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1.
Pol J Microbiol ; 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39074063

RESUMEN

The Victoria Falls rainforest is a protected site whose forest floors harbor a host of cellulolytic microorganisms involved in biomass degradation. This study collected decaying logs and soil from the rainforest for bioprospecting cellulases from their metagenomes. Metagenomic DNA was isolated from the compound sample. Degenerate cellulase primers were used to amplify cellulase genes in the metagenome. The resulting amplicons cloned into Z-competent Escherichia coli DH5α were analyzed by functional screening for the production of cellulase extracellularly. Functional screening of the clones resulted in one clone (Clone-i) testing positive for extracellular cellulase production. Submerged fermentation of Clone-i was carried out for cellulase production. The cellulases were characterized to determine their activity's optimum pH and temperature. The diversity of the cellulases produced by Clone-i was determined. Clone-i's optimum enzyme activity was observed after 72 hours of incubation at 50°C and pH 5. Clone-i produced 80% more exoglucanases as compared to endoglucanases. The cellulolytic Clone-i' isolate shows Victoria Falls rainforest's potential as an enzyme bioprospecting site, reflecting that metagenomics is a valuable tool in microbial ecology.

2.
Mol Ecol Resour ; 24(5): e13961, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38646932

RESUMEN

Over the past few years, insects have been used as samplers of vertebrate diversity by assessing the ingested-derived DNA (iDNA), and dung beetles have been shown to be a good mammal sampler given their broad feeding preference, wide distribution and easy sampling. Here, we tested and optimized the use of iDNA from dung beetles to assess the mammal community by evaluating if some biological and methodological aspects affect the use of dung beetles as mammal species samplers. We collected 403 dung beetles from 60 pitfall traps. iDNA from each dung beetle was sequenced by metabarcoding using two mini-barcodes (12SrRNA and 16SrRNA). We assessed whether dung beetles with different traits related to feeding, nesting and body size differed in the number of mammal species found in their iDNA. We also tested differences among four killing solutions in preserving the iDNA and compared the effectiveness of each mini barcode to recover mammals. We identified a total of 50 mammal OTUs (operational taxonomic unit), including terrestrial and arboreal species from 10 different orders. We found that at least one mammal-matching sequence was obtained from 70% of the dung beetle specimens. The number of mammal OTUs obtained did not vary with dung beetle traits as well as between the killing solutions. The 16SrRNA mini-barcode recovered a higher number of mammal OTUs than 12SrRNA, although both sets were partly non-overlapping. Thus, the complete mammal diversity may not be achieved by using only one of them. This study refines the methodology for routine assessment of tropical mammal communities via dung beetle 'samplers' and its universal applicability independently of the species traits of local beetle communities.


Asunto(s)
Escarabajos , Código de Barras del ADN Taxonómico , Mamíferos , Animales , Escarabajos/genética , Escarabajos/clasificación , Mamíferos/genética , Mamíferos/clasificación , Código de Barras del ADN Taxonómico/métodos , ARN Ribosómico 16S/genética , ARN Ribosómico/genética , Análisis de Secuencia de ADN/métodos , Biodiversidad , Metagenómica/métodos , ADN/genética , Heces/química
3.
Am J Bot ; 111(3): e16303, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38531667

RESUMEN

PREMISE: Vertical stratification is a key feature of tropical forests and plant-frugivore interactions. However, it is unclear whether equally strong patterns of vertical stratification exist for plant-nectarivore interactions and, if so, which factors drive these patterns. Further, nectar-inhabiting bacteria, acting as "hidden players" in plant-nectarivore interactions, might be vertically stratified, either in response to differences among strata in microenvironmental conditions or to the nectarivore community serving as vectors. METHODS: We observed visitations by a diverse nectarivore community to the liana Marcgravia longifolia in a Peruvian rainforest and characterized diversity and community composition of nectar-inhabiting bacteria. Unlike most other plants, M. longifolia produces inflorescences across forest strata, enabling us to study effects of vertical stratification on plant-nectarivore interactions without confounding effects of plant species and stratum. RESULTS: A significantly higher number of visits were by nectarivorous bats and hummingbirds in the midstory than in the understory and canopy, and the visits were strongly correlated to flower availability and nectar quantity and quality. Trochiline hummingbirds foraged across all strata, whereas hermits remained in the lower strata. The Shannon diversity index for nectar-inhabiting bacterial communities was highest in the midstory. CONCLUSIONS: Our findings suggest that vertical niche differentiation in plant-nectarivore interactions seems to be partly driven by resource abundance, but other factors such as species-specific preferences of hummingbirds, likely caused by competition, play an important role. We conclude that vertical stratification is an important driver of a species' interaction niche highlighting its role for promoting biodiversity and ecosystem functioning.


Asunto(s)
Ecosistema , Néctar de las Plantas , Animales , Bosques , Biodiversidad , Flores , Aves/fisiología
4.
Conserv Physiol ; 12(1): coad105, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38293637

RESUMEN

Fishing causes direct removal of individuals from wild populations but can also cause a physiological disturbance in fish that are released or discarded after capture. While sublethal physiological effects of fish capture have been well studied in commercial and recreational fisheries, this issue has been overlooked for the ornamental fish trade, where it is common to capture fish from the wild and discard non-target species. We examined metabolic responses to capture and discard procedures in the three-striped dwarf cichlid Apistogramma trifasciata, a popular Amazonian aquarium species that nonetheless may be discarded when not a target species. Individuals (n = 34) were tagged and exposed to each of four treatments designed to simulate procedures during the capture and discard process: 1) a non-handling control; 2) netting; 3) netting +30 seconds of air exposure; and 4) netting +60 seconds of air exposure. Metabolic rates were estimated using intermittent-flow respirometry, immediately following each treatment then throughout recovery overnight. Increasing amounts of netting and air exposure caused an acute increase in oxygen uptake and decrease in available aerobic scope. In general, recovery occurred quickly, with rapid decreases in oxygen uptake within the first 30 minutes post-handling. Notably, however, male fish exposed to netting +60 seconds of air exposure showed a delayed response whereby available aerobic scope was constrained <75% of maximum until ~4-6 hours post-stress. Larger fish showed a greater initial increase in oxygen uptake post-stress and slower rates of recovery. The results suggest that in the period following discard, this species may experience a reduced aerobic capacity for additional behavioural/physiological responses including feeding, territory defence and predator avoidance. These results are among the first to examine impacts of discard practises in the ornamental fishery and suggest ecophysiological research can provide valuable insight towards increasing sustainable practises in this global trade.

5.
Emerg Microbes Infect ; 13(1): 2307511, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38240324

RESUMEN

Dengue is often misclassified and underreported in Africa due to inaccurate differential diagnoses of nonspecific febrile illnesses such as malaria, sparsity of diagnostic testing and poor clinical and genomic surveillance. There are limited reports on the seroprevalence and genetic diversity of dengue virus (DENV) in humans and vectors in Nigeria. In this study, we investigated the epidemiology and genetic diversity of dengue in the rainforest region of Nigeria. We screened 515 febrile patients who tested negative for malaria and typhoid fever in three hospitals in Oyo and Ekiti States in southern Nigeria with a combination of anti-dengue IgG/IgM/NS1 rapid test kits and metagenomic sequencing. We found that approximately 28% of screened patients had previous DENV exposure, with the highest prevalence in persons over sixty. Approximately 8% of the patients showed evidence of recent or current infection, and 2.7% had acute infection. Following sequencing of sixty samples, we assembled twenty DENV-1 genomes (3 complete and 17 partial). We found that all assembled genomes belonged to DENV-1 genotype III. Our phylogenetic analyses showed evidence of prolonged cryptic circulation of divergent DENV lineages in Oyo state. We were unable to resolve the source of DENV in Nigeria owing to limited sequencing data from the region. However, our sequences clustered closely with sequences in Tanzania and sequences reported in Chinese with travel history to Tanzania in 2019. This may reflect the wider unsampled bidirectional transmission of DENV-1 in Africa, which strongly emphasizes the importance of genomic surveillance in monitoring ongoing DENV transmission in Africa.


Asunto(s)
Virus del Dengue , Dengue , Malaria , Humanos , Virus del Dengue/genética , Nigeria/epidemiología , Bosque Lluvioso , Estudios Seroepidemiológicos , Filogenia , Estudios Transversales , Malaria/epidemiología , Secuenciación Completa del Genoma
6.
PhytoKeys ; 227: 181-198, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37396012

RESUMEN

Flagelliflory refers to the production of inflorescences exclusively on long, whip-like branches which emerge from the main trunk and extend along the ground or below it. It is the rarest type of cauliflory and only a few cases have been reported in the world. Here, a new species of Annonaceae with flagelliflory is described and illustrated. The phylogenetic relationships of the new species were inferred using a hybrid-capture phylogenomic approach and we present some notes on its reproductive ecology and pollen characteristics. The new species, namely Desmopsisterriflorasp. nov., is part of a clade composed of Mexican species of Stenanona with long, awned petals. Desmopsisterriflora is distinguished by its flageliflorous inflorescences, basely fused sepals, thick red petals, reduced number of ovules per carpel, pollen grains with a weakly rugulate to fossulate exine ornamentation, and its globose, apiculate fruits with a woody testa. The morphological characteristics of the flagella suggest that these are specialized branches rather than inflorescences, and the absence of ramiflory implies an exclusively reproductive function. The flowers are infrequently visited by insects, their potential pollinators being flies and ants.

7.
Onderstepoort J Vet Res ; 90(1): e1-e13, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37265142

RESUMEN

Lymnaea natalensis is the only snail intermediate host of Fasciola gigantica, the causative agent of fascioliasis, in Nigeria. The species also serves as intermediate host for many other African trematode species of medical and veterinary importance, and it is found throughout the country. However, there is no detailed information on the factors that influence its distribution and seasonal abundance in the tropical aquatic habitats in Nigeria. This study used the geographic information system and remotely sensed data to develop models for predicting the distribution of L. natalensis in South-Western Nigeria. Both land surface temperature (LST) and normalised difference vegetation index (NDVI) were extracted from Landsat satellite imagery; other variables (slope and elevation) were extracted from a digital elevation model (DEM) while rainfall data were retrieved from the European Meteorology Research Programme (EMRP). These environmental variables were integrated into a geographic information system (GIS) to predict suitable habitats of L. natalensis using exploratory regression. A total of 1410 L. natalensis snails were collected vis-à-vis 22 sampling sites. Built-up areas recorded more L. natalensis compared with farmlands. There was no significant difference in the abundance of snails with season (p  0.05). The regression models showed that rainfall, NDVI, and slope were predictors of L. natalensis distribution. The habitats suitable for L. natalensis were central areas, while areas to the north and south were not suitable for L. natalensis.Contribution: The predictive risk models of L. natalensis in the study will be useful in mapping other areas where the snail sampling could not be conducted.


Asunto(s)
Fasciola , Fascioliasis , Animales , Lymnaea , Fascioliasis/veterinaria , Ecosistema , Estaciones del Año
8.
Neotrop Entomol ; 52(4): 584-595, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37310662

RESUMEN

Ants of the genus Solenopsis are globally distributed, presenting high diversity and many generalist species. In South America, the dominant species is Solenopsis saevissima (Smith, 1855), commonly found nesting in grassy fields surrounding humanized areas. In spite of being so common, there has been no research evaluating the effect of human disturbances on the mitochondrial DNA (mtDNA) haplotype diversity in this species. In this context, we here characterized the mtDNA haplotype diversity in S. saevissima nests by highway roadsides, dust roads, and forest borders of Atlantic Forest, based on partial sequences of cytochrome c oxidase subunit I (COI). Based on the facts that the species is a rapid colonizer of disturbed habitats, we specifically probed how the genetic diversity of native S. saevissima is impacted by highways and roads infrastructure expanding around the rainforest. Species diagnosis was established both by morphological characters and obtained mtDNA COI sequences. Overall, the species exhibited high haplotypes and nucleotide diversity, particularly around forest borders; though all haplotypes seemed closely related across the different habitats. We identified seven mitochondrial haplotypes (H1 to H7), where haplotype H1 was exclusively found in highway roadside nests, and H7 on dust roads; the remaining haplotypes were recorded from all habitats. Haplotype H1 was geographically isolated to the south of the Atlantic Forest, supporting previous suggestions that it acts as a biogeographical barrier. The pattern is suggestive of a recent species expansion, probably resulting from extensive habitat fragmentation. Taken together, our data demonstrates fire ant haplotypes prevailing in some anthropized habitats, characterizing how a native species lining the remnants of the Brazilian Atlantic Forest might be a concern for environmental conservation.


Asunto(s)
Hormigas , Humanos , Animales , Hormigas/genética , Haplotipos , Ecosistema , Bosques , ADN Mitocondrial/genética , Brasil
9.
PeerJ ; 11: e14975, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36935915

RESUMEN

Background: Efforts to alleviate the negative effects of oil spills in the Ecuadorian Amazon include remediation activities such as cleaning, reshaping, and revegetation of polluted areas. However, studies of the diversity of biological communities in these hydrocarbon-degraded ecosystems have never been carried out. Here, we evaluated the diversity of dung beetles on remediated soil ecosystems (Agricultural Soils and Sensitive Ecosystems) and on non-contaminated soils (Natural Forests and Palm Plantations). Methodology: The study was conducted in Sucumbíos and Orellana provinces, in the Ecuadorian Amazon at four sampling sites per ecosystem type (a total of 16 sites). At each sampling site, six pitfall traps remained active for 120 consecutive h per month for 1 year. Results: We collected 37 species and 7,506 individuals of dung beetles. We observed significant differences in mean species abundance, richness, and diversity between non-contaminated soil ecosystems and remediated soil ecosystems, with Natural Forests presenting the highest values, and Agricultural Soils the lowest values. Regarding sampling month, we also found significant differences among ecosystems, which were also higher in Natural Forests. Discussion: The results suggest that hydrocarbon-degraded ecosystems tend to conserve lower beetle diversity one year after remediation highlighting the importance of Natural Forests for the conservation of tropical biodiversity. Therefore, dung beetle diversity could be used for future landscape management of these hydrocarbon-degraded ecosystems.


Asunto(s)
Escarabajos , Ecosistema , Animales , Suelo , Escarabajos/fisiología , Ecuador , Bosques
10.
Biodivers Data J ; 11: e103667, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38327385

RESUMEN

Background: This revision is part of a continuing series of taxonomic work aimed at the description of new taxa and the redescription of known taxa of the Tachinidae of Area de Conservación Guanacaste in northwestern Costa Rica. Here we describe 33 new species in the genus Belvosia Robineau-Desvoidy, 1830 (Diptera: Tachinidae). All species described here were reared from this ongoing inventory of wild-caught caterpillars spanning a variety of families (Lepidoptera: Erebidae, Eupterotidae, Noctuidae, Notodontidae, Saturniidae, and Sphingidae). We provide a morphological description of each species with limited information on life history, molecular data, and photographic documentation. In addition to the new species, the authors provide a redescription of the genus Belvosia, as well as provide a key to the identification of the species present in the Meso- and North-American fauna. New information: The following 33 new species of Belvosia Robineau-Desvoidy, 1830, all authored by Fleming & Woodley, are described: Belvosiaadrianguadamuzi Fleming & Woodley sp. n., Belvosiaanacarballoae Fleming & Woodley sp. n., Belvosiaangelhernandezi Fleming & Woodley sp. n., Belvosiabrigittevilchezae Fleming & Woodley sp. n., Belvosiaalixtomoragai Fleming & Woodley sp. n., Belvosiacarolinacanoae Fleming & Woodley sp. n., Belvosiaciriloumanai Fleming & Woodley sp. n., Belvosiadiniamartinezae Fleming & Woodley sp. n., Belvosiaduniagarciae Fleming & Woodley sp. n., Belvosiaduvalierbricenoi Fleming & Woodley sp. n., Belvosiaeldaarayae Fleming & Woodley sp. n., Belvosiaeliethcantillanoae Fleming & Woodley sp. n., Belvosiafreddyquesadai Fleming & Woodley sp. n., Belvosiagloriasihezarae Fleming & Woodley sp. n., Belvosiaguillermopereirai Fleming & Woodley sp. n., Belvosiaharryramirezi Fleming & Woodley sp. n., Belvosiahazelcambroneroae Fleming & Woodley sp. n., Belvosiajorgehernandezi Fleming & Woodley sp. n., Belvosiajosecortezi Fleming & Woodley sp. n., Belvosiajoseperezi Fleming & Woodley sp. n., Belvosiakeinoraragoni Fleming & Woodley sp. n., Belvosialuciariosae Fleming & Woodley sp. n., Belvosiamanuelpereirai Fleming & Woodley sp. n., Belvosiamanuelriosi Fleming & Woodley sp. n., Belvosiaminorcarmonai Fleming & Woodley sp. n., Belvosiaosvaldoespinozai Fleming & Woodley sp. n., Belvosiapabloumanai Fleming & Woodley sp. n., Belvosiapetronariosae Fleming & Woodley sp. n., Belvosiaricardocaleroi Fleming & Woodley sp. n., Belvosiarobertoespinozai Fleming & Woodley sp. n., Belvosiarostermoragai Fleming & Woodley sp. n., Belvosiaruthfrancoae Fleming & Woodley sp. n., Belvosiasergioriosi Fleming & Woodley sp. n.Belvosiacanalis Aldrich, 1928 is reared and recorded from the inventory; new information relative to host is provided and the species is rediscribed.The following are proposed by Fleming & Woodley as new synonyms of Belvosia Robineau-Desvoidy, 1830: Brachybelvosia Townsend, 1927 syn. n., Belvosiomimops Townsend, 1935 syn. n.The following three new combinations are proposed as a result of the new synonymies: Belvosiabrasilensis (Townsend, 1927), comb. n.; and Belvosiabarbiellinii (Townsend, 1935), comb. n.The authors also propose the following new synonymies: Belvosiabrasilensis (Townsend, 1927) = Belvosiaaurulenta (Bigot, 1888), syn. n.; Belvosiapollinosa Rowe, 1933 = Belvosiaborealis Aldrich, 1928 syn. n.; Belvosiaweyenberghiana (Wulp, 1883) = Belvosiafuliginosa (Walker, 1853) syn. n.; Belvosiabrasiliensis Townsend, 1927 = Belvosiafuliginosa (Walker, 1853) syn. n.; Belvosialuteola Coquillett, 1900 = Belvosiaochriventris (Wulp, 1890) syn. n.; Belvosiasocia (Walker, 1853) = Belvosiaproxima (Walker, 1853) syn. n.; Belvosiachrysopyga (Bigot, 1887) = Belvosiaunifasciata (Robineau-Desvoidy, 1830) syn. n.; Belvosiachrysopygata (Bigot, 1888) = Belvosiaunifasciata (Robineau-Desvoidy, 1830) syn. n.

11.
Rev. biol. trop ; 70(1)dic. 2022.
Artículo en Español | LILACS, SaludCR | ID: biblio-1423030

RESUMEN

Introducción: La minería de oro a cielo abierto ocasiona impactos drásticos sobre los bosques naturales en regiones tropicales de alta biodiversidad, y la eficiencia de "revegetación", un proceso de resembrar y reconstruir el suelo, continúa siendo poco estudiado. Objetivo: Evaluar el efecto del tiempo sucesional y la distancia al bosque de referencia sobre la estructura biológica y composición de especies en minas de oro revegetadas. Métodos: Realizamos inventarios de vegetación en minas abandonadas en el bosque tropical lluvioso de Chocó, Colombia. Las minas contaban con 6, 10, 15, 19 y 24 años de sucesión natural. En cada escenario, establecimos cuatro parcelas de 2×50 m: a 50 m y 100 m de distancia desde el borde bosque-mina (ecotono). Resultados: Se identificaron 300 especies (193 géneros y 75 familias). La riqueza, diversidad y equitatividad cambian poco con el tiempo sucesional en las minas, pero alcanzan valores superiores en el bosque de referencia. La composición de especies es similar entre las minas con distinto tiempo sucesional, pero difiere ampliamente del bosque de referencia (solo 7 % de semejanza). La calidad del sustrato y las estrategias reproductivas de plantas herbáceas (principalmente Cyperaceae y Melastomataceae) y arbóreas (Cespedesia spathulata y Miconia reducens) que crecen espontáneamente en las minas, juegan un papel importante en la revegetación natural temprana. Conclusiones: 24 años de sucesión natural es poco tiempo para apreciar una recuperación sustancial de la vegetación en las minas si se compara con el bosque, y la distancia desde el ecotono parece no tener efecto significativo; sin embargo, la calidad de sustrato y estrategias reproductivas de plantas herbáceas son importantes en la etapa temprana de recuperación de las áreas impactadas por la minería de oro en Chocó.


Introduction: Open pit gold mining causes drastic impacts on natural forests in tropical regions of high biodiversity, and the efficacy of "revegetation", a process of replanting and rebuilding the soil, is still poorly studied. Objective: To evaluate the effect of successional time, and distance to the reference forest, on the biological structure and species composition of revegetated gold mines. Methods: We inventoried the adjacent forest and abandoned gold mines in the tropical rain forest of Chocó, Colombia. The mines had 6, 10, 15, 19 and 24 years of natural succession. In each scenario, we set four 2 × 50 m plots: two 50 m and two 100 m from the forest-mine edge (ecotone). Results: We identified 300 plant species (193 genera, 75 families). The richness, diversity and evenness changed little with successional time in the mines but reached higher values in the forest. The species composition was similar between the mines with different successional times but differed widely from the forest (only 7 % similarity). The substrate quality and reproductive strategies of herbaceous plants (mainly Cyperaceae and Melastomataceae) and trees (Cespedesia spathulata and Miconia reducens) that grow spontaneously in the mines, play an important role on the early natural revegetation. Conclusions: The 24 years of natural succession have been insufficient to reach a community of a complexity similar to that of the forest, and distance from the ecotone has no significant effect; however, the substrate quality and reproductive strategies of herbaceous plants are important in the early stages of mine recovery in the Chocó.


Asunto(s)
Restauración y Remediación Ambiental/estadística & datos numéricos , Minería , Colombia
12.
Front Plant Sci ; 13: 1004097, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36311137

RESUMEN

Transformation of tropical lowland rain forests into rubber tree and oil palm plantations is the cause of massive loss of vegetation diversity. The consequences for associated mycorrhizal fungi are not fully understood. We hypothesized that generalist arbuscular mycorrhizal fungi are resistant to removal of host species richness and that forest conversion to oil palm and rubber leads to loss of arbuscular mycorrhizal fungal (AMF) species with host preferences. Plant identities and AMF species were determined by molecular barcoding of 112 roots collected in three land-use systems (rain forest, rubber tree and oil palm plantation) in two landscapes on Sumatra (Indonesia), a world hotspot of forest transformation. The collected roots were from 43 forest plant species, in addition to rubber trees and oil palms. We detected 28 AMF species of which about 75% were present in forest trees and 25% shared among the land use systems. Only one AMF species present in plantation roots was not detected in the analyzed forest roots. Host specificity of arbuscular mycorrhizal fungi was not detected. Oil palm and rubber tree roots exhibited a strong reduction in AMF richness compared with roots from rainforests and were differentiated by soil resources. On basis of an individual root, oil palm had a lower AMF species richness than forest or rubber tree roots. Our results demonstrate that tropical AMF communities are shaped by two mechanisms: (i) root habitat diversity as the result of plant diversity and (ii) habitat properties as the result of plant traits or environmental conditions and management. Collectively, deterioration of habitat diversity and properties exacerbates impoverishment of AMF assemblages.

13.
Vet Sci ; 9(9)2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-36136685

RESUMEN

A 3- to 4-mo-old male ocelot (Leopardus pardalis) and a 6- to 8-mo-old female margay (Leopardus weidii) were brought in from the wild, held in captivity, and rehabilitated for 906 and 709 days, respectively, at the Rescate Wildlife Rescue Center in Costa Rica. During captivity, both cats were kept as isolated as possible from humans and fed appropriate live wild prey. After maturing and demonstrating the ability to capture and feed on live prey, the cats were radio-collared, released at a national wildlife refuge previously assessed for predator and prey occurrence, and monitored. After 54 days, the ocelot was trapped while preying on chickens in a nearby community, and after 20 days, the margay was found dead, likely due to ocelot predation. Avoiding habituation to humans, assuring hunting abilities, and assessing release sites likely is not sufficient to assure successful release of these species, and more experimental releases with innovative and detailed protocols and monitoring are needed.

14.
Primates ; 63(3): 195-215, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35441992

RESUMEN

This essay summarizes some of my findings while studying primates in the field from 1962 to 2018. Although I have studied primates throughout the tropics, I focused on Africa, primarily the Kibale Forest of Uganda. My research began in the early days of primate field studies when very little was known about the behavior and ecology of most species. Consequently, I was able to study nearly anything that could be observed under natural conditions. It was not necessary to specialize, and I opted to be a generalist. In much of my work I have attempted to understand the relationships between habitat quality, social organization, and population dynamics, emphasizing the great intraspecific variability that exists over time and between areas. Vocalizations have also long been of interest to me, starting with a description of predator-specific alarm calls and later showing how vocalizations among African monkeys appear to be evolutionarily stable. As my field experience progressed, I became increasingly involved with the conservation of tropical rain forests. In the last part of this essay I offer my thoughts on current trends in field primatology and some advice to the next generation of field biologists, stressing the importance of being a naturalist.


Asunto(s)
Ecología , Ecosistema , Animales , Bosques , Primates , Uganda
15.
Am Nat ; 199(4): 576-583, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35324380

RESUMEN

AbstractHummingbird flower mites are assumed to monopolize single host plant species owing to sexual selection for unique mating rendezvous sites. We tested the main assumption of the mating rendezvous hypothesis-extreme host specialization-by reconstructing interactions among tropical hummingbird flower mites and their host plants using DNA barcoding and taxonomic identifications. We collected 10,654 mites from 489 flowers. We extracted DNA from 1,928 mite specimens and amplified the cytochrome c oxidase I (CO1) DNA barcode. We analyzed the network structure to assess the degree of generalization or specialization of mites to their host plants. We recorded 18 species of hummingbird flower mites from three genera (Proctolaelaps, Rhinoseius, and Tropicoseius) interacting with 14 species of plants. We found that generalist mites are common, and congeneric mite species often share host plants. Our results challenge the assumption of strict specialization that supports this system as an example of mating rendezvous evolution.


Asunto(s)
Ácaros , Animales , Aves , ADN , Código de Barras del ADN Taxonómico , Flores , Ácaros/genética
16.
J Fish Biol ; 100(5): 1299-1310, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35302244

RESUMEN

The trichomycterid catfish Listrura menezesi, new species, is described from a flooded area adjacent to Rio das Panelas, Rio São João basin, Cachoeiras de Macacu municipality, Rio de Janeiro State, Brazil. It represents a most valuable remnant of Atlantic Forest biome that still resists the devastation of Brazilian coastlands. Listrura menezesi can be distinguished from its congeners, except L. boticario and L. depinnai, by the absence of a dorsal fin. It mainly differs from L. boticario and L. depinnai by a continuous midlateral dark stripe along the entire body (vs. discontinuous) and a longitudinal row of irregular dots along the dorsal limit of the abdomen extending for nearly the entire body (vs. only on the posterior half of the body in L. boticario and not forming a distinct row in L. depinnai). Although the new species shares with L. boticario and L. depinnai the absence of dorsal fin, recent phylogenetic analyses show a close relationship between L. menezesi and L. macaensis, the latter having a dorsal fin. A putative apomorphic condition for this clade is presented: the abrupt widening on the mesethmoid axis starting posteriorly on the horizontal through the middle region of the autopalatine (vs. anteriorly, on the horizontal through the anterior region of the autopalatine). Listrura menezesi comes as an addition to the ichthyofauna of the Rio São João drainage, a region extensively sampled for the past 20 years and supposedly well known. This paper also highlights the vulnerability of this species and the possibility of its disappearance in the near future.


Asunto(s)
Bagres , Animales , Brasil , Bagres/genética , Ecosistema , Filogenia , Ríos
17.
Photodiagnosis Photodyn Ther ; 38: 102788, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35235837

RESUMEN

BACKGROUND: A plant extract (EB) incorporated into glass ionomer cement (GIG) could be a potential photosensitizer for Antimicrobial PDT (aPDT) against caries-microorganisms, replacing methylene blue (MB), due to the presence of chlorophyll. GIC + EB + aPDT could be an therapeutic alternative to dentin decontamination and sealing, allowing reduction of operative time. OBJECTIVE: Evaluate Dioscorea altissima (EB) incorporated into GIC as a photosensitizer for aPDT against Streptococcus mutans. METHODS: Groups (n = 24; ntotal = 192): G1-GIC; G2-GIC + LASER; G3-GIC/EB; G4-GIC/EB + LASER; G5-GIC+MB; G6-GIC + aPDT; G7-GIC/EB + MB; and G8 - GIC/EB+aPDT. In aPDT groups, MB was the photosensitizer. In LASER groups, MB was not used. The irradiation protocol was 660 nm/100 mW/5 J/150 J/cm²/50 s, with a 5-min pre-irradiation time for the MB groups. Antibacterial assays were carried out in 24-well microplates. The wells were completed with one milliliter of a S. mutans in BHI at 1.3 × 108 CFU/mL suspension. After incubation, PDT or laser was performed. After MTT bacteria viability test, the data were submitted to the Kolgomorov-Smirnoff normality test, followed by one-way ANOVA and Tukey's posterior test, α < 0.05. RESULTS: Group G6 showed significant inhibition (p < 0.001), followed by groups G4, G5, G7, and G8, which did not show significant differences among them (p > 0.05). Groups G2 and G3 also showed similar results (p > 0.05) and were the least active compared to the others. CONCLUSIONS: EB potentiated the antimicrobial action of GIC against S. mutans and laser irradiation over GIC/EB presented better antimicrobials results. The results indicate that EB could be a potential photosensitizer for aPDT.


Asunto(s)
Antiinfecciosos , Fotoquimioterapia , Antibacterianos/farmacología , Antiinfecciosos/uso terapéutico , Biopelículas , Cementos de Ionómero Vítreo , Azul de Metileno/farmacología , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Extractos Vegetales/farmacología , Streptococcus mutans
18.
J Environ Manage ; 304: 114332, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34933270

RESUMEN

Understanding how functional traits and functional entities (FEs, i.e., unique combinations of functional traits) are distributed within plant communities can contribute to the understanding of vegetation properties and changes in species composition. We utilized investigation data on woody plants (including trees, shrubs and lianas) from 17 1-ha plots across six old-growth tropical forest types on Hainan island, China. Plant species were categorized as common (>1 individuals/ha) and rare species (≤1 individuals/ha) according to their abundance to determine how they contributed to different ecosystem functions. First, we assessed the differences in traits between common and rare species, and second, we examined functional redundancy, functional over-redundancy, and functional vulnerability for common and rare species of the forests. We found that both common species and rare species in each of the forest types were placed into just a few FEs, leading to functional over-redundancy and resulting in functional vulnerability. Rare species tended to have different trait values than those of common species, and were differently distributed among FEs, indicating different contributions to ecosystem functioning. Our results highlighted the disproportionate contribution of rare species in all of the studied forests. Rare species are more likely than common species to possess unique FEs, and thus, they have a disproportionately large contribution to community trait space. The loss of such species may impact the functioning, redundancy, and resilience of tropical forests.


Asunto(s)
Ecosistema , Clima Tropical , Bosques , Humanos , Plantas , Árboles
19.
Int J Syst Evol Microbiol ; 71(11)2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34726589

RESUMEN

During studies of yeasts associated with soil in a Cerrado-Atlantic Rain Forest ecotone site in Brazil, three orange-pigmented yeast strains were isolated from samples collected in Minas Gerais state, Brazil. Molecular analyses combining the 26S rRNA gene (D1/D2 domains) and the internal transcribed spacer (ITS) sequences as well as whole-genome sequence data showed that these strains could not be ascribed to any known species in the basidiomycetous genus Phaffia, and thus they are considered to represent a novel species for which the name Phaffia brasiliana sp. nov. is proposed. The holotype is CBS 16121T and the MycoBank number is MB 839315. The occurrence of P. brasiliana in a tropical region is unique for the genus, since all other species occur in temperate regions. Two factors appear to contribute to the distribution of the novel taxon: first, the region where it was found has relatively moderate temperature ranges and, second, an adaptation to grow or withstand temperatures higher than those of the other species in the genus seems to be in place.


Asunto(s)
Basidiomycota/clasificación , Filogenia , Bosque Lluvioso , Microbiología del Suelo , Basidiomycota/aislamiento & purificación , Brasil , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Técnicas de Tipificación Micológica , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
20.
PeerJ ; 9: e12244, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34820158

RESUMEN

Christiana mennegae is a phylogenetically enigmatic taxon and represents a case in point of a species whose presence escaped the radar of the Amazon lists and the Brazilian Flora project. Here we expand its distribution by adding new records from Peru and overlooked ones from Brazil. To investigate its phylogenetic placement in the Brownlowioideae, part of the rbcL gene of the plastid and the intergenic ITS2 region were sequenced. Macro- and micro-morphological investigation of features of C. mennegae using SEM of foliar, flower, fruit and seed structures are presented. A lectotype for the name is designated here. The morphology of trichomes revealed five types of trichomes ranging from glandular to branched and unbranched and we also report stomata on the seed surface for the first time in Brownlowioideae. Christiana mennegae and C. africana were recovered as sister species in the phylogenetic analysis, albeit with low to moderate support, and more species of this and closely related genera must be sampled and analyzed in order to obtain a clearer picture of the group's affinities and relationships. We provide an update of its conservation status from Vulnerable to Least Concern. We also highlight the need for investment in the digitization of biological collections, botanical capacity building at the local level and the importance of the availability of online literature to speed the study of Amazonian plant diversity.

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