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The genus Dyckia (Bromeliaceae) is endemic to South America, and its species show important ecological roles in xeric environments. The flowering phenology as well as floral and reproductive biology were monitored monthly in Dyckia dissitiflora at two sites (Bela Vista: 11°42′03.4″ S 39°05′21.7″ W and Barra do Vento: 11°37′58.1″ S 39°03′33.7″ W) in the municipality of Serrinha, Bahia, Brazil. Flowering occurs in the early austral summer with a peculiar time of beginning of anthesis (10:00–11:00), offering resources 18 h after the first petal movements. Pollen viability was 98%, with a high production of pollen grains. Stigma receptivity is continuous from flower opening to senescence, and nectar production initiates at 04:00 and extends until 18:00. The species is self‐compatible and autogamous, but not agamospermic. Pollen tubes developed and reached the micropyle within 24 h in all of the reproductive tests. The hummingbird Chlorostilbon lucidus was the only floral visitor and pollinator (frequency = 0.82 ± 0.02). Fruiting occurs 3 days after anthesis, and the seeds are wind‐dispersed. Self‐compatibility and autogamy are essential strategies for the reproductive success of D. dissitiflora in light of the low number and visit frequency of its pollinators, and it is favored by slow floral movements and the position of the stigmas in relation to stamens. [ABSTRACT FROM AUTHOR]

The species Sciopemyia sordellii (Diptera, Phlebotominae) is widely distributed throughout the American continent. This raises doubts about their identity as a single biological entity and points to the occurrence of species complex. Here, we review the geographic distribution of S. sordellii in the Neotropical region, as well as data on its biology and ecology. Records were obtained from literature and from specimens deposited in biological collections. In total, 149 records were analysed, from 12 countries in America. However, after taxonomic revision, some specimens were wrongly identified as S. sordellii, especially those from Peru, putting in doubt the occurrence of the species in that country. In Brazil, it has been recorded in all five geographic regions and collected in different biomes, besides to other ecotypes such as caves. Furthermore, its presence in an anthropized environment has also been reported. Some studies have also diagnosed Leishmania DNA in S. sordellii, indicating that parasite circulation is being maintained between the reservoir hosts. The data evaluated in our study allowed us to provide updated information on the distribution of S. sordellii in America, which may be useful in the taxonomy of this species. [ABSTRACT FROM AUTHOR]

We present information on the reproduction of Gymnodactylus darwinii based on macroscopic analysis of its gonads. We found no sexual dimorphism in body size (SVL) between adult males and females, but males had, on average, wider heads and longer forearms. Both sexes had very similar sizes at sexual maturity and maximum body sizes, suggesting male–male competition for resources does not occur, and/or there are no sexual differences in survival rates. The smallest specimen had 24 mm SVL, and juvenile/immature specimens of similar or slightly bigger sizes were collected throughout the year suggesting a continuous turnover of individuals in the population. Adult males showed a continuous reproductive cycle, contrasting with a seasonal cycle of females, where maximum gonadal volume was observed from September to December. This is not uncommon and may be related to differential response to local environmental conditions, or because distinct investment in reproduction. Females have a small and fixed clutch size (two eggs per clutch), a pattern also observed in its congener G. amarali and in many geckonids, which is likely due to phylogenetic inertia. To compensate for a fixed clutch size, females may be able to lay more than one clutch per reproductive season. [ABSTRACT FROM AUTHOR]

Four species of Gomesa (Gomesa flexuosa, Gomesa ranifera, Gomesa cornigera, and Gomesa riograndensis), a horticulturally important, albeit scarcely studied orchid genus, were investigated. Pollination biology was studied through fieldwork in Rio Grande do Sul in Southern Brazil during two flowering seasons. Breeding systems were studied through controlled pollinations in cultivated plants. All studied species secrete floral oils through elaiophores and are exclusively pollinated by native, oil‐collecting bees of the Centridini or Tapinotaspidini tribes. Pollinarium reconfiguration after withdrawal, a feature likely promoting cross‐pollination, was recorded in G. cornigera and G. riograndensis. All studied species are pollinator‐dependent and either predominantly or fully self‐incompatible, that is, unable to set fruit following self‐pollination. The used indexes of pollination efficiency consistently scored values below 1, indicating that in all studied species less than one flower is pollinated per pollinarium removed. Accordingly, pollen loss was high, ranging from 40% to 75%. Furthermore, inflorescences in natural populations displayed low fruit sets (below 13%). Gomesa flexuosa presented the highest values of pollinarium removal (36.24%) and deposition (15.34%). Significantly, this is the only studied species bearing a tabula infraestigmatica, a column swelling that bees hold to stabilize themselves while gathering the floral oils. Since pollinators were observed in all studied species spending considerable time (up to 3 min 46 s) and visiting several (up to 19) flowers, we propose that the observed low fruit set is the result of a combination of self‐incompatibility, pollinator‐mediated self‐pollination, and pollen loss. [ABSTRACT FROM AUTHOR]

The reproductive biology of Centropomus parallelus was described from 589 individuals captured in estuarine and coastal waters in Southern Brazil. Length‐frequency distribution showed the dominance of males in smaller length‐classes (132–290 mm LT), whereas females were dominant in larger length‐classes (>290 mm LT). Total length at maturity (L50) was 180 mm LT and corresponded to 29% of the maximum length recorded. Histological sections revealed one hermaphrodite (205 mm LT) and few immature females. Life history traits provided herein can contribute to sustainable fisheries management practices. [ABSTRACT FROM AUTHOR]

Since 2000, no reviews or analyses have been carried out on scientific studies regarding bat reproductive biology. Such reviews might contribute towards identifying information gaps and global research focus and trends.The objective of this work was to review and analyse scientific studies on different aspects of bat reproduction published in the last two decades (2000–2019), in order to provide perspective for future research.Using 19 key words, we searched for literature on the reproduction of bats published as book chapters and articles in scientific research journals globally. We analysed 36 chapters in 14 books and 276 scientific articles, from 41 countries, identifying publishing trends throughout the years, preferred journals, countries in which studies have been carried out, and most‐studied species and topics.The number of studies increased over the last decade, resulting from the consolidation of research lines in countries such as Brazil, India, Mexico, and USA. The studies covered 125 species, of which Scotophilus heathi and Cynopterus sphinx were the most recurrent, each appearing in 23 studies (7.4%, n = 312). The most common subject was anatomy (61 studies, 20%, n = 312), and the rarest was assisted reproduction techniques (11 studies, 3.5%, n = 312).In the last decade, there has been a trend to increase the study of male anatomy. The application of new techniques for the study of reproduction contributed to more complex studies that favour the understanding of the reproductive process. There is an evident lack of reproductive studies for most species, and there is an information gap regarding research in prenatal development and assisted reproduction techniques. These two topics are greatly significant for future research, because of their direct usefulness for species conservation. [ABSTRACT FROM AUTHOR]

The leaf‐cutting ant Atta bisphaerica Forel (Hymenoptera: Formicidae, Attini) forages leaves from monocotyledons in natural environments and is a serious pest of pastures and sugarcane plantations in Brazil. This study investigated aspects of the interactions between A. bisphaerica and dipteran Phoridae parasitoids. The seasonal and inter‐colonial variations in parasitism rates were also investigated. Ants from four A. bisphaerica colonies were sampled, with a total of 91 554 worker ants collected and evaluated. Of these ants, 4.4% were found to have been parasitized by three phorid species: Apocephalus attophilus Borgmeier (relative parasitism rate: 40%), Myrmosicarius grandicornis Borgmeier (31%), and Eibesfeldtphora bragancai (Brown) (28%). The months with the lowest average temperatures, lowest relative humidity, and lowest rainfall (characteristics of the dry season of the region under study) corresponded to the highest parasitism rates, especially by A. attophilus. Apocephalus attophilus and E. bragancai had the highest relative parasitism rates in two of the colonies, 45 and 41%, whereas M. grandicornis was the dominant species in each of the other two colonies, corresponding to approximately 40% of total parasitism. The variation in parasitism rates observed between colonies could be explained, at least in part, by the relationship between the size of the parasitoids and the size of the host ants. Concerning the biological characteristics, A. attophilus had the shortest life cycle, the highest successful emergence rate, and produced 2.5× more parasitoids per host. These characteristics, combined with the ability to cause higher levels of mortality of parasitized worker ants when compared to the two other phorid species, indicates that A. attophilus is an efficient natural enemy of A. bisphaerica and is therefore a candidate for a biocontrol program. [ABSTRACT FROM AUTHOR]

Brood‐site pollination mutualisms represent extreme levels of reciprocal specialization between plants and insects. Several studies have revealed intimate associations between cycads and their insect pollinators across different continents. However, the reproductive biology of South American cycads is still poorly understood, with limited empirical data available. Here, we investigated the plant–pollinator interactions of Zamia boliviana (Cycadales, Zamiaceae), which is distributed on savanna patches in Brazil and Bolivia. Our aim was to examine reproductive biology (strobili development and their visitors) to identify potential pollinators from the perspective of dioecy and expectations of obligatory mutualism. We monitored reproductive cohorts and registered the strobiliʼs visitors. We classified the visitorsʼ activities and described the behavior of the most active and recurring ones in both reproductive structures to ascertain the potential pollinators and their relationship with the Z. boliviana. In situ experiments were used to demonstrate efficacy in seed production. Although other insects visit the strobili, only one Coleoptera (Erotylidae: Pharaxonotha) was present seasonally. Pharaxonotha cerradensis was the single species capable of transporting pollen and developing a life cycle associated with polleniferous strobili, while concomitantly visiting ovuliferous strobili. Experimental tests associated with observational evidence in the cycad indicated brood‐site pollination mutualism with the Erotylidae beetle, a potential pollinator of Z. boliviana. Our investigation confirmed a new case of obligatory mutualism between cycads and P. cerradensis in the New World. Future research on Zamia from South America should address pollination systems of this genus to better understand the ecology and evolution of plant–pollinator interactions. [ABSTRACT FROM AUTHOR]

Uebelmannia pectinifera Buining subsp. pectinifera (Cactaceae) is an endangered species endemic to quartzitic rocks in campo rupestre vegetation of Minas Gerais state, Brazil. Understanding its reproductive biology and pollinators is needed for effective conservation planning for the species. The study took place in the Parque Nacional Sempre Vivas where 35 individuals were monitored. Analyses of floral morphology, pollen/ovule ratio, stigma receptivity and presence of osmophores were carried out, while observations of floral visitors were made and, according to their behavior, the potential pollinators were ascertained. The reproductive system of the plant was evaluated by means of manual self‐ and cross‐pollination and growth and morphology of pollen tubes were observed. The anthesis occurs by 06 a.m. and ends around 03 p.m., the flowers re‐opening for two days and finishing on the third day, being protandrous and melittophilous, offering pollen only. Two species of solitary bees (Ceratina sp. and Chilicola huberi) were observed pollinating the flowers, the female bees collecting pollen. The reproductive system is allogamic with endogamic self‐incompatibility and is served by specific pollinators. U. pectinifera subsp. pectinifera occurs in small populations, its reproduction relies on the presence of pollen‐gathering bees that also depend on the associated flora for nectar provision, highlighting the importance of maintaining its surrounding habitat in good condition. [ABSTRACT FROM AUTHOR]

Dyckia is the third most diverse genus from Pitcairnoideae, pollinated mainly by insects and hummingbirds. In this study, we evaluated demography, reproductive biology and pollination of Dyckia excelsa, a saxicolous species typical of ironstone outcrops. It occurs in groupings composed of genets, ramets and seedlings and bloomed several times, principally in September, with fruiting and dispersing of seeds in November. The anthesis is diurnal and flowers remain open for 2 days. Nectar volume decreased during the anthesis, whereas nectar sugar concentration remained constant. Dyckia excelsa is partially self‐compatible and xenogamic; the highest fruit set was observed in the control and cross‐pollination treatments; high seed germination rates were observed in all treatments. Flowers have the ornithophilous syndrome, but hummingbirds, bees and butterflies visited them. The occurrence of groupings with multiple inflorescences could contribute to geitonogamy. The high number of flowers during a year supplies food resources and ensures the fidelity of pollinators. [ABSTRACT FROM AUTHOR]

Phyllophaga capillata (Blanchard) is the most important soil pest in soybean crops in Central Brazil (Federal District and Goiás state). The objective of this work was to study the bio‐ecology of P. capillata in the field in the Cerrado of Central Brazil, relating its biology and behaviour to the climatic characteristics of this biome. The study was conducted over three years in a soybean [Glycine max (L.) Merr.] production area (≈6000 ha) in the Federal District. Field samplings were taken to observe the biological stages of P. capillata, preferred oviposition sites and the adult swarming period. Phyllophaga capillata presented an univoltine cycle that lasted about 10 months of egg to inactive adults, and 12 months until the appearance of active adults. Eggs were found in the field in October and November. The larval stage occurred between November and June. Pre‐pupae were observed in June and the pupae between July and August. Inactive adults were observed in August and September, and the swarming period was between September and December. Females preferred to oviposit in sites with taller plants. This species synchronises its active phases (larvae and active adults) with soybean cultivation and the rainy season (October/March) in the Brazilian Cerrado. Alternatives for pest management based on their bio‐ecological characteristics are presented. [ABSTRACT FROM AUTHOR]

Five color morphs of Paracentrotus gaimardi can be distinguished along the coast of Rio de Janeiro, Brazil: black, brown, gray, green, and pink. All co-occur and are apparently exposed to similar environmental conditions. This study compares the morphology of these color morphs and investigates their gametic compatibility. All specimens of the five color morphs matched earlier descriptions of the species. The number of lateral spines on globiferous pedicellariae, the presence of small ophicephalous pedicellaria, and the pattern of distribution of pedicellaria on the test were reliable morphological characters for taxonomic purposes. The five color morphs were not clearly differentiable in terms of morphology. Fertilization success in crosses within color morphs was greater than in the majority of heteromorphic crosses. Only three heteromorphic crosses - ♀gray and ♂brown, ♀black and ♂gray, and ♀brown and ♂black - were as successful as control, within-color morph crosses. Therefore, some color morphs seem to be partially isolated by an incipient barrier to fertilization. Low fertilization rates among color morphs should result in genetic divergence among them. In fact, genetic divergence at bindin and ATPase genes has been reported among color morphs of P. gaimardi. Natural selection seems to favor fertilization within color morphs, but the mechanism for this differentiation in gametic compatibility is not known. [ABSTRACT FROM AUTHOR]

In the Juramento Reservoir, south-eastern Brazil, the white piranha Serrasalmus brandtii showed a prolonged reproductive season, with evidence for multiple spawning and a reproductive peak associated with seasonal rains. The egg surface exhibited a honeycomb-like pore canal arrangement and an adhesive apparatus surrounding the micropyle. Electron microscopic analysis suggests a role for the micropylar cell and neighbouring follicular cells in secretion of substances for egg attachment. [ABSTRACT FROM AUTHOR]

Tropical savanna and forest are recognized to represent alternate stable states, primarily determined by feedbacks with fire. Vegetation-fire dynamics in each of these vegetation types are largely determined by the influence of the vegetation on fire behavior, as well as the effects of fire behavior on tree mortality, topkill (defined here as complete death of the aerial biomass, regardless of whether the plant recovers by resprouting), and rate of growth of resprouts. We studied the effect of fire on three savanna-forest boundaries in central Brazil. Fire intensity was greater in savanna than forest, as inferred by a twofold greater height of stem charring. Despite lower fire intensity, forest tree species exhibited higher rates of topkill, which was best explained by their thinner bark, relative to savanna species. Following topkill, there was no tendency for sprouts of savanna trees to grow faster than those of forest species, contrary to expectations, nor was whole-plant mortality higher in forest than in savanna. This contrasts with observations of high rates of postburn mortality in many other tropical forests. The low tree mortality in these transitional forests suggests that the dynamic of these natural savanna-forest boundaries is fundamentally different from that of forest boundaries originating from deforestation in the humid tropics. The forests studied here appear to be much more resilient to occasional incursion of fire from the savanna, despite being unable to invade frequently burned savanna. The thin bark of forest species makes them particularly susceptible to the "fire trap," whereby repeated topkill of small trees prevents recruitment into adult size classes. Rapid growth will be particularly important for forest species to escape the fire trap, so we predict that, where fire is frequent, forests should be restricted to high-resource sites. Here, Mg2+ and Ca2+ concentrations had particularly strong effects on postburn growth rates, suggesting that these elements may most strongly limit the distribution of forest in these fire-prone savannas. [ABSTRACT FROM AUTHOR]

Rineloricaria isaaci is described from tributaries of the Uruguay River basin in Argentina, Brazil and Uruguay. The new species is distinguished by having a long and wide area of naked skin at the snout tip, surpassing the anteriormost pore of the infraorbital ramus of the sensory canal, approximately in the middle of the third postrostral plate, and by its particular sexual dimorphism characterized by the long pectoral and pelvic fins of mature males. [ABSTRACT FROM AUTHOR]

Previous studies have shown that macroecological variables such as body size and geographical range size may influence the probability of a species being described. We evaluated the description pattern of tiger moth species from the Brazilian Cerrado, and tested whether the date of description was influenced by the species biological attributes (body size, colour pattern, geographical range size, altitudinal range, latitudinal range, longitudinal range, degree of specificity to the Cerrado, and number of species of the same genus). The relationship between date of description for several arctiid taxa and predictor variables was investigated using simple and multiple regressions. All predictor variables explained significant variance in the year of description in some arctiid taxonomic groups. However, the relative importance of each predictor varied among taxa. Our analyses suggested that the tiger moths yet to be discovered in the Cerrado region will probably be small, with a restricted distribution, and endemic to the biome. We also showed, for the first time, that colour pattern is a significant variable in determining the description date of an animal group, with aposematic species being described first. We noted a significant decrease in numbers of tiger moth taxonomists in recent decades. The training of new tiger moth taxonomists is urgent because there is a significant relationship between the number of taxonomists and the number of described species. [ABSTRACT FROM AUTHOR]

Many studies have tested the performance of terrestrial vertebrates as surrogates for overall species diversity, because these are commonly used in priority-setting conservation appraisals. Using a database of 3663 vertebrate species in 38 Brazilian ecoregions, we evaluated the effectiveness of various subsets for representing diversity of the entire vertebrate assemblage. Because ecoregions are established incorporating information on biotic assemblages, they are potentially more amenable to regional comparison than are national or state lists. We used 10 potential indicator groups (all species; all mammals, birds, reptiles, or amphibians; all endemic species; and endemic species within each class) to find priority sets of ecoregions that best represent the entire terrestrial vertebrate fauna. This is the first time such tests are employed to assess the effectiveness of indicator groups at the ecoregion level in Brazil. We show that patterns of species richness are highly correlated among mammals, birds, amphibians, and reptiles. Furthermore, we demonstrate that ecoregion sets selected according to endemic species richness captured more vertebrate species per unit area than sets based on overall vertebrate richness itself, or than those selected at random. Ecoregion sets based on endemic bird, endemic reptile, or endemic amphibian richness also performed well, capturing more species overall than random sets, or than those selected based on species richness of one or all vertebrate classes within ecoregions. Our results highlight the importance of evaluating biodiversity concordance and the use of indicator groups as well as aggregate species richness. We conclude that priority sets based on indicator groups provide a basis for a first assessment of priorities for conservation at an infracontinental scale. Areas with high endemism have long been highlighted for conservation of species. Our findings provide evidence that endemism is not only a worthwhile conservation goal, but also an effective surrogate for the conservation of all terrestrial vertebrates in Brazil. [ABSTRACT FROM AUTHOR]

The side-effects of six pesticides used on peaches in Brazil were tested on the hymenopteran egg parasitoid Trichogramma cacoeciae using four laboratory tests: (a) adult parasitoid exposure to fresh pesticide residue on glass plates (worse case); (b) direct spray of host eggs enclosing the parasitoid egg, larvae or pupae (less-exposed life stages); (c) exposure of adults to pesticide residues on plant leaves at different intervals after application (persistence); (d) Dose–response pesticide exposures of adults on glass plates. Two dose rates were used: (1) The highest recommended field dosage (FD) and (2) the predicted initial environmental concentrations (PIEC). The results showed that the preparations greatly differed in their initial toxicity and persistence. The insecticide Valient® (methoxyphenozide) and the fungicide Venturol® (dodine) were considered harmless to T. cacoeciae adults as they fell into the class 1 category according to the guidelines of the International Organization for Biological Control (IOBC) when parasitoids were directly exposed to chemical residues. The insecticide/acaricide Assist® (mineral oil) was slightly harmful at the rate of PIEC 0.4 (40% of FD) and moderately harmful at FD. Pesticides in the categories harmless and moderately harmful can be considered for use in integrated pest management (IPM). The fungicide/acaricide Kumulus DF® (sulphur) and the insecticides Dipterex® 500 (triclorfon ) and Lebaycid® 500 (fenthion) were harmful at both concentrations. In the persistence test, Assist® was short lived and therefore may in special cases (i.e. reduced direct contact) be considered for use in IPM, but Kumulus® DF, Dipterex® 500 and Lebaycid® 500 constantly reduced parasitism between 77 and 100% and were rated as persistent (more than 30 days). The direct spray of parasitized host eggs at intervals after parasitism showed that Assist® and Kumulus® DF were harmless to the parasitoid egg, larvae and pupae within the host eggs. Dipterex® 500 was slightly harmful when sprayed one day after parasitism (parasitoid egg) and moderately harmful to the other two stages (larvae and pupae). Lebaycid® 500 was harmful to the parasitoid egg and larvae and moderately harmful to the pupae. The dose–response test showed that Kumulus® DF and Dipterex® 500 were toxic to T. cacoeciae. Kumulus® DF was harmful from 1 PIEC 0.4 to 0.125 PIEC 0.4 dosages and was slightly harmful with 0.0625 PIEC 0.4 dosage. Dipterex® 500 was harmful to T. cacoeciae in all the dosages tested. [ABSTRACT FROM AUTHOR]

Reports results of interviews and tests carried out with students after they have been taught the topic of evolution in Brazilian schools. Key concepts of evolution; Assessment of the Biology textbook; Social reconceptualizations.

Ferraz et al. (2008) indicated the need for planning in biological monitoring in the Amazon, and reviewed what they considered recent progress. The problems and solutions they discuss are well known, and it is unlikely that many biologists would disagree with most of them. However, the authors do not indicate that most of these issues are already being addressed in practice in the Amazon, especially by the Programa de Pesquisas em Biodiversidade (PPBio) of the Brazilian Ministry of Science and Technology. The only major issue about which we do not agree with Ferraz et al. (2008) relates to the design of monitoring programs. The authors recommended tailoring experimental designs to specific threats, which will result in a multitude of idiosyncratic designs and incompatible data sets. We suggest that generic broad-scale designs will allow us to answer more questions with greater confidence, because the investment in each location provides information about regional and global questions. Although specific designs may be more effective in some cases, there are insufficient resources available to install different research infrastructure for every possible threat. [ABSTRACT FROM AUTHOR]

To determine risk factors for HIV-1 among drug injectors in Rio de Janeiro, where cocaine is the dominant drug of injection, subjects were recruited using the criteria and interview instrument of the World Health Organization's Cross-National Study of HIV infection and risk behaviour in injecting drug users. HIV antibody test results were derived both from serum tests and from self-reports of previous tests (documented evidence of self-reported seropositivity was required). The analytical sample consists of 123 subjects, recruited both at drug abuse treatment sites and at street locations. Of 27 subjects with both serological and self-reported antibody status data, 20 reported previous negative tests; of these three had positive sera and may have seroconverted. Seven subjects reporting prior positive serostatus all tested positive. For the 123 subjects, seroprevalence was 34%. Independent significant risk factors in multivariate logistic regression with backwards elimination are: years of injection greater than 5; being a male who has had sex with men in the previous 5 years; and not having taken deliberate steps to protect oneself against AIDS. These findings indicate that homosexual/bisexual male drug injectors may be a bridge group through which HIV is entering drug-injecting networks in Rio de Janeiro. Efforts by drug injectors to reduce their risk of infection seem to have protective effects. This underscores the importance of HIV prevention efforts aimed at drug injectors.