Neotropical Entomology 35(5): 579-587 (2006)

No abstract

From September, 92 to August, 93 bee sampling was done in a secondary forest near the Pepital River, in Alcântara, MA, in order to study the local Euglossini fauna. Five aromatic compounds were used: eucaliptol, eugenol, methyl salicylate, vanillin, and benzoate. Four hundred sixty-seven male Euglossini bees were captured, distributed in 4 genus and 19 species. Euglossa was the most abundant and with high diversity (302 specimens and 14 species), followed by Eulaema (121; 3), Eufriesea (41; 1), and Exaerete (3; 1). The species which more frequently visited the bait were Euglossa piliventris (141 specimens; 30.19%), Euglossa cingulata (113; 24.21%), Euglossa ignita (45; 9.64%), Eufrieseapulchra (41; 8.78%), and Euglossa gaianii (33; 7.07%) corresponding to 79.88% of the sampling universe. The bees were active throughout the year, however during the rainy season more activity and diversity were observed. The most attractive essence was eucaliptol (44.32% specimens and 84.21% species). In spite of this study having been done in a forest fragment, a secondary vegetation area smaller than other areas studied in Maranhão, it showed a significant diversity rate. This result reinforces the importance of fragments in the conservation of local bee communities.

Machos de Euglossina foram coletados por meio de iscas-odores de benzoato de benzila, eucaliptol, eugenol, salicilato de metila, vanilina, durante um ano em área de mata ciliar, no município de Urbano Santos, Maranhão. As coletas foram realizadas mensalmente, entre 8 h e 16 h, totalizando 96 horas de amostragem. Foram amostrados 283 indivíduos, 4 gêneros e 16 espécies. Euglossa Latreille, 1802 foi o gênero mais abundante, seguido por Eufriesea Cockerell, 1909, Eulaema Lepeletier, 1841 e Exaerete Hoffmannsegg, 1817. As espécies mais freqüentes foram Euglossa modestior (Dressler, 1982), Euglossa cordata (Linnaeus, 1758), Eulaema cingulata (Fabricius, 1804), Exaerete smaragdina (Guérin-Menéville, 1845), Eulaema nigrita Lepeletier, 1841 e Euglossa gaianii Dressler, 1982. Eucaliptol foi a essência mais atrativa. As maiores freqüências de visitas ocorreram no período da manhã e a maior diversidade de espécies ocorreu no período chuvoso.

RESUMO -(Cargas polínicas de abelhas polinizadoras de Byrsonima chrysophylla Kunth. (Malpighiaceae): fidelidade e fontes alternativas de recursos florais). Byrsonima chrysophylla, conhecida popularmente como murici pitanga, é uma espécie arbustiva que ocorre em restinga. Dentre seus visitantes, além de abelhas da tribo Centridini, também se encontram com freqüência abelhas Xylocopini. Para verificação das espécies vegetais utilizadas pelas abelhas visitantes mais freqüentes, cargas polínicas de suas pernas posteriores (n = 5), bem como de ninhos naturais de Centris caxiensis (n = 7) foram analisados através de acetólise. Durante toda a floração, Byrsonima chrysophylla foi a principal fonte de pólen utilizada por suas abelhas visitantes. Comolia lythrarioides e Myrcia obtusa foram fontes secundárias de pólen, Mouriri guianensis foi fonte secundária de óleo e pólen, enquanto Anacardium microcarpum, Cuphea tenella, Matayba discolor e Phthirusa pyrifolia mostraram-se importantes fontes de néctar durante esse período, sendo o pólen detectado nas amostras, provavelmente aderido ao corpo das abelhas durante a coleta de néctar. Os resultados demonstram que as abelhas visitantes não misturaram os recursos polínicos durante o vôo para a coleta de pólen, apresentando fidelidade às flores de Byrsonima chrysophylla. Palavras-chave: Byrsonima, pólen, Centris, Xylocopa, fidelidade polínica, restingaABSTRACT -(Pollen loads of pollinator bees of Byrsonima chrysophylla Kunth. (Malpighiaceae): fidelity and alternative sources of flower resources). Byrsonima chrysophylla, known as "murici pitanga", is a shrubby species occurring in 'restinga'. Among its visitors, bees of the Centridini tribe as well as Xylocopini bees are frequently found. To detect which plant species have been used by the most frequent visitors, pollen loads from the back legs (n = 5) and also from natural nests of Centris caxiensis (n = 7) were treated by acetolysis. During flowering of Byrsonima chrysophylla, this plant species was the main pollen source used by bees. Comolia lythrarioides and Myrcia sylvatica were secondary pollen sources, Mouriri guianensis was a secondary oil and pollen source, while Anacardium microcarpum, Cuphea tenella, Matayba discolor and Phthirusa pyrifolia were important nectar sources at this time. The pollen detected in the samples probably adhered to the bee's body during nectar collection. The results show that the bee visitors do not mix pollen sources during the pollen-collecting flight, thus representing fidelity to Byrsonima chrysophylla flowers.

Abstract:The knowledge of the phenology patterns and of the floral biology, the determination of the role of the vectors of pollen flow, besides the understanding of the reproductive system, are fundamental points for the understanding of the reproductive biology of the species. The pollination ecology, reproductive system, flowering phenology and floral visitors of Byrsonima umbellata Mart. and B. rotunda Griseb. were studied in a Cerrado area, at Urbano Santos municipality, Maranhão State. B. umbellata presented extended flowering period (eight months) and B. rotunda showed brief flowering period (one month). The species had hermaphroditic flowers with diurnal anthesis. B. umbellata is facultatively self-incompatible, showing higher fruit production through cross-pollinators (46.6%), and B. rotunda is mainly self-compatible, with fruit production in all treatments, even through agamospermy (60%), although higher production was achieved in geitonogamy (90%). We observed 42 and 16 species of bees in B. umbellata and B. rotunda flowers, respectively. Centris aenea and C. (Trachina) sp.n. were considered the main pollinators of B. umbellata flowers and C. aenea of B. rotunda. Both Byrsonima species present important ecological function, representing important resources to several species of bees during flowering season deficit in the studied environment.

ResumoO espectro polínico do mel de Melipona fasciculata Smith foi analisado com o objetivo de identificar os recursos nectaríferos utilizados por essa espécie. A identificação das plantas visitadas foi realizada com base na análise dos tipos polínicos encontrados em 12 amostras de mel coletadas, mensalmente, em uma colônia localizada no município de Palmeirândia, na área da Baixada Ocidental Maranhense (02º40'47,6S, 44º52'39,8"W), Brasil. As análises quantitativas e qualitativas foram realizadas com o objetivo de determinar as porcentagens e classes de frequência dos tipos polínicos presentes nas amostras de mel. Foram encontrados 45 tipos polínicos, sendo Pontederia parviflora Alexander (Pontederiaceae), espécie mais frequente em todo o período de amostragem (38,6%), pólen dominante em Outubro (86%), Junho (85%), Julho (76%), Agosto (49%) e Setembro (51%) e pólen acessório em Dezembro, Janeiro e Março. Mimosa caesalpiniifolia Benth (Mimosaceae) foi a segunda espécie mais frequente (22,8%) sendo pólen dominante em Novembro (46%), Abril (74%) e Maio (72%). Myrcia eximia DC (Myrtaceae) foi considerada pólen isolado importante. As famílias mais representativas no espectro polínico das amostras de mel foram Pontederiaceae e Mimosaceae. 50% dos méis foram biflorais, havendo também méis monoflorais (41,7%) e heteroflorais (8,3%). PalavRas-Chave: Abelhas-sem-ferrão, Baixada Maranhense, Brasil, Meliponina, Melissopalinologia.Pollen spectrum of honey of "tiúba" (Melipona fasciculata Smith, 1854, Hymenoptera, Apidae) abstRaCt The pollen spectrum of honey of the Melipona fasciculata was analyzed aiming to elucidate the nectariferous resources used by this species. The identification of the visited plants was based upon the analysis of the pollen spectrum of 12 honey samples collected in one meliponarium located in Palmeirândia county, lowland area of Maranhão State, Brazil (02º40'47,6S, 44º52'39,8"W). The quantitative and qualitative analysis of honey samples was conducted in order to determine the pollen type percentages and frequency classes. Forty-five pollen types were found, being Pontederia parviflora Alexander (Pontederiaceae) the most frequent species during period of sampling (38.6%) and considered dominant pollen in October (86%), June (85%), July (76%), August (49%) and September (51%) and accessory pollen in December, January and March. Mimosa caesalpiniifolia Benth (Mimosaceae) was the second most frequent species (22.8%) and was a dominant pollen in November (46%), April (74%) and May (72%). Myrcia eximia DC. (Myrtaceae) was considered important isolated pollen. The most representative families found in the pollen spectrum of the honey samples were Pontederiaceae and Mimosaceae. 50% of honey samples was bifloral, but there were also monofloral (41.7%) and heterofloral (8.3%) honeys.

No abstract