Chlorostilbon Aureoventris Research Articles

Predation of Chlorostilbon lucidus (Shaw, 1812) (Apodiformes: Trochilidae) hummingbird chicks by Polistes canadensis (Linnaeus, 1758) (Polistinae: Polistini): A new predatory interaction documented in the Brazilian Caatinga

Non-aggressive interactions between Neotropical social wasps (Vespidae) and birds frequently occur but remain poorly understood. Typically categorized as commensalism, where birds benefit while no advantages for the wasps have been documented, the intricate dynamics of these associations have gone unexplored. These wasps, which are generalist feeders primarily relying on nectar, fruits, arthropods, and carrion, are seldom reported as vertebrate predators. In this study, we present a novel observation of the red social paper wasp, Polistes canadensis (Linnaeus, 1758) (Polistinae: Polistini), preying on young glittering-bellied emerald hummingbirds - Chlorostilbon lucidus (Shaw, 1812) (Apodiformes: Trochilidae), opportunistically recorded in the urban area of Brazilian Caatinga biome. Predation occurred when a Polistes canadensis individual targeted a hummingbird's nest. This occurrence challenges the prevailing view of these associations and suggests that social wasps may play a more significant role as nestling predators than previously acknowledged, highlighting the need for further research.

Autogamy ensures reproductive success in the bromeliad Dyckia dissitiflora Schult.f., endemic to the Brazilian caatinga domain

AbstractThe 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.

Bird migrant assemblages in urban and rural areas of central Argentina: a regional-scale comparison


 
 
 Migrant birds are negatively impacted by urbanization. However, most of the studies about urbanization effects on migrant birds were conducted in the Northern Hemisphere, and studies performed in South America are scarce. This study compares the migrant bird assemblages of urban parks and rural areas of cen- tral Argentina. Summer migrant birds were surveyed by standardized point counts in urban parks of six cities. In contrast, rural migrant assemblages were assessed through species lists of the citizen science project eBird in six paired sites. Sample coverage was similar between urban parks and rural areas (0.89 and 0.92, respectively). Migrant species richness was higher in rural than in urban parks. Migrant species composition changed between habitats, and species turnover was the dominant aspect of species dissimilarity. Urban parks had more occurrences of the Glittering-bellied Emerald (Chlorostilbon lucidus) and the Tropical Kingbird (Tyrannus melancholicus), whereas rural sites had more occurrences of the Vermillion Flycatcher (Pyrocephalus rubinus) and the Double-collared Seedeater (Sporophila caerulescens). Grasslands present in rural areas may favor the presence of the Vermillion Flycatcher and the Double-collared Seedeater. Therefore, cities are related to significant changes in the migrant bird communities.
 
 

Handroanthus impetiginosus (BIGNONIACEAE) AS AN IMPORTANT FLORAL RESOURCE FOR SYNANTHROPIC BIRDS IN THE BRAZILIAN SEMIARID

Handroanthus impetiginosus (Bignoniaceae) is commonly used in urban afforestation in the Brazilian semiarid, and it attracts native urban fauna during the dry season, when the plants are flowering. We conducted focal observations on nine flowering H. impetiginosus in an urban area at Brazilian semiarid to record the bird species that used flowers as a food resource and their behavior. We recorded four species of visiting birds at the H. impetiginosus flowers: Eupetomena macroura , Chlorostilbon lucidus , Icterus pyrrhopterus and Tangara sayaca . Of these, E. macroura and C. lucidus were observed on illegitimate visits, not contributing to the pollination, and E. macroura was the most aggressive species. Icterus pyrrhopterus and T. sayaca feeding on parts of the flowers or flower buds, generally promoting the flower abscission to access the nectar. The presence of H. impetiginosus can support generalist nectarivorous bird species, as E. macroura , C. lucidus and I. pyrrhopterus , and bees, as Xylocopa spp. in urban areas, which may contribute to the pollination of other native plant species in reforestation projects in this semiarid region.

Forest fragmentation negatively affects common bird species in subtropical fragmented forests

ABSTRACTForest fragmentation threatens bird species throughout the world. Previous studies suggest that the sensitivity of bird species to forest fragmentation is related to food abundance, and that this could be a key factor in understanding demographic changes. We assessed the relationship between forest fragment size, isolation and food abundance and the abundance of seven common species of birds in southern Chaco forests of Argentina, which use different food items, and are involved in different ecosystem processes. The relative abundance of Turdus amaurochalinus (Creamy-bellied Thrush) and Saltator aurantiirostris (Golden-billed Saltator) significantly decreased with patch size reduction, whereas the relative abundance of Taraba major (Great Antshrike) decreased with patch isolation and increased with arthropod abundance. Chlorostilbon lucidus (Glittering-bellied Emerald), Elaenia parvirostris (Small-billed Elaenia), Polioptila dumicola (Masked Gnatcatcher) and Zonotrichia capensis (Rufous-collared Sparrow) appeared to be resilient to forest fragmentation. Body size was a good predictor of bird sensitivity, as only the largest species were negatively correlated with forest fragmentation. Previous work suggests that birds inhabiting Chaco forests may be resilient to forest fragmentation. This needs to be reconsidered in the light of our results since the abundance of three out of seven common bird species was negatively related to forest fragmentation.

Generalized food-deceptive pollination in four Cattleya (Orchidaceae: Laeliinae) species from Southern Brazil

We studied the breeding system and pollination biology of Cattleya coccinea, C. intermedia, C. purpurata and C. tigrina in native populations from Rio Grande do Sul, Southern Brazil. At the State level, the three latter species are considered under risk of extinction and this work is intended to be a contribution towards their conservation and management. To date, their pollination needs and breeding system remain unknown.Breeding system was elucidated through controlled pollinations applied to isolated plants. Pollination was studied in the field, by means of photographic and filmic records. Cattleya purpurata, C. intermedia and C. tigrina are pollinated by large native Apidae bees of the genera Bombus, Xylocopa and Epicharis that bear the pollinaria on the scutellum and mesonotum. In spite of their differences in colour and perianth size, bee-pollinated species share a number of flower features which are absent in C. coccinea. The latter species is pollinated by the hummingbird Chlorostilbon lucidus (Trochilidae). In agreement, flowers of C. coccinea present a set of flower features normally associated to ornithophily. All studied species lack rewards and deceive their food-seeking pollinators. All species are self-compatible but pollinator-dependent. Fruiting success following manual self-pollination and cross-pollination did not differ, except in C. coccinea. However, in all species fruit from cross-pollinations yielded significantly higher numbers of viable seed. All studied species displayed low visitation rates, low natural fruit set (ranging from 0.5 to 14%) and Nilsson’s male efficiency factor of less than one, indicating that less than one flower was pollinated per pollinarium removed.All these features are consistent with those of other orchid groups pollinated through generalized food-deception.

Feeding behavior by hummingbirds (Aves: Trochilidae) in artificial food patches in an Atlantic Forest remnant in southeastern Brazil

ABSTRACT During flight, hummingbirds achieve the maximum aerobic metabolism rates within vertebrates. To meet such demands, these birds have to take in as much energy as possible, using strategies such as selecting the best food resources and adopting behaviors that allow the greatest energy gains. We tested whether hummingbirds choose sources that have higher sugar concentrations, and investigated their behaviors near and at food resources. The study was conducted at Atlantic forest remnant in Brazil, between June and December 2012. Four patches were provided with artificial feeders, containing sucrose solutions at concentrations of 5%, 15%, 25% and 35% weight/volume. Hummingbird behaviors were recorded using the ad libitum method with continuous recording of behaviors. The following species were observed: the Brazilian ruby Clytolaema rubricauda (Boddaert, 1783), Violet-capped woodnymph Thalurania glaucopis (Gmelin, 1788), Scale-throated hermit Phaethornis eurynome (Lesson, 1832), White-throated hummingbird Leucochloris albicollis (Vieillot, 1818), Versicoloured emerald Amazilia versicolor (Vieillot, 1818), Glittering-bellied emerald Chlorostilbon lucidus (Shaw, 1812) and other Phaethornis spp. C. rubricauda, P. eurynome and Phaethornis spp. visited the 35%-sucrose feeders more often, while the T. glaucopis visited the 25%-sucrose feeders more often. L. albicollis and A. versicolor visited more often solutions with sugar concentration of 15%. C. lucidus visited all patches equally. Three behavioral strategies were observed: 1) C. rubricauda and T. glaucopis exhibited interspecific and intraspecific dominance; 2) the remaining species exhibited subordinance to the dominant hummingbirds, and 3) P. eurynome and Phaethornis spp. adopted a hide-and-wait strategy to the dominant hummingbird species. The frequency of aggressive behaviors was correlated with the time the hummingbird spent feeding, and bird size. Our results showed that hummingbirds can adopt different strategies to enhance food acquisition; that more aggressive species feeding more than less aggressive species; and that the birds, especially if they were dominant species, visited high quality food resources more often.

Flowers visited by hummingbirds in the open habitats of the southeastern Brazilian mountaintops: species composition and seasonality.

The hummingbird-visited plant community located on the open-habitat mountaintop of the Espinhaço Range was studied for two years (from August 2007 to July 2009) in Serra do Cipó National Park, Southeastern Brazil (19° 15' S and 43° 31' W). The floral characteristics and flowering period of the hummingbird-visited plants was monthly recorded along trails located in three vegetation types: (1) typical campos rupestres (TCR), (2) open fields (OPF), and (3) capões de mata (CAM). Hummingbird visitation was observed in 51 plant species, 22 ornithophilous and 29 non-ornithophilous species. The TCR showed the greatest number of species visited (N = 38), followed by the OPF (N = 18) and CAM (N = 17). Six species of hummingbirds were recorded visiting flowers: Augastes scutatus, Campylopterus largipennis, Colibri serrirostris, Chlorostilbon lucidus, Eupetomena macroura and Phaethornis pretrei. This study demonstrates that the species richness and the number of ornithophilous species visited by the hummingbirds at the study site are more similar to hummingbird-plant communities of the Atlantic Forest than to those of the Cerrado communities and other Brazilian highland open-habitat communities. The plant families most visited by hummingbirds were Bromeliaceae and Asteraceae. Although the Asteraceae family is rarely used as a food resource for hummingbirds in other high and lowland communities, in the study site this family is used mainly by the endemic hummingbird Augastes scutatus. We found a large overlap of flowering throughout the year among the species visited by the hummingbirds. Thus, the nectar availability supports these resident hummingbirds. The present study also showed that the studied hummingbird-plant community is composed of many species endemic to the campos rupestres of the Espinhaço Range, some of which are considered to be in danger of extinction, thus constituting a unique and threatened community. Thus, understanding hummingbird-plant pollination dynamics becomes fundamental to the conservation of the campos rupestres.

Further comments on the application of the name Trochilus lucidus Shaw, 1812

A recent paper discussed the priority of the name Trochilus lucidus Shaw, 1812 over Ornismya aureoventris d’Orbigny & Lafresnaye, 1838, for the Glittering-bellied Emerald and the reasons why the senior name cannot be considered a nomen oblitum according to the rules of zoological nomenclature. However, all details concerning the application of the name have not been fully addressed, raising concerns among several ornithologists on the application of Shaw’s name. Here we discuss in detail why the name Trochilus lucidus must be applied to the Glittering-bellied Emerald. All morphological characters of Azara’s “El Mas Bello” hummingbird (upon which the name lucidus was based) agree perfectly with the Glittering-bellied Emerald, reinforcing its status as the valid, senior available name to that species. This conclusion has been historically accepted by almost all ornithologists who have studied the case.

Use of feces to attract insects by a Glittering-bellied Emerald, Chlorostilbon lucidus (Shaw, 1812) (Apodiformes: Trochilidae)

This study describes the occurrence of a female Glittering-bellied Emerald, Chlorostilbon lucidus , using feces to attract insects to the nesting site for predation. This is the first report of a hummingbird using feces to attract insects.

Birds as potential pollinators of the Spathodea nilotica (Bignoniaceae) in the urban environment.

Birds play crucial role on the pollination of many plants. However, little is known about the interactions between nectarivorous neotropical birds and exotic Angiosperms. S. nilotica is an exotic African plant widely used in Brazilian urban landscaping. However, it has been poorly studied in relation to its interactions with Neotropical birds. In this way, we studied the feeding nectar strategies and the interspecific antagonistic behaviours among nectarivorous Neotropical birds to verify the bird contributions to the S. nilotica pollination. The study was conducted from May 2008 to April 2011, but only in months of S. nilotica flowering (April to May). From 148 hours of sampling we identified 16 species feeding nectar on S. nilotica: 13 hummingbirds (Trochilidae), Aratinga aurea (Psittacidae), Tangara palmarum (Thraupidae) and Coereba flaveola (Coerebidae). Eupetomena macroura was the most frequent (96.88%), followed by Chlorostilbon lucidus (78.13%) and Coereba flaveola (59.38%). Most birds obtained nectar by punching at the base of the corolla, except for A. aurea that obtained the nectar by the upper opening of the petals in 100% of its visits, Heliomaster furcifer (95.65%), F. fusca (95%) and A. nigricollis (70.27%). Despite E. macroura also obtains nectar only by punching at the base of the corolla, it showed the highest level of legitimate visits. Antagonistic events were more frequent in E. macroura (58.65%), Florisuga fusca (11.04%) and Amazilia fimbriata (10.87%), being E. macroura dominant in all events. These results showed E. macroura plays an important role on this plant being the most important bird as a potential pollinator. Moreover, other birds contribute partially to the S. nilotica pollination. Most probably it is a result of recent Neotropical bird interactions with this African plant.

Cuphea melvilla Lindlay (Lythraceae): uma espécie do Cerrado polinizada por beija-flores

Cuphea melvilla é uma espécie peculiar dentro de um gênero majoritariamente melitófilo. Dois agrupamentos de indivíduos, em bordas das matas de galeria do Córrego do Panga, Uberlândia, MG, foram estudados com o objetivo de investigar o sistema de polinização e sistema de reprodução da espécie na região. O estudo foi realizado de janeiro a junho de 1999. Cuphea melvilla é uma espécie arbustiva com características morfológicas e eventos florais que confirmam sua adaptação à polinização por beija-flores. A floração foi longa, com início em Janeiro, em plena estação chuvosa, e término em Julho, no início da seca. O tubo floral formado pelo hipanto é calcarado na base, onde se acumula o néctar produzido por nectário localizado na base do ovário. As flores são marcadamente protândricas, mas flores em diferentes fases podem ser encontradas nos racemos. Os dados mostraram que a espécie é autocompatível e não apomítica, mas devido à dicogamia marcada, necessita polinização ativa para formar frutos. Phaethornis pretrei, Amazilia fimbriata, Thalurania furcata, Eupetomena macroura e Chlorostilbon lucidus (fêmea) foram as espécies de beija-flores observadas visitando e polinizando as flores de C. melvilla. Amazilia fimbriata e C. lucidus apresentaram ocasionalmente comportamento territorial, P. pretrei apresentou forrageamento em linhas de captura, e T. furcata e E. macroura apresentaram forrageamento do tipo oportunístico, visitando as populações estudadas esporadicamente. Amazilia fimbriata, C. lucidus e P. pretrei foram considerados os polinizadores mais importantes, dada a sua constância. As características morfológicas das flores de Cuphea melvilla relacionadas a adaptações aos beija-flores parecem ser derivadas no gênero, sendo que a polinização por beija-flores nas distintas seções indica adaptação convergente a este modo de polinização.

The community of hummingbirds (Aves: Trochilidae) and the assemblage of flowers in a Caatinga vegetation

We studied hummingbirds and their food plants in an area of caatinga vegetation. We specifically examined their seasonal use of this habitat, migratory and non-migratory status, their foraging strategies and community roles The study was conducted in an area of arboreal-shrub caatinga, located in the Serra do Pará, municipality of Santa Cruz do Capibaribe, state of Pernambuco in northeastern Brazil. Field work was undertaken during 12 expeditions on a monthly basis between June, 2007 and May, 2008. Five species of hummingbirds were recorded visiting flowers in the community studied. Three were considered residents: Chlorostilbon lucidus (Shaw, 1812), Eupetomena macroura (Gmelin, 1788), and Heliomaster squamosus (Temminck, 1823). Hummingbirds visited 31 species of plants, of which only five presented attributes related to ornithophily. C. lucidus visited 29 plant species, including all ornithophilous species, and it was the most aggressive, defending territories. Among hummingbirds, C. lucidus may be considered the principal pollinator. Hummingbirds may also be acting as pollen vectors for some of the plant species not identified as ornithophilous. The hummingbird guilds varied among the plant species used as floral resources, as well as in their frequency of visits. Differences in plant species abundance, hummingbird preference, competitive exclusion or flowering seasonality are factors likely to influence those variations.

Generalised pollination system of Erythrina dominguezii (Fabaceae : Papilionoideae) involving hummingbirds, passerines and bees

Plants in the genus Erythrina are pollinated by birds, such that passerine pollination is the plesiomorphic state, whereas hummingbird pollination is the derived character. Phylogenetic studies suggest that Erythrina dominguezii belongs to a basal clade characterised as pollinated by both passerines and hummingbirds. Here, we characterise the pollination system of E. dominguezii. Floral morphology, nectar traits, breeding system, visitation rates and pollen deposition by its floral visitors were studied. Floral morphology of E. dominguezii showed traits associated with both passerine and hummingbird pollination. Nectar sugar concentration showed an intermediate value but closer to the hummingbird type; however, it was rich in hexose, which is typical of the passerine type. Approximately 5% of the flowers set fruits under free pollination. Almost 80% of recorded flowers were visited by birds, with the rest visited by hymenopterans (bumblebees and honeybees). Among avian pollinators, five species of hummingbirds and three passerine species were identified as pollinators. The hummingbird Chlorostilbon lucidus was the most efficient visitor in terms of pollen deposition and was second in frequency of visits. The passerine Icterus cayanensis was second in efficiency at depositing pollen and was the most frequent pollinator. Our results show that E. dominguezii has a generalised pollination system. In addition, we report a new case of closed flowers and secondary nectar presentation. This is the first study that compares effectiveness among different pollinators in Erythrina.

Sistemas de polinização e de reprodução de três espécies de Jatropha (Euphorbiaceae) na Caatinga, semi-árido do Brasil

The floral biology, nectar production behavior, floral visitors, and reproductive systems of Jatropha ribifolia (Pohl) Baill. (Euphorbiaceae) is presented and compared of those of J. mollissima (Pohl) Baill. and J. mutabilis (Pohl) Baill. The study was undertaken in an area of hyperxerophilous caatinga at the Estacao Biologica de Canudos, Bahia State, Brazil, from May 2005 to June 2007. The flowers of the three species are disposed in a protogynic dichasium. In J. ribifolia both staminate and pistilate flowers last for about 48 hours and flower opening is diurnal, while in J. mollissima and J. mutabilis the staminate flowers last from 12 to 15 hours and the pistilate flowers from 36 to 48 hours, with flower opening occurring at sunset. Nectar production, pollen viability, and stigma receptivity initiate soon after full opening of both floral types, and sexual activity overlaps until senescence. Nectar production varied throughout the day, with higher production by the pistilate flowers; pollen viability and stigma receptivity during the lifetime of the flower occurred in all three species. Significant differences occurred between the reproductive system treatments of J. mollissima (KW = 59.796), J. mutabilis (KW = 59.058), or J. ribifolia (KW = 63.660). The three species produced fruits by experimental geitonogamy as well as experimental xenogamy, while only J. ribifolia produced fruits by spontaneous geitonogamy. The bees Apis mellifera, Xylocopa frontalis and X. grisescens and the hummingbirds Chlorostilbon lucidus and Anopetia gounellei are potential pollinators for J. mollissima and J. mutabilis and A. mellifera and X. grisescens are potential pollinators for J. ribifolia. The diversity of anthophiles on flowers of the three species allows pollen flow and fruit set. On the other hand asynchronous flowering and differences of flower morphology and anthesis help maintain the reproductive isolation and prevent the loss of interspecific pollen due to sharing of pollinators.

Spatial analysis of sap consumption by birds in the Chaco dry forests from Argentina

Sap is a resource of high energy content that is usually inaccessible to birds, although woodpeckers have the ability to drill into living trees to obtain sap. Because spatial patterns of resource availability influence avian abundance, we explored how spatial patterns of sap availability determine the spatial distribution of two sap-feeding species in the semiarid Chaco of Argentina. We studied the White-fronted Woodpecker (Melanerpes cactorum), which obtains sap by drilling holes into tree trunks, and the Glittering-bellied Emerald (Chlorostilbon aureoventris), which can obtain sap only from active woodpecker holes; 12 other bird species also exploited the sap flows from holes drilled by White-fronted Woodpeckers. The abundance of tree species used for sap feeding did not explain the spatial patterns of territorial groups of White-fronted Woodpeckers. However, within each territory, the abundance of Woodpeckers was centred on a single tree from which sap was obtained. The abundance of the Emeralds was strongly associated with the availability of trees with active sap-holes. During the dry season, sap is a major component in the diet of White-fronted Woodpeckers and Glittering-bellied Emeralds. However, the spatial distribution of these two consumers in relation to the availability of sap was species-specific. This species-specific response was closely related to the ecology and life history of each species. The abundance of woodpeckers could be determined by local mechanisms, such as location of a single sap tree in their small territories, whereas non-territorial hummingbirds would be able to track sap wells at a larger scale than the territory of a single territorial group of Woodpeckers. Our results show the importance of spatial analysis in identifying the ecological determinant of habitat selection and niche differentiation within species.

The hummingbird community and their floral resources in an urban forest remnant in Brazil

The temporal and spatial resource use among hummingbirds was studied over 13 months in an urban forest remnant (Prosa State Park: PSP) in Campo Grande, Mato Grosso do Sul, Brazil. Hummingbird visitation was recorded at three ornithophilous and eleven non-ornithophilous species. Flower density was roughly constant during the study period, with the density of non-ornithophilous flowers being higher than that of ornithophilous ones. Mean values of nectar volume and concentration were similar between ornithophilous and non-ornithophilous species. Eight hummingbird species were observed at PSP: Amazilia fimbriata, Anthracothorax nigricollis, Chlorostilbon lucidus, Eupetomena macroura, Hylocharis chrysura, Florisuga fusca, Thalurania furcata and an unidentified species. Hummingbird visit frequencies to ornithophilous and non-ornithophilous flowers were similar. However, some non-ornithophilous species received a higher number of visits, which seems to be related to their large number of open flowers per plant per day. The number of feedings bouts of hummingbirds increased with the total number of flowers observed per focal plant. All recorded species of hummingbirds visited non-ornithophilous flowers, predominantly melittophilous and generalised entomophilous flowers. Hummingbird species recorded at PSP may be viewed as generalists, visiting a large number of non-ornithophilous species. Despite being an urban forest, PSP is relatively rich in hummingbird species, suggesting that it provides important shelter and foraging sites for hummingbirds in such an environment.

Relationship between floral traits and floral visitors in two coexisting Tecoma species (Bignoniaceae)

In this paper, we studied the floral biology of Tecoma fulva ssp. garrocha and T. stans in Vaqueros (Salta, Argentina), where both species coexist. We tested the idea that floral traits are associated with the pollinator types that visit them. According to our results, T. fulva ssp. garrocha presented traits common to bird flowers and were visited by two species of Trochilidae (Colibri serrirostris and Chlorostilbon lucidus). In addition, T. stans exhibited traits common to hymenoptera flowers and were visited principally by Apis mellifera and Bombus atratus. This study showed that floral traits are predictive of animal visitors.

Beija-flores (Aves: Trochilidae) e seus recursos florais em uma área de caatinga da Chapada Diamantina, Bahia, Brasil

This study investigated the species of hummingbird occurring in an area of caatinga vegetation, examining their seasonal activities, the assemblages of plants that they used, as well as the floral characteristics and flowering phenology of that vegetation. These surveys were performed in an area of arboreal caatinga in Chapada Diamantina, municipality of Mucuge, state of Bahia, Brazil, during 12 expeditions undertaken on a bi-monthly basis between October, 2005 and August, 2007. Field activities included observations made of the visiting hummingbird species, their behavior, and the frequency of their visits; as well as the plant species visited, their floral attributes, size, and the flowering phenophase evident on the occasion of each expedition. Seven species of hummingbirds were registered, including five residents. Phaethornis pretrei (Lesson & Delattre, 1839) acted as the organizer of this pollination guild. This species and Chlorostilbon lucidus (Shaw, 1812), these two species were considered the principal pollinators within the community. The hummingbirds visited a total of 29 plant species, of which only 12 are considered ornitophilous. The plant community presented a continuous flowering, with 19 species flowering in both the dry and the rainy season, permitting the year-round permanence of resident hummingbird species.

Fenologia e visitantes florais de Erythrina crista-galli L. (Leguminosae: Faboideae) em Santa Maria, Rio Grande do Sul, Brasil

Phenology and fl oral visitors of Erythrina crista-galli L. (Leguminosae: Faboideae) in Santa Maria, Rio Grande do Sul, Brazil. Erythrina crista- galli is a characteristic species of the Pampa biome also used as an ornament in urban arborization. Erythrina crista-galli fl ourishes more intensively from November to December. Anthesis starts around 7:00 am to 11:00 am, and fl owers last fi ve days. A total of 1,275 fl oral visits were registered over 57h of observations. Apidae bees (Trigona spinipes and Apis mellifera) were the most frequent visitors (88.23%), followed by Muscidae fl ies (5.50%), Formicidae ants (2.35%), Ves- pidae wasps (1.56%), and Chrysomelidae beetles (1.56%). Trochilidae hummingbirds (Chlorostilbon aureoventris) (0.79%) also visited the fl owers. Trigona spinipes was observed at throughout the daytime and behaved as a probable pollinator, along with A. mellifera and C. aureoventris. E. crista-galli is autocompatible, producing fruits and seeds after manual pollination and under natural conditions.