ABSTRACT
Context-dependence in mutualisms is a fundamental aspect of ecological interactions. Within plant-ant mutualisms, particularly in terms of biotic protection and pollination, research has predominantly focused on elucidating the benefits while largely overlooking potential costs. This notable gap underscores the need for investigations into the drawbacks and trade-offs associated with such mutualistic relationships. Here, we evaluated the role of pericarpial nectaries (PNs) in shaping the dynamics of ant-pollinator mutualisms. Specifically, we investigated whether ants visiting the PN of Palicourea rigida (Rubiaceae) could deter hummingbirds and disrupt pollination, ultimately influencing fruit production. Our research involved manipulative experiments and observation of ant-pollinator interactions on P. rigida plants in the Brazilian savannah. We found that visiting ants can deter hummingbirds and/or disrupt pollination in P. rigida, directly influencing fruit set. However, these results are species-specific. The presence of very aggressive, large predatory ants, such as E. tuberculatum, had a negative impact on hummingbird behavior, whereas aggressive mid-sized ants, such as C. crassus, showed no effects. Our study illuminates the multifaceted aspects of ant-plant mutualisms and underscores the importance of evaluating costs and unexpected outcomes within these ecological relationships.
ABSTRACT
Most eulophid wasps are primary parasitoids, mainly of endophytic insect larvae (Diptera, Coleoptera, Lepidoptera, Hymenoptera, Hemiptera, and Thysanoptera), but can also attack spider eggs, gall-forming mites, or nematodes. A few species are known to parasitize ants. Here we report on the occurrence of Horismenus floridensis (Schauff and Boucek) attacking Camponotus atriceps (Smith) in southern Mexico (Campeche), expanding the distribution for this eulophid species and the range of its potential hosts. We also provide an updated list of the Horismenus Walker species found in Mexico, which currently includes 21 identified species. This is the second host ant ever recorded for H. floridensis and the first reliable record of C. atriceps as a host for this eulophid wasp. The first host ant reported from Florida 35 years ago was the closely related valid species, C. floridanus (Buckley), erroneously synonymized at that time with C. atriceps (formerly, C. abdominalis (Fabricius)).
Subject(s)
Ants , Coleoptera , Hymenoptera , Wasps , Animals , Mexico , Insecta , Host-Parasite InteractionsABSTRACT
Plants provide extrafloral nectar, which is a food resource taken by ants, especially aggressive species that may act as plant guards. To our knowledge, no study has been conducted to concurrently investigate the fluctuation of plant fitness over its whole reproductive season, recording and comparing both short periods (different samplings during the plant's reproductive season) and the season/pooled data (all fruits produced during the reproductive season). Here, by assigning plants to either ant-present or absent treatments, we investigated the influence of the protective foliage-dwelling ant, Camponotus crassus, on the flower bud and fruit production of four extrafloral nectaried plants (Ancistrotropis firmula, Bionia coriacea, Cochlospermum regium, and Peixotoa tomentosa) throughout their annual reproductive season. Periodic samples in the field revealed a large variation in plant reproduction throughout the season; the increases in buds and fruits were not constantly higher in plants with ants, and in fact, plants without ants had more reproductive structures sometimes. Nonetheless, the examination of the pooled data, i.e., cumulative number of flower buds and fruits produced during the reproductive season, revealed the plants with ants produced more flower buds and fruits (e.g., up to two-fold greater in A. firmula) compared to ant-absent treatments. Our results indicate the effects of ants on plant reproduction are not constant over time, but the net benefits to plants with ants are reflected in increased fruit production. Therefore, the investigations of the benefit of ants on plants should consider the whole plant's reproductive season rather than single samplings within plant reproduction period.
Subject(s)
Ants , Animals , Plant Nectar , Plants , Seasons , SymbiosisABSTRACT
BACKGROUND AND AIMS: Eriocaulaceae exhibit a great variety of floral traits associated with insect (e.g. nectariferous structures) and wind pollination (unisexual flowers, exposed sexual organs and small pollen grains), as well as the 'selfing syndrome' (small flowers, short distance between stigma and anthers, and temporal overlap of male and female phases). Paepalanthus bifidus, P. subtilis and P. tortilis are related species that differ in form, size and colour of floral structures. We aimed to investigate the pollination and reproductive biology of these three species. METHODS: We analysed the floral biology, floral visitors, pollinator behaviour, and the contribution of insects, wind and spontaneous geitonogamy to fruit set. We also evaluated the floral colour and scent of the species. Colour reflectance of capitula of each species was measured and plotted in models of insect vision. Floral scent samples were extracted and the compounds were compared to vegetative scent samples. KEY RESULTS: In all species, the staminate and pistillate flowers are arranged in alternating cycles with a temporal overlap between these phases. Ants were the most frequent floral visitors and were effective pollinators in P. bifidus and P. tortilis, while flies were occasional pollinators in P. tortilis. Floral visitors were not observed in P. subtilis. In all species, fruits were produced by spontaneous geitonogamy, with no evidence of wind pollination. According to the models of insect vision, the colours of the capitula of P. bifidus and P. subtilis are the most inconspicuous for ants and flies. We found no difference between the emission of volatiles of inflorescences and vegetative structures. CONCLUSIONS: This study suggests that ant pollination might be more widespread in Eriocaulaceae than currently assumed. Furthermore, for small monocarpic plants, mixed mating strategies are most favourable, by ensuring reproduction either by outcrossing when pollinators are abundant or by spontaneous geitonogamy when pollinations are scarce/absent.
Subject(s)
Ants , Eriocaulaceae , Animals , Flowers/chemistry , Insecta , Pollination , ReproductionABSTRACT
BACKGROUND: Ant-plant mutualistic networks tend to have a nested structure that contributes to their stability, but the ecological factors that give rise to this structure are not fully understood. Here, we evaluate whether ant abundance and dominance hierarchy determine the structure of the ant-plant networks in two types of vegetation: oak and grassland, in two temperate environments of Mexico: Flor del Bosque State Park (FBSP) and La Malinche National Park (MNP). We predicted that dominant and abundant ant species make up the core, and submissives, the periphery of the network. We also expected a higher specialization level in the ant trophic level than in plant trophic level due to competition among the ant species for the plant-derived resources. METHODS: The ant-plant interaction network was obtained from the frequency of ant-plant interactions. We calculated a dominance hierarchy index for the ants using sampling with baits and evaluated their abundance using pitfall traps. RESULTS: In MNP, the Formica spp. species complex formed the core of the network (in both the oak forest and the grassland), while in FBSP, the core species were Prenolepis imparis (oak forest) and Camponotus rubrithorax (grassland). Although these core species were dominant in their respective sites, they were not necessarily the most dominant ant species. Three of the four networks (oak forest and grassland in FBSP, and oak forest in MNP) were nested and had a higher number of plant species than ant species. Although greater specialization was observed in the ant trophic level in the two sites and vegetations, possibly due to competition with the more dominant ant species, this was not statistically significant. In three of these networks (grassland and oak forest of MNP and oak forest of FBSP), we found no correlation between the dominance hierarchy and abundance of the ant species and their position within the network. However, a positive correlation was found between the nestedness contribution value and ant dominance hierarchy in the grassland of the site FBSP, which could be due to the richer ant-plant network and higher dominance index of this community. CONCLUSIONS: Our evidence suggests that ant abundance and dominance hierarchy have little influence on network structure in temperate ecosystems, probably due to the species-poor ant-plant network and a dominance hierarchy formed only by the presence of dominant and submissive species with no intermediate dominant species between them (absence of gradient in hierarchy) in these ecosystems.
ABSTRACT
Myrmecotypus tahyinandu sp. n. is described from the Bolivian Chiquitano forest, and M. niger Chickering, 1937 is recorded from Bolivia for the first time. The morphological differentiation among the closely related M. tahyinandu sp. n. and M. iguazu Rubio Arbino, 2009 is likely attributable to the selection for specific ant mimicry. Adults of M. tahyinandu sp. n. are accurate mimics of the ant Camponotus crassus Mayr, 1862, M. iguazu of C. sericeiventris (Guérin-Méneville, 1838), and M. niger of Dolichoderus bispinosus (Olivier, 1792). This study is the first to identify ant models for morphologically closely related Castianeirinae, providing a promising starting point for future research on ant mimicry.
Subject(s)
Ants , Spiders , Animals , NigerABSTRACT
BACKGROUND AND AIMS: Ant-plant associations are widely diverse and distributed throughout the world, leading to complex ecological networks. Regarding ant-plant mutualism, ant pollination is a very rare interaction and few studies have shown the role of ants as pollinators. Therefore, we aimed to evaluate the role of ants as effective pollinators of Paepalanthus lundii (Eriocaulaceae) in a Brazilian savanna. METHODS: Fieldwork with experimental manipulation was conducted to evaluate the fitness of P. lundii, considering potential pollinators. For this, we mainly observed the number of seeds produced in different conditions: control, ant exclusion, exclusion of flying insects, and exclusion (entomophily test) of both ants and flying insects. Furthermore, we evaluated all floral visitors throughout the day, stigma receptivity, the numbers of male and female flowers, and patterns of species co-occurrence, which can indicate the presence of different pollinators in the plants at the same time. KEY RESULTS: We observed a relation between seed production and ant visits; Camponotus crassus was the most frequent floral visitor and the most effective pollinator. Also, we observed a statistical difference between the numbers of male and female flowers produced, with a greater number of male flowers. Furthermore, P. lundii presented flowering asynchrony, with 12 different types of maturation sequence, which indicates a cross-pollination system. Lastly, we observed an overlap of the greatest abundance of C. crassus and the time of plant stigmatic receptivity, and a pattern of non co-occurrence of ants, which shows the pollinator role of this ant. CONCLUSIONS: Our data provide evidence that previous generalizations neglecting the importance of ants as pollinators are wrong. Brazilian savanna can reveal a lot about the ant-pollination syndrome, since this environment presents peculiar characteristics related to this association. Thus, this study has great significance for the understanding of the ant-pollination syndrome, and for the understanding of the complex ecological networks present in these dry arid systems.
Subject(s)
Ants , Eriocaulaceae , Animals , Brazil , Female , Flowers , Grassland , PollinationABSTRACT
Camponotus (Formicinae) is the most specious and abundant genus of the family Formicidae. The genus is represented by ants that both forage and nest in the most diverse terrestrial and arboreal environments. Among the arboreal species of Camponotus are those of the subgenus Dendromyrmex. We recorded, for the first time, evidence of Camponotus chartifex (Smith, 1860) in the state of Mato Grosso, Brazil, and expanded the distributions of Camponotus nidulans (Smith, 1860) and Camponotus apicalis (Mann, 1916). We include information on the biology of the species and a discussion on the sampling of arboreal and winged ants.(AU)
Camponotus é um dos gêneros mais especiosos e abundantes da subfamília Formicidae. O gênero é representado por formigas que se alimentam e nidificam nos mais diversos habitats de ambientes terrestres e arbóreos. Entre as espécies arborícolas de Camponotus, estão as do subgênero Dendromyrmex. Registramos, pela primeira vez, Camponotus chartifex (Smith, 1860) para o estado de Mato Grosso, Brasil, e expandimos a distribuição de Camponotus nidulans (Smith, 1860) e Camponotus apicalis (Mann, 1916), incluindo informações biológicas sobre as espécies e uma discussão sobre a amostragem de formigas arborícolas e aladas.(AU)
ABSTRACT
Camponotus (Formicinae) is the most specious and abundant genus of the family Formicidae. The genus is represented by ants that both forage and nest in the most diverse terrestrial and arboreal environments. Among the arboreal species of Camponotus are those of the subgenus Dendromyrmex. We recorded, for the first time, evidence of Camponotus chartifex (Smith, 1860) in the state of Mato Grosso, Brazil, and expanded the distributions of Camponotus nidulans (Smith, 1860) and Camponotus apicalis (Mann, 1916). We include information on the biology of the species and a discussion on the sampling of arboreal and winged ants. (AU)
Camponotus é um dos gêneros mais especiosos e abundantes da subfamília Formicidae. O gênero é representado por formigas que se alimentam e nidificam nos mais diversos habitats de ambientes terrestres e arbóreos. Entre as espécies arborícolas de Camponotus, estão as do subgênero Dendromyrmex. Registramos, pela primeira vez, Camponotus chartifex (Smith, 1860) para o estado de Mato Grosso, Brasil, e expandimos a distribuição de Camponotus nidulans (Smith, 1860) e Camponotus apicalis (Mann, 1916), incluindo informações biológicas sobre as espécies e uma discussão sobre a amostragem de formigas arborícolas e aladas.(AU)
Subject(s)
Ants/classification , Animal Distribution/classification , Species Specificity , Brazil , Amazonian EcosystemABSTRACT
The phytotelm-dwelling frogs from the genus Phyllodytes Wagler, 1830 have been characterized as specialist frogs regarding their diet strategy which is mainly composed by colonial insects. Herein, we used two species of ants (Camponotus sp. and Gnamptogenys sp. with distinct defensive mechanisms to test the predatory behavior of Phyllodytes luteolus Wied, 1824. The experiment was conducted with frogs inhabiting a patch of 20 bromeliads (Aechmea cf. blanchetiana). Ants were offered randomly to the frogs until we obtained ten observations of predation of each ant species. We observed and recorded the time that P. luteolus needed to keep each ant species inside its mouth before it could ingest it. Predatory behavior was highly distinct. While Camponotus were caught and swallowed within six seconds and without apparent discomfort, individuals of P. luteolus had more difficulty in swallowing Gnamptogenys individuals, the time of manipulation ranging from 57 to 177 seconds. The mean values of time of predation observed in each treatment was highly significant (p<0.001). We conclude that differences found in the time of manipulation are highly correlated with defense mechanisms of each species of ants.(AU)
As pererecas que habitam fitotelmatas do gênero Phyllodytes Wagler, 1830 têm sido caracterizadas como especialistas em relação à sua estratégia de dieta, que é composta principalmente por insetos coloniais. Neste trabalho, usamos duas espécies de formigas (Camponotus sp. e Gnamptogenys sp.) com mecanismos de defesa diferentes para testar o comportamento predatório de Phyllodytes luteolus Wied, 1824. O experimento foi conduzido com pererecas que habitavam uma mancha de 20 bromélias (Aechmea cf. blanchetiana ). As formigas foram oferecidas aleatoriamente para as pererecas até que obtivemos dez observações de predação para cada espécie de formiga. Observamos e registramos o tempo que P. luteolus precisou manter cada espécie de formiga dentro da boca antes da mesma poder ser ingerida. O comportamento de predação foi altamente distinto. Enquanto Camponotusforam capturadas e engolidas dentro de seis segundos e sem desconforto aparente, indivíduos de P. luteolus tiveram maiores dificuldades em engolir indivíduos de Gnamptogenys, com tempo de manipulação variando de 57 a 177 segundos. Os valores médios do tempo de predação em cada tratamento foram altamente significativos (p<0.001). Concluímos que as diferenças encontradas no tempo de manipulação estão altamente correlacionadas com os mecanismos de defesa de cada espécie de formiga.(AU)
Subject(s)
Animals , Anura , Ants , Predatory Behavior , Behavior, Animal , BromeliaABSTRACT
The phytotelm-dwelling frogs from the genus Phyllodytes Wagler, 1830 have been characterized as specialist frogs regarding their diet strategy which is mainly composed by colonial insects. Herein, we used two species of ants (Camponotus sp. and Gnamptogenys sp. with distinct defensive mechanisms to test the predatory behavior of Phyllodytes luteolus Wied, 1824. The experiment was conducted with frogs inhabiting a patch of 20 bromeliads (Aechmea cf. blanchetiana). Ants were offered randomly to the frogs until we obtained ten observations of predation of each ant species. We observed and recorded the time that P. luteolus needed to keep each ant species inside its mouth before it could ingest it. Predatory behavior was highly distinct. While Camponotus were caught and swallowed within six seconds and without apparent discomfort, individuals of P. luteolus had more difficulty in swallowing Gnamptogenys individuals, the time of manipulation ranging from 57 to 177 seconds. The mean values of time of predation observed in each treatment was highly significant (p<0.001). We conclude that differences found in the time of manipulation are highly correlated with defense mechanisms of each species of ants.
As pererecas que habitam fitotelmatas do gênero Phyllodytes Wagler, 1830 têm sido caracterizadas como especialistas em relação à sua estratégia de dieta, que é composta principalmente por insetos coloniais. Neste trabalho, usamos duas espécies de formigas (Camponotus sp. e Gnamptogenys sp.) com mecanismos de defesa diferentes para testar o comportamento predatório de Phyllodytes luteolus Wied, 1824. O experimento foi conduzido com pererecas que habitavam uma mancha de 20 bromélias (Aechmea cf. blanchetiana ). As formigas foram oferecidas aleatoriamente para as pererecas até que obtivemos dez observações de predação para cada espécie de formiga. Observamos e registramos o tempo que P. luteolus precisou manter cada espécie de formiga dentro da boca antes da mesma poder ser ingerida. O comportamento de predação foi altamente distinto. Enquanto Camponotusforam capturadas e engolidas dentro de seis segundos e sem desconforto aparente, indivíduos de P. luteolus tiveram maiores dificuldades em engolir indivíduos de Gnamptogenys, com tempo de manipulação variando de 57 a 177 segundos. Os valores médios do tempo de predação em cada tratamento foram altamente significativos (p<0.001). Concluímos que as diferenças encontradas no tempo de manipulação estão altamente correlacionadas com os mecanismos de defesa de cada espécie de formiga.
Subject(s)
Animals , Anura , Behavior, Animal , Predatory Behavior , Ants , BromeliaABSTRACT
ABSTRACT The phytotelm-dwelling frogs from the genus Phyllodytes Wagler, 1830 have been characterized as specialist frogs regarding their diet strategy which is mainly composed by colonial insects. Herein, we used two species of ants (Camponotus sp. and Gnamptogenys sp.) with distinct defensive mechanisms to test the predatory behavior of Phyllodytes luteolus Wied, 1824. The experiment was conducted with frogs inhabiting a patch of 20 bromeliads (Aechmea cf. blanchetiana). Ants were offered randomly to the frogs until we obtained ten observations of predation of each ant species. We observed and recorded the time that P. luteolus needed to keep each ant species inside its mouth before it could ingest it. Predatory behavior was highly distinct. While Camponotus were caught and swallowed within six seconds and without apparent discomfort, individuals of P. luteolus had more difficulty in swallowing Gnamptogenys individuals, the time of manipulation ranging from 57 to 177 seconds. The mean values of time of predation observed in each treatment was highly significant (p 0.001). We conclude that differences found in the time of manipulation are highly correlated with defense mechanisms of each species of ants.
RESUMO As pererecas que habitam fitotelmatas do gênero Phyllodytes Wagler, 1830 têm sido caracterizadas como especialistas em relação à sua estratégia de dieta, que é composta principalmente por insetos coloniais. Neste trabalho, usamos duas espécies de formigas (Camponotus sp. e Gnamptogenys sp.) com mecanismos de defesa diferentes para testar o comportamento predatório de Phyllodytes luteolus Wied, 1824. O experimento foi conduzido com pererecas que habitavam uma mancha de 20 bromélias (Aechmea cf. blanchetiana ). As formigas foram oferecidas aleatoriamente para as pererecas até que obtivemos dez observações de predação para cada espécie de formiga. Observamos e registramos o tempo que P. luteolus precisou manter cada espécie de formiga dentro da boca antes da mesma poder ser ingerida. O comportamento de predação foi altamente distinto. Enquanto Camponotus foram capturadas e engolidas dentro de seis segundos e sem desconforto aparente, indivíduos de P. luteolus tiveram maiores dificuldades em engolir indivíduos de Gnamptogenys, com tempo de manipulação variando de 57 a 177 segundos. Os valores médios do tempo de predação em cada tratamento foram altamente significativos (p 0.001). Concluímos que as diferenças encontradas no tempo de manipulação estão altamente correlacionadas com os mecanismos de defesa de cada espécie de formiga.
ABSTRACT
The syrphid subfamily Microdontinae is characterized by myrmecophily of their immature stages, i.e., they develop in ant nests. Data on natural history of microdontines are scarce, especially in the Neotropics. Based on fieldwork in southern Brazil, this study provided new data on development and ecology of the hoverfly Pseudomicrodon biluminiferus (Hull) (Diptera: Syrphidae) as well as the first morphological descriptions of male genitalia, larvae, and pupa. Immature specimens were specifically found in colonies of the ant species Crematogaster limata Smith (Hymenoptera: Formicidae) found in rosettes of the bromeliad species Aechmea lindenii (E. Morren) Baker (Poales: Bromeliaceae) and A. nudicaulis (L.) Grisebach. Third instar larvae were observed preying on ant larvae, revealing the parasitic nature of P. biluminiferus. In this and several other aspects, the natural history of P. biluminiferus is similar to that of Holarctic microdontine species. Exceptions include: (i) indications that adults of P. biluminiferus outlast the winter months (in contrast to 3(rd)instar larvae in Holarctic species) and (ii) P. biluminiferus' relationship with bromeliads. The importance of bromeliads for this host-parasite system is evaluated in this paper. The single occurrence of another, unidentified microdontine species' pupae in a nest of the ant species Camponotus melanoticus Emery (Hymenoptera: Formicidae) is reported.
Subject(s)
Ants/parasitology , Diptera/physiology , Animals , Brazil , Bromeliaceae/growth & development , Diptera/anatomy & histology , Diptera/growth & development , Female , Larva/anatomy & histology , Larva/growth & development , Larva/parasitology , Larva/physiology , Male , Pupa/anatomy & histology , Pupa/growth & development , Pupa/parasitology , Pupa/physiology , SeasonsABSTRACT
Ant gardens are a special association type between ants and epiphytes, in which two or more ant species can share the same nest in a parabiotic relationship. This association that occurs in tropical forests is still poorly understood. The aim of this study was to evaluate ants gardens in the Central Amazon and to determine if ants identify and remove potential herbivores that are visiting the host tree of ants gardens occupied by the species Camponotus femoratus and Crematogaster levior. In this study, it was observed 42 trees occupied by ants gardens. In each tree it was inserted a termite as bait at different distances from the nest, the time of the termites' removal was recorded and it was observed if there was the need of assistance from other ants to perform the removal of the bait. The results revealed that both species examined the tree host to forage. During the capture of the bait, C. levior was more efficient to detect the termite, and it was not observed the need of recruits to carry it to the nest. In some cases, individuals of de C. femoratus identified the bait and individuals of C. levior carried to the nest. The relationship between the host tree and ants is beneficial to both of them, since the tree receives indirect protection against termites and gives support to the ants nest.(AU)
Jardins de formigas são um tipo especial de associação entre formigas e epífitas, em que duas ou mais espécies de formigas podem compartilhar o mesmo ninho por parabiose. Essa associação que ocorre em florestas tropicais ainda foi pouco estudada. O objetivo deste trabalho foi avaliar jardins de formigas na Amazônia Central determinando se as formigas identificam e removem potenciais herbívoros que estejam visitando as árvores hospedeiras de jardins de formigas ocupados pelas espécies Camponotus femoratus e Crematogaster levior. No estudo foram observadas 42 árvores contendo jardins de formigas. Em cada árvore foi colocado um cupim, como isca, a diferentes distâncias do ninho, contabilizado o tempo para sua remoção e observado se havia recrutamento de outras formigas para realizar a remoção da isca. Os resultados evidenciaram que ambas as espécies examinam as árvores hospedeiras para forragear. Durante a captura da isca, C. levior foi mais eficiente para detectar o cupim, não tendo sido observado recrutamento para carregá-lo ao ninho. Em alguns casos, indivíduos de C. femoratus identificaram a isca e indivíduos de C. levior a carregaram ao ninho. A relação entre árvore hospedeira e formigas beneficiam ambas, pois a árvore recebe proteção indireta contra cupins e fornece apoio para o ninho das formigas.(AU)
ABSTRACT
Ant gardens are a special association type between ants and epiphytes, in which two or more ant species can share the same nest in a parabiotic relationship. This association that occurs in tropical forests is still poorly understood. The aim of this study was to evaluate ants gardens in the Central Amazon and to determine if ants identify and remove potential herbivores that are visiting the host tree of ants gardens occupied by the species Camponotus femoratus and Crematogaster levior. In this study, it was observed 42 trees occupied by ants gardens. In each tree it was inserted a termite as bait at different distances from the nest, the time of the termites' removal was recorded and it was observed if there was the need of assistance from other ants to perform the removal of the bait. The results revealed that both species examined the tree host to forage. During the capture of the bait, C. levior was more efficient to detect the termite, and it was not observed the need of recruits to carry it to the nest. In some cases, individuals of de C. femoratus identified the bait and individuals of C. levior carried to the nest. The relationship between the host tree and ants is beneficial to both of them, since the tree receives indirect protection against termites and gives support to the ants nest.
Jardins de formigas são um tipo especial de associação entre formigas e epífitas, em que duas ou mais espécies de formigas podem compartilhar o mesmo ninho por parabiose. Essa associação que ocorre em florestas tropicais ainda foi pouco estudada. O objetivo deste trabalho foi avaliar jardins de formigas na Amazônia Central determinando se as formigas identificam e removem potenciais herbívoros que estejam visitando as árvores hospedeiras de jardins de formigas ocupados pelas espécies Camponotus femoratus e Crematogaster levior. No estudo foram observadas 42 árvores contendo jardins de formigas. Em cada árvore foi colocado um cupim, como isca, a diferentes distâncias do ninho, contabilizado o tempo para sua remoção e observado se havia recrutamento de outras formigas para realizar a remoção da isca. Os resultados evidenciaram que ambas as espécies examinam as árvores hospedeiras para forragear. Durante a captura da isca, C. levior foi mais eficiente para detectar o cupim, não tendo sido observado recrutamento para carregá-lo ao ninho. Em alguns casos, indivíduos de C. femoratus identificaram a isca e indivíduos de C. levior a carregaram ao ninho. A relação entre árvore hospedeira e formigas beneficiam ambas, pois a árvore recebe proteção indireta contra cupins e fornece apoio para o ninho das formigas.
ABSTRACT
Ants are highly abundant in neotropical regions, with certain species adapted to the urban environment, where they can cause damage to human health. The main method for controlling ants consists of using organosynthetic insecticides, which are potentially toxic to the environment. Essential plant oils are considered a viable alternative to the use of conventional insecticides. In this study, we analyze the bioinsecticidal activity and repellence of patchouli essential oil (Pogostemon cablin) against three species of urban ants: Camponotus melanoticus, Camponotus novograndensis, and Dorymyrmex thoracicus. The chemical composition of the essential oil was analyzed by GC-MS and GC-FID. The major compounds were patchoulol (36.6%) followed by α-bulnesene (13.95%), and α-guaiene (11.96%). Toxicity and repellency bioassays were performed using the essential oil over the ants, and mortality evaluations were performed at 4, 24, and 48 h after performing the bioassays. Mortality percentage of the ants on 7 µg/mg was on average 84%. The essential oil of P. cablin displayed toxicity against all three species of urban ants, with the lowest LD50 being observed for D. thoracicus (2.02 µg oil/mg insect) after 48 h of exposure compared to C. melanoticus (2.34 µg oil/mg insect) and C. novogranadensis (2.95 µg oil/mg insect). The essential oil of P. cablin was strongly repellent to the three species of ants in all concentrations tested (0.01% and 1% v/v). Considering the potential toxicity and repellency of the P. cablin essential oil to the urban ants, future studies could investigate the practical application of this oil to control of this insects.
Subject(s)
Ants/drug effects , Insect Repellents/pharmacology , Insecticides/pharmacology , Lamiaceae/chemistry , Oils, Volatile/pharmacology , Plant Oils/pharmacology , Animals , Biological Assay , Insect Repellents/chemistry , Insecticides/chemistry , Oils, Volatile/chemistry , Plant Oils/chemistry , Time FactorsABSTRACT
Although Merostachys fischeriana is very abundant in the Brazilian Atlantic Rainforest, little attention has been paid to the biological interactions with other animals. The present study describes some of the interactions between ants and this bamboo species. The experiment was carried out in a fragment of a montane tropical forest in the Parque Estadual do Itacolomi, near Ouro Preto, MG, Brazil. Thirty culms of bamboo were randomly collected. The ants were obtained by direct collection from nodes and internodes. Morphometric variables of the bamboo were recorded for characterization of potential ant habitat. Merostachys fischeriana grows in rosettes as a thin bamboo (average = 1,0 cm; se = 0,27; n = 20) and is tall enough to reach the upper canopy of this low forest (average = 9,1 m; se = 2,72; n = 20). Fifteen ant species were sampled. Brachymyrmex heeri Forel was the most abundant in the nodes, while Camponotus crassus Mayr (Hymenoptera: Formicidae) was the most abundant in the internodes. The composition of the species that inhabit the internodes was different from the composition in the node (Q-test: Q = 3,76; P = 0,05). The level of occupation was defined by the number of holes (F = 10,33; P < 0,01), the number of internodes in the canopy (F = 6,84; P = 0,01) and the length of the culm (F = 7,52; P = 0,01). The plant's morphology allowed the occurrence of additional species of ants in the canopy and influenced the composition of the entire ant assemblage.
Subject(s)
Animals , Ants , Bambusa , Ecosystem , Trees , Brazil , Nesting BehaviorABSTRACT
Many ant species displaying synanthropic behavior that have successfully dispersed in urban areas can cause problems in hospitals by acting as bacterial vectors. In this study, we encountered bacteria on ants collected at the Universidade Federal de Uberlândia hospital, in the campus and at households nearby. The ants were identified as Tapinoma melanocephalum (Fabricius) and Camponotus vittatus (Forel) (Hymenoptera: Formicidae) and the bacterial strains found here belong to the group of the coagulase-positive staphylococcus, coagulase-negative staphylococcus and gram negative bacilli, including antimicrobial drug-resistant strains. An investigation of the bacteria found in the ants and in the environment revealed that some ants carried non-isolated bacteria from the same environment and with high levels of resistance, evidencing the transmission potential of these insects.
Muitas espécies de formigas de comportamento sinantrópico que tiveram sucesso na dispersão em áreas urbanas podem causar problemas em hospitais ao atuarem como vetoras, transportando bactérias. Neste estudo, foram encontradas bactérias em formigas coletadas no Hospital de Clínicas da Universidade Federal de Uberlândia, no campus e em residências próximas. As formigas coletadas foram identificadas como Tapinoma melanocephalum (Fabricius) e Camponotus vittatus (Forel) (Hymenoptera: Formicidae) e as cepas bacterianas encontradas pertenciam ao grupo dos estafilococos coagulase positivos, estafilococos coagulase negativos e bacilos gram negativos, tendo sido encontradas cepas resistentes a antimicrobianos. O estudo de bactérias encontradas nas formigas e no ambiente mostrou que algumas formigas carreavam bactérias não isoladas do mesmo ambiente e com níveis de resistência mais elevados, evidenciando o potencial transmissor desses insetos.
Subject(s)
Animals , Ants/microbiology , Bacteria/isolation & purification , Disease Vectors , Cross Infection/microbiology , Urban HealthABSTRACT
Soft scale insects of the genus Cryptostigma Ferris (Coccidae: Myzolecaniinae) occur only in the Neotropical region and usually live in the nests of ants, or rarely bees, inside plant stems, or feed on plant roots. Here we provide the first report of Cryptostigma from Peru. We describe Cryptostigma guadua sp.n. based on the adult female and the first-instar nymph. These coccids have been collected only from the nests of Camponotus (Myrmostenus) longipilis Emery, C. (Myrmostenus) mirabilis Emery and Camponotus (Pseudocolobopsis) sp. (Formicidae: Formicinae) from inside live bamboos of Guadua sp. (Poaceae) in lowland tropical forest in Parque Nacional del Manu, in southeast Peru. The adult female and the first-instar nymph (crawler) of C. guadua sp. n. are compared to closely related species.
Os coccídeos do gênero Cryptostigma Ferris (Coccidae: Myzolecaniinae) ocorrem somente na região Neotropical e normalmente vivem em ninhos de formigas, ou raramente de abelhas, dentro de troncos, ou raízes de plantas. Neste trabalho, descreve-se pela primeira vez uma espécie de Cryptostigma coletada no Peru. A descrição de Cryptostigma guadua sp.n. é baseada na fêmea adulta e em ninfas do primeiro ínstar. Foram coletados em ninhos de Camponotus (Myrmostenus) longipilis Emery, C. (Myrmostenus) mirabilis Emery e Camponotus (Pseudocolobopsis) sp. (Formicidae: Formicinae), encontrados dentro de bambus vivos do gênero Guadua (Poaceae) planície de mata tropical do Parque Nacional del Manu, no sudeste do Peru. A fêmea adulta e a ninfa do primeiro ínstar de C. guadua sp.n. são comparadas com outras espécies próximas na taxonomia do grupo.
ABSTRACT
1) When a thermal gradient (20-40° C) was established along a laboratory nest, Camponotus mus nurse workers showed a photoperiodic circadian rhythm of temperature preferences for brood rearing. Two different temperatures were daily selected to translocate the brood, i.e. 30.8° C selected at the middle of the photophase, and 27.5° C selected during the scotophase, 8 h later. 2) The daily temperature response of nurse workers consisted of paired high and low-temperature translocations, with a 8 hs-interval in between: high-temperature translocation was shown to be entrained by the photophase length, whereas low-temperature translocation was shown to be dependent on the precedent one. 3) Prey deprivation to the colony modified the brood transport behaviors resulting in translocations of only cocoons and large (ripe) larvae, stages in which the pupation processes are triggered. Small larvae and eggs remained located at 27.5° C. 4) Evaluation of pupa developmental time as well as percentage of pupa mortality at different temperature regimes allowed to construct an efficiency index relating pupa survival and cocoon developmental time. In the range of temperatures selected by nurses, the index reached its maximal values. 5) The ecological significance of these results is discussed.