The present study aimed to record all flower visitors of Aechmea nudicaulis (Bromeliaceae) and their foraging behavior as well as their role in animal–plant and animal–animal relationships, and to assess temporal pattern of visitation on flowers. In order to estimate the influence of habitat on species richness and abundance, we compared the diversity and visitation frequency of flower visitors to Ae. nudicaulis in three different habitat types – secondary forest, low and high vegetation restinga – in Paraná and Santa Catarina. We recorded 40 taxa of flower visitors. The secondary forest sites showed highest, the restinga habitats lowest species richness and visitation frequency. Main visitor groups were birds, bees and butterflies. The species spectrum differed considerably among habitats and similarity was lowest between the two secondary forests in Paraná and Santa Catarina. We recorded mainly hummingbirds (54.6% of all visits) as flower visitors in Paraná, whereas flowers in Santa Catarina were dominated by bees (44.5–59.7% of all visits). The temporal pattern of visits was similar at all sites; visits occurred mainly in the morning hours. However, there was no significant correlation between number of visits and hour of day. In contrast to the expectation that Ae. nudicaulis flowers, due to their morphology, attract mainly hummingbirds, they were visited by a much wider spectrum of animal species, mainly insects and arachnids, varying according to habitat. Our findings answer the question of what attracts animals to the inflorescences and elucidate the nature of some of the manifold interactions between Ae. nudicaulis and its associated flower visitors.

The present study aimed to record all flower visitors of Aechmea nudicaulis (Bromeliaceae) and their foraging behavior as well as their role in animal–plant and animal–animal relationships, and to assess temporal pattern of visitation on flowers. In order to estimate the influence of habitat on species richness and abundance, we compared the diversity and visitation frequency of flower visitors to Ae. nudicaulis in three different habitat types – secondary forest, low and high vegetation restinga – in Paraná and Santa Catarina. We recorded 40 taxa of flower visitors. The secondary forest sites showed highest, the restinga habitats lowest species richness and visitation frequency. Main visitor groups were birds, bees and butterflies. The species spectrum differed considerably among habitats and similarity was lowest between the two secondary forests in Paraná and Santa Catarina. We recorded mainly hummingbirds (54.6% of all visits) as flower visitors in Paraná, whereas flowers in Santa Catarina were dominated by bees (44.5–59.7% of all visits). The temporal pattern of visits was similar at all sites; visits occurred mainly in the morning hours. However, there was no significant correlation between number of visits and hour of day. In contrast to the expectation that Ae. nudicaulis flowers, due to their morphology, attract mainly hummingbirds, they were visited by a much wider spectrum of animal species, mainly insects and arachnids, varying according to habitat. Our findings answer the question of what attracts animals to the inflorescences and elucidate the nature of some of the manifold interactions between Ae. nudicaulis and its associated flower visitors.

In southern Brazil, we frequently observed inflorescences of two bromeliad species, Aechmea lindenii and A. nudicaulis, being visited by ants. We recorded the species spectrum and frequency of ants on inflorescences by examining more than 200 plants in three habitats to assess whether they were specifically associated to the bromeliad flowers. We recorded up to 36 associated ant species at A. lindenii and seven at A. nudicaulis, with non-plateauing species accumulation curves. Three species richness estimators (ICE, Jack2, and Chao2) indicated 40–46 species for A. lindenii in secondary forest. Ant species of the genera Crematogaster and/or Camponotus were always among the most frequent. To explain the association of bromeliad flowers with such a high richness of ant species we tested two hypotheses: (1) ants exploit extrafloral nectar on the flowers or (2) ants hunt for abundant hummingbird-transported flower mites that likely effect plant reproduction by feeding on nectar and pollen. After excluding all flower visitors we recorded for the first time the production of extrafloral nectar at the sepal tips of the two Aechmea species from early buds to the early fruiting period. Ants were present at 88% of all inflorescences during that period. In contrast, flower mites could only be found as soon as the first flowers had opened, that is, when the inflorescences had already been visited by ants for several days. Quantitative behavioral analyses of worker ants on A. lindenii inflorescences revealed that they spent 42% of their time inspecting the sepal tips. Preying on mites was rarely observed. We conclude that the extrafloral nectar secreted at the sepal tips constitutes the main target for a high diversity of unspecialized ants. Nevertheless, the ants might ultimately serve the bromeliads by reducing the mites' impact on plant fitness. No sul do Brazil freqüentemente observamos inflorescências de duas espécies de bromélias, Aechmea lindenii e A. nudicaulis, sendo visitadas por formigas. Registramos as espécies de formigas e as suas freqüências nas inflorescências de mais de 200 plantas, em três tipos de habitat, para testar se elas foram específicamente associadas com flores de bromelias. Registramos até 36 espécies de formigas associadas a A. lindenii e sete associadas a A. nudicaulis, com curvas de acumulação de espécies não alcançando um platô. Três estimadores de riqueza (ICE, Jack2, e Chao2) indicaram 40–46 espécies para A. lindenii em floresta secundária. Espécies dos gêneros Crematogaster e/ou Camponotus sempre estiveram entre as mais frequentes. Para testar a associação de flores de bromélias com a alta riqueza de espécies de formigas nós testamos duas hipóteses: (1) formigas usam néctar extrafloral das flores ou (2) formigas atacam os ácaros muito abundantes, transportados por beija-flores, e que possivelmente interferem na reprodução das plantas por consumirem néctar e pólen. Excluindo todos os visitantes florais, registramos pela primeira vez a produção de néctar extrafloral nas pontas das sépalas das duas espécies de Aechmea no período de botões jovens até o início da frutificação. Formigas estiveram presentes em 88% de todas as inflorescências neste período. Em contraste, ácaros em flores foram encontrados somente assim que as primeiras flores abriram, momento em que as inflorescências já tinham sido visitadas pelas formigas há vários dias. Análises quantitativas do comportamento das formigas operárias em inflorescências de A. lindenii revelaram que elas ficaram 42% do seu tempo inspecionando as pontas das sépalas. Predação por ácaros foi observada raramente. Concluímos que o néctar extrafloral secretado nas pontas das sépalas constitue o principal alvo para uma alta riqueza de formigas não-especializadas. Contudo, as formigas poderiam, em última análise, beneficiar as bromélias reduzindo o impacto dos ácaros sobre as plantas.

In southern Brazil, we frequently observed inflorescences of two bromeliad species, Aechmea lindenii and A. nudicaulis, being visited by ants. We recorded the species spectrum and frequency of ants on inflorescences by examining more than 200 plants in three habitats to assess whether they were specifically associated to the bromeliad flowers. We recorded up to 36 associated ant species at A. lindenii and seven at A. nudicaulis, with non-plateauing species accumulation curves. Three species richness estimators (ICE, Jack2, and Chao2) indicated 40–46 species for A. lindenii in secondary forest. Ant species of the genera Crematogaster and/or Camponotus were always among the most frequent. To explain the association of bromeliad flowers with such a high richness of ant species we tested two hypotheses: (1) ants exploit extrafloral nectar on the flowers or (2) ants hunt for abundant hummingbird-transported flower mites that likely effect plant reproduction by feeding on nectar and pollen. After excluding all flower visitors we recorded for the first time the production of extrafloral nectar at the sepal tips of the two Aechmea species from early buds to the early fruiting period. Ants were present at 88% of all inflorescences during that period. In contrast, flower mites could only be found as soon as the first flowers had opened, that is, when the inflorescences had already been visited by ants for several days. Quantitative behavioral analyses of worker ants on A. lindenii inflorescences revealed that they spent 42% of their time inspecting the sepal tips. Preying on mites was rarely observed. We conclude that the extrafloral nectar secreted at the sepal tips constitutes the main target for a high diversity of unspecialized ants. Nevertheless, the ants might ultimately serve the bromeliads by reducing the mites' impact on plant fitness. No sul do Brazil freqüentemente observamos inflorescências de duas espécies de bromélias, Aechmea lindenii e A. nudicaulis, sendo visitadas por formigas. Registramos as espécies de formigas e as suas freqüências nas inflorescências de mais de 200 plantas, em três tipos de habitat, para testar se elas foram específicamente associadas com flores de bromelias. Registramos até 36 espécies de formigas associadas a A. lindenii e sete associadas a A. nudicaulis, com curvas de acumulação de espécies não alcançando um platô. Três estimadores de riqueza (ICE, Jack2, e Chao2) indicaram 40–46 espécies para A. lindenii em floresta secundária. Espécies dos gêneros Crematogaster e/ou Camponotus sempre estiveram entre as mais frequentes. Para testar a associação de flores de bromélias com a alta riqueza de espécies de formigas nós testamos duas hipóteses: (1) formigas usam néctar extrafloral das flores ou (2) formigas atacam os ácaros muito abundantes, transportados por beija-flores, e que possivelmente interferem na reprodução das plantas por consumirem néctar e pólen. Excluindo todos os visitantes florais, registramos pela primeira vez a produção de néctar extrafloral nas pontas das sépalas das duas espécies de Aechmea no período de botões jovens até o início da frutificação. Formigas estiveram presentes em 88% de todas as inflorescências neste período. Em contraste, ácaros em flores foram encontrados somente assim que as primeiras flores abriram, momento em que as inflorescências já tinham sido visitadas pelas formigas há vários dias. Análises quantitativas do comportamento das formigas operárias em inflorescências de A. lindenii revelaram que elas ficaram 42% do seu tempo inspecionando as pontas das sépalas. Predação por ácaros foi observada raramente. Concluímos que o néctar extrafloral secretado nas pontas das sépalas constitue o principal alvo para uma alta riqueza de formigas não-especializadas. Contudo, as formigas poderiam, em última análise, beneficiar as bromélias reduzindo o impacto dos ácaros sobre as plantas.

As part of the remarkable biodiversity of anurans in the southern range of the Brazilian Mata Atlântica, Adenomera engelsi sp. nov. is described here as a new taxon occurring on the island of Santa Catarina and adjacent coastal mainland. This litter-inhabiting frog is restricted to the Atlantic rain forest biome, living in primary and secondary woods and semi-open areas from sea level to about 900 m a.s.l., partly in sympatry with its congener A. araucaria. Both species are also referred to the Leptodactylus marmoratus group. Adenomera engelsi sp. nov. is a medium-sized member of the genus (snout–vent length 20.9–22.7 mm in males), characterized by a brown dorsal coloration with a maculated pattern of variable dark spots and blotches and a unique advertisement call, consisting of single, unpulsed notes with duration of 95–160 ms, dominant frequency between 3500 and 4300 Hz, and note repetition rates of 10–24 notes/min. Está descrita, como parte da enorme biodiversidade de anuros na região sul da Mata Atlântica brasileira, Adenomera engelsi sp. nov. que ocorre na Ilha de Santa Catarina e no litoral adjacente. A espécie está restrita ao bioma da Mata Atlântica, onde vive no folhiço em mata primária, secundária e áreas semi-abertas, desde o nível do mar até 900 m, parcialmente em simpatria com A. araucaria. Ambas as espécies também são atribuidas ao grupo Leptodactylus marmoratus. Adenomera engelsi sp. nov., de tamanho medio dentro do gênero (SVL 20.9–22.7 mm em machos), é caraterizada pela coloração dorsal marrom, com manchas escuras de tamanho e forma variável e um canto de anúncio distinto, que consiste de notas únicas e sem pulsos de 95–160 ms com frequência dominante entre 3500–4300 Hz e taxa de repetição de 10–24 notas por minuto.

As part of the remarkable biodiversity of anurans in the southern range of the Brazilian Mata Atlântica, Adenomera engelsi sp. nov. is described here as a new taxon occurring on the island of Santa Catarina and adjacent coastal mainland. This litter-inhabiting frog is restricted to the Atlantic rain forest biome, living in primary and secondary woods and semi-open areas from sea level to about 900 m a.s.l., partly in sympatry with its congener A. araucaria. Both species are also referred to the Leptodactylus marmoratus group. Adenomera engelsi sp. nov. is a medium-sized member of the genus (snout–vent length 20.9–22.7 mm in males), characterized by a brown dorsal coloration with a maculated pattern of variable dark spots and blotches and a unique advertisement call, consisting of single, unpulsed notes with duration of 95–160 ms, dominant frequency between 3500 and 4300 Hz, and note repetition rates of 10–24 notes/min. Está descrita, como parte da enorme biodiversidade de anuros na região sul da Mata Atlântica brasileira, Adenomera engelsi sp. nov. que ocorre na Ilha de Santa Catarina e no litoral adjacente. A espécie está restrita ao bioma da Mata Atlântica, onde vive no folhiço em mata primária, secundária e áreas semi-abertas, desde o nível do mar até 900 m, parcialmente em simpatria com A. araucaria. Ambas as espécies também são atribuidas ao grupo Leptodactylus marmoratus. Adenomera engelsi sp. nov., de tamanho medio dentro do gênero (SVL 20.9–22.7 mm em machos), é caraterizada pela coloração dorsal marrom, com manchas escuras de tamanho e forma variável e um canto de anúncio distinto, que consiste de notas únicas e sem pulsos de 95–160 ms com frequência dominante entre 3500–4300 Hz e taxa de repetição de 10–24 notas por minuto.