTUs), only four could be assigned to species level using a fixed threshold. Measures of α‐diversity analyses within the Reserve showed similar patterns in each site between the number of MOTUs (eDNA dataset) and species (netting data) found. However, β‐diversity revealed contrasting patterns between the methods. We therefore suggest that a new approach is needed, underpinned by sound taxonomic knowledge, and a more thorough evaluation of better molecular identification procedures such as multi‐marker metabarcoding approaches and tailor‐made (i.e., order‐specific) taxonomic delimitation thresholds.

A Neglected New Species of Hymenaea (Leguminosae, Detarioideae) fromthe Brazilian Amazon

Abstract—A new species, Hymenaea jeaniana, is described and illustrated. The species is known from one of the best-sampled reserves of Amazon Rainforest, the Reserva Adolpho Ducke, in Manaus, and from protected areas of the municipality of Presidente Figueiredo, in Amazonas, Brazil. Previously, the species has been mistakenly assigned to the circumscription of the morphologically similar H. parvifolia, but differs in certain leaflet, inflorescence, and flower characteristics. The new species has a restricted distribution and is assessed as Endangered following IUCN Red List criteria. Based on herbarium collections and field studies, we present a full species description, an illustration, conservation status, and taxonomic comments. An identification key to the Hymenaea species of Brazil is also provided. There are six species of Hymenaea in the Amazon Basin, including the species described herein.

Cryptococcus gattii VGII isolated from native forest and river in Northern Brazil.

Cryptococcosis is a global invasive mycosis associated with significant morbidity and mortality. In the northern region of Brazil, this disease is caused by Cryptococcus neoformans genotype VNI and Cryptococcus gattii genotype VGII. However, few environmental studies have been conducted in this large tropical area. This study was performed to isolate, genotype, and determine the frequency of cryptococcal agents in environmental samples near Manaus, Amazonas, Brazil. A total of 970 environmental samples (290 from soil, 290 from decaying plants, 5 from insects, 280 from the Negro river, and 105 from small streams within the city of Manaus) were collected and plated on Niger seed agar. In addition, 20 sub-cultures obtained from each positive sample were analyzed by PCR-RFLP (URA5) and PCR for genotyping and determination of mating type. Six samples were positive for isolates from the C. gattii species complex. Of those, three samples were from Adolpho Ducke Forest Reserve and three were from the Negro river. All isolates were C. gattii genotype VGII (mating type MATα). Genotype VGII proved to be the most important genotype found in the environmental samples. The genotype VGII has been described as one of the most virulent and less susceptible to antifungals and responsible for important outbreaks. This is the first study to demonstrate isolation of C. gattii (VGII) from the Negro river.

Tiger talk

Tiger talk

Description of the pupa of Cnemida retusa (Fabricius, 1801) (Melolonthidae: Rutelinae)

Pupae of chafer beetle (Melolonthidae) Cnemida retusa (Fabricius, 1801) (Rutelinae, Rutelini) were collected in October and November of 2017 in a decaying log at Reserva Florestal Adolpho Ducke, Manaus, Amazonas, Brazil, and are described and illustrated. The pupa description is the first to the genus and a key to known pupae of Rutelini is added.

Comparative leaf anatomy of twenty species of Chrysobalanaceae R. Br

Anatomical characters are important for the identification of species, investigation of phylogenies and understanding autoecology. This study analyzed the leaf traits of twenty species of Chrysobalanaceae occurring in Adolpho Ducke Forest Reserve, Manaus, AM, Brazil. The species show scleromorphic features such as stomatal crypts, thick cuticle, and vascular bundles with extensions sheaths, indicating adaptations to the poor soil forest environment in which they occur, as well as to high light intensity and precipitation. Stomata above the epidermis line was a frequent character in Licania. Characteristics such as vascularization, midrib shape and presence of sclereids differed between species. None of the traits analyzed was exclusive to any of the genera studied. However, these traits can provide an important database for future phylogenetic studies within the family.

A new species of phlebotomine sandfly, Pintomyia (Pifanomyia) duckei (Diptera: Psychodidae) from Manaus, State of Amazonas, Brazil

ABSTRACT Pintomyia (Pifanomyia) duckei Oliveira, Alencar and Freitas sp. n. from Adolpho Ducke Reserve, Manaus, Amazonas state, Brazil, is described and illustrated based on three male specimens, the holotype and two paratypes. The paratypes have abnormalities in the external genitalia, one with asymmetric bilateral anomaly (different anomalies in each of certain paired structures) and the other with unilateral anomaly (anomaly in one of the paired structures). The new species probably belongs to the Serrana Series, integrating the list of the species whose males possess gonostylus with two stout spines (one apical and other subapical), as well as a small and very thin spine on the inner surface of the basal half.

Comparative Cytogenetics of Omophoita abbreviata and O. aequinoctialis (Coleoptera, Chrysomelidae, Alticini) from the Adolpho Ducke Forest Reserve in Brazilian Amazonia: Intrapopulation Variation in Karyotypes

The chromosomes of 2 flea beetle species from central Amazonia, Omophoita abbreviata and O. aequinoctialis (Alticini), were investigated through analysis of meiotic and mitotic cells. These species belong to the subtribe Oedionychina, a taxon that has unique cytogenetic features, such as giant sex chromosomes which are aligned at a distance during meiosis I (asynaptic). O. abbreviata and O. aequinoctialis have a meiotic formula of 10II + X + y, which is predominant in this subtribe. While the species of the genus Omophoita possess a relatively stable karyotype, a typical feature for Oedionychina, the present study identified inter- and intrapopulational variation in chromosome morphology, constitutive heterochromatin, and the presence and number of B chromosomes in O. aequinoctialis. In addition, FISH mapping of telomeric sequences revealed signals in the collochores, raising several questions on the chromosomal evolution in this group.

Differences in the decomposition of green and senescent leaves in streams of Reserva Florestal Adolpho Ducke (Amazonas, Brazil)

Leaves are considered the main energetic resource supply among all the allochthonous organic material available for the small shaded streams. However, their processing is limited by the physical and chemical characteristics of the leaves. Therefore, this research aimed to: i) evaluate the difference in decomposition coefficients between green and senescent leaves; ii) compare richness and density of aquatic invertebrates colonizing decomposing green and senescent leaves. Between November 2012 and January 2013, 12 leaf packages (6 senescent and 6 green) of 14 plant species were installed in 3 streams of the Reserva Florestal Adolpho Ducke (Manaus/AM - Brazil). After 15, 30 and 60 days the submerged packages were removed. The collected material was taken to the laboratory for analyzes of: aquatic invertebrates and leaves' mass remnants. Paired t-test was performed to verify if the decomposition coefficients (k) differed. ANCOVAs were performed to compare: the remaining mass (%), richness and density of aquatic invertebrates between leaf type over time. The green leaves presented higher leaf decomposition rates than in senescent ones. The leaf type influenced the average invertebrates densities. Therefore, green leaves were more susceptible to the colonization of aquatic invertebrates associated with the leaf decomposition process in small Amazonian streams.