From introduction: The present study is the first attempt in southern Africa to consider an entire community of aculeate wasps and bees and their interactions with their environment as manifested by their ethology. As far as the author has been able to ascertain it is in fact the most comprehensive of its kind to have been undertaken anywhere, the only similar but more restricted account of this nature being that of Evans (1970) which is mainly concerned with fossorial species and their associates.

Made available in DSpace on 2016-02-05T18:29:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-05-18. Added 1 bitstream(s) on 2016-02-05T18:33:35Z : No. of bitstreams: 1 000856935.pdf: 5325692 bytes, checksum: 36a08bf16580ee1ba246c222676f42da (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os vespídeos sociais apresentam uma considerável abundância de espécies, participam de teias alimentares, podem atuar no controle biológico em monoculturas e no ambiente natural, atuam como possíveis polinizadores e visitantes florais frequentes. Em seis coletas realizadas em meses alternados, para cada uma das cinco áreas deste estudo no Estado de São Paulo, coletou-se 31 espécies e oito gêneros, totalizando 913 indivíduos. Desse total 81,16% são pertencentes à tribo Epiponini, 16,32% pertencem à tribo Mischocyttarini e somente 2,52% à tribo Polistini. As espécies com maior abundância foram Agelaia pallipes (298 indivíduos, frequência = 32,64%) e Agelaia vicina (210 indivíduos, frequência = 23,00%). Em relação à influência da pluviosidade na riqueza de vespas sociais, apenas na Mata Restaurada (t = 33.998 p = 0,002) e na Mata Ciliar (t = 22,583; p = 0,035) ocorreram diferenças significativas. Para a umidade relativa do ar não houve diferença significativa em nenhuma das cinco áreas. Na variável ambiental temperatura houve influência apenas na Mata Restaurada. Para pluviosidade em relação à abundância, houve uma correlação positiva na Mata Restaurada e uma negativa no Cerradão. Porém, para a temperatura, houve significância em relação à abundância na Mata Restaurada. Para o índice de diversidade de Shannon-Wiener (H') obteve-se maior valor para a Mata Restaurada (H'= 1,991). Obtivemos uma abundância de 477 (52,25%) indivíduos por busca ativa e 436 (47,75%) para armadilhas atrativas. Para riqueza, foram 31 espécies, sendo 28 (90,32%) por busca ativa e 23 (74,19%) para armadilhas atrativas, no entanto não observamos diferenças entre os métodos para a abundância e riqueza. O gênero mais abundante foi Agelaia com 30,88% nas armadilhas atrativas e 28,47% na busca ativa. Não se contatou diferença significativa entre os métodos de busca ativa e armadilhas atrativas para amostrar a riqueza de... / The Social wasps exhibit a considerable species abundance, they participated of food webs, and they can play a role in the biological control, in the monoculture and in the natural environment, they act as possible pollinators and frequent floral visitors, and the genus Polistes is considered a 'key' for the understand of evolution in the social behaviour. In 12 collects that were performed in each one of the five areas of study in the state of São Paulo, it was collected 31 species and 8 genera, which totalled 913 individuals. In this total, 81,16% belongs to the Epiponini tribe, 16,32% belongs to Mischocyttarini tribe and only 2,52% belongs to the Polistini tribe. The species more abundant were Agelaia pallipes (28 individuals, and frequency = 32,64%) and Agelaia vicina (210 individuals, frequency = 23,00%). In regarding to the influence of rainfall in the richness of the social wasps, only in the restored forest (t = 33,998 p = 0.002) and riparian forest (t = 22,583; p = 0.035) it occurred significant differences. For the relative humidity, there was no significant differences in any of the five areas. In regarding the variable environment temperature, there was only influence in the restored forest. For rainfall in regarding the abundance, there was a positive correlation in the restored forest, and a negative correlation in the ' Cerradão. However, regarding the temperature, there was a significance in relation to the abundance in the restored forest. For the Shannon-Wiener diversity index (H ') there was a greater value for restored forest (H' =1,991). It has obtained an abundance of 477 (52,25%) individuals by active search and 436 (47,75%) for attractive traps. For the richness, it was obtained 31 species, being 28 (90,32%) by active search and 23 (74,19%) by attractive traps; however, it was not observed differences between these methods for the abundance and richness. The genus more abundant was Agelaia with 30,88% in ...

Made available in DSpace on 2014-06-11T19:22:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-02Bitstream added on 2014-06-13T19:08:38Z : No. of bitstreams: 1 giratto_dt_me_rcla.pdf: 1764427 bytes, checksum: 1b64e9443f58235f6ad350ec38383d9a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Polybia paulista ou popularmente “paulistinha” é uma vespa social da família Vespidae. Possui hábitos urbanos e grande ocorrência no Sudeste do Brasil, especialmente no Estado de São Paulo, onde tem causado muitos acidentes de importância médica. Na composição de seu veneno encontra-se um potente alérgeno, a proteína Antígeno 5 (Ag5) e embora sua função biológica ainda seja desconhecida, este alérgeno é responsável por importantes reações imunológicas cruzadas com o Ag5 do veneno de outros insetos sociais e com outras proteínas de eucariotos. A importância da reatividade cruzada em pacientes alérgicos ao veneno de vespas sociais é inquestionável, pois estas interações têm impacto direto sobre o diagnóstico e a seleção da melhor conduta terapêutica. Os diagnósticos de alergia são baseados na detecção de anticorpos do tipo IgE específico ao veneno por testes cutâneos ou de sangue. No entanto, respostas falso-positivas decorrentes da reatividade cruzada e respostas falso-negativas provenientes da baixa quantidade de IgE detectada, dificultam a interpretação dos resultados. A sequência completa de cDNA (621 pb) do alérgeno Ag5 do veneno da vespa P. paulista, foi clonada e a análise dos nucleotídeos revelou uma similaridade de 99% com a vespa Polybia scutellaris. Anticorpos policlonais foram produzidos contra a fração eletroforética protéica do Ag5 (25 kDA) de P. paulista e analisados imunologicamente por Western blotting. Os resultados demonstraram que os anticorpos reconheceram especificamente o alérgeno Ag5 no veneno bruto de P. paulista bem como, desenvolveram maior reação imunológica cruzada com os alérgenos Ag5 do veneno das vespas do gênero Polybia, embora não se descarte a possibilidade de ocorrência de reação cruzada com venenos de outros insetos sociais... / Polybia paulista, commonly known as paulistinha, is a social wasp of the family Vespidae. This species occurs in urban areas and is frequent in the Southeastern Brazil, especially in the State of São Paulo, where it has been responsible for many accidents of medical significance. A potent allergen, the protein antigen 5 (Ag5), is an important compound of the wasp venom. Although its biological function remains unknown, this component is responsible for substantial cross-immunological reactions with the Ag5 of venoms of other social insects and with eukaryotic proteins. The importance of cross-reactivity in allergic patients to the wasp venoms is unquestionable, because these interactions present a direct impact on the diagnosis and on the selection of the therapeutic treatment. Allergenic diagnoses are based on the detection of IgE specific to the venom via cutaneous or blood tests. However, sometimes they are hampered by false-positive responses as a result of cross-reactivity and false-negative responses that can occur due to the low amount of IgE detected as consequence of the low sensitivity of the test. The fulllength cDNA (621 bp) from the venom allergen Ag5 wasp P. paulista was cloned and nucleotide analysis revealed 99% of similarity with the wasp Polybia scutellaris. Polyclonal antibodies were produced against the electrophoretic protein fraction of Ag5 (25 kDa) of P. paulista and immunologically analyzed by Western blotting. The results showed that the antibodies strongly recognized the allergen Ag5 in the venom of P. paulista and developed higher cross-immune reaction with the same allergen in wasp venoms of the genus Polybia, although the possibility of cross reaction with other insect venoms not tested in this study cannot be excluded. The model carried out for the Ag5 P. paulista revealed the... (Complete abstract click electronic access below)

Orientador: Edilberto Giannotti / Banca: Fabio Prezoto / Banca: Sidnei Mateus / Banca: Marcel Gustavo Hermes / Banca: Sulene Noriko Shima / Resumo: Os vespídeos sociais apresentam uma considerável abundância de espécies, participam de teias alimentares, podem atuar no controle biológico em monoculturas e no ambiente natural, atuam como possíveis polinizadores e visitantes florais frequentes. Em seis coletas realizadas em meses alternados, para cada uma das cinco áreas deste estudo no Estado de São Paulo, coletou-se 31 espécies e oito gêneros, totalizando 913 indivíduos. Desse total 81,16% são pertencentes à tribo Epiponini, 16,32% pertencem à tribo Mischocyttarini e somente 2,52% à tribo Polistini. As espécies com maior abundância foram Agelaia pallipes (298 indivíduos, frequência = 32,64%) e Agelaia vicina (210 indivíduos, frequência = 23,00%). Em relação à influência da pluviosidade na riqueza de vespas sociais, apenas na Mata Restaurada (t = 33.998 p = 0,002) e na Mata Ciliar (t = 22,583; p = 0,035) ocorreram diferenças significativas. Para a umidade relativa do ar não houve diferença significativa em nenhuma das cinco áreas. Na variável ambiental temperatura houve influência apenas na Mata Restaurada. Para pluviosidade em relação à abundância, houve uma correlação positiva na Mata Restaurada e uma negativa no Cerradão. Porém, para a temperatura, houve significância em relação à abundância na Mata Restaurada. Para o índice de diversidade de Shannon-Wiener (H') obteve-se maior valor para a Mata Restaurada (H'= 1,991). Obtivemos uma abundância de 477 (52,25%) indivíduos por busca ativa e 436 (47,75%) para armadilhas atrativas. Para riqueza, foram 31 espécies, sendo 28 (90,32%) por busca ativa e 23 (74,19%) para armadilhas atrativas, no entanto não observamos diferenças entre os métodos para a abundância e riqueza. O gênero mais abundante foi Agelaia com 30,88% nas armadilhas atrativas e 28,47% na busca ativa. Não se contatou diferença significativa entre os métodos de busca ativa e armadilhas atrativas para amostrar a riqueza de... / Abstract: The Social wasps exhibit a considerable species abundance, they participated of food webs, and they can play a role in the biological control, in the monoculture and in the natural environment, they act as possible pollinators and frequent floral visitors, and the genus Polistes is considered a 'key' for the understand of evolution in the social behaviour. In 12 collects that were performed in each one of the five areas of study in the state of São Paulo, it was collected 31 species and 8 genera, which totalled 913 individuals. In this total, 81,16% belongs to the Epiponini tribe, 16,32% belongs to Mischocyttarini tribe and only 2,52% belongs to the Polistini tribe. The species more abundant were Agelaia pallipes (28 individuals, and frequency = 32,64%) and Agelaia vicina (210 individuals, frequency = 23,00%). In regarding to the influence of rainfall in the richness of the social wasps, only in the restored forest (t = 33,998 p = 0.002) and riparian forest (t = 22,583; p = 0.035) it occurred significant differences. For the relative humidity, there was no significant differences in any of the five areas. In regarding the variable environment temperature, there was only influence in the restored forest. For rainfall in regarding the abundance, there was a positive correlation in the restored forest, and a negative correlation in the ' "Cerradão". However, regarding the temperature, there was a significance in relation to the abundance in the restored forest. For the Shannon-Wiener diversity index (H ') there was a greater value for restored forest (H' =1,991). It has obtained an abundance of 477 (52,25%) individuals by active search and 436 (47,75%) for attractive traps. For the richness, it was obtained 31 species, being 28 (90,32%) by active search and 23 (74,19%) by attractive traps; however, it was not observed differences between these methods for the abundance and richness. The genus more abundant was Agelaia with 30,88% in ... / Doutor

Orientador: Edilberto Gianotti / Banca: Fabio Prezoto / Banca: Gilberto Marcos de Mendonça Santos / Banca: Sulene Noriko Shima / Banca: Nivar Gobbi / Resumo: O presente trabalho foi realizado buscando o conhecimento de aspectos da biologia e ecologia de Angiopolybia pallens, uma importante espécie das matas úmidas brasileiras. Considerada uma espécie de alta freqüência em ambientes de Mata Atlântica do estado da Bahia, os dados coletados nos municípios de Vera Cruz-BA (12º 58’ S; 38º 36’ W Gr) e Ilhéus-BA (14º 47’ S and 39º 03’ W Gr) nos revelaram que: 1) essa vespa apresenta preferência por nidificar em folhas largas de arbustos e árvores de baixo porte (ninhos entre 0,30 e 3m do solo) localizadas em ambientes de meia sombra (clareiras e cultivos sombreados); 2) possui baixa autonomia de vôo, voando pequenas distâncias, com raio de ação efetivo de aproximadamente 24 metros e uma área de forrageamento de aproximadamente 1.800m2; 3) apresenta uma intensa atividade no início (6:00h às 7:00h) e fim do dia (17:30h às 18:00h) (ritmo circadiano bimodal); 4) tem baixo índice de eficiência na coleta de recursos, com uma equivalência entre os ítens coletados (néctar, presa e polpa); 5) reage negativamente à elevação da temperatura e luminosidade e positivamente ao incremento da umidade relativa do ar; 6) suas larvas possuem 3 ínstares e taxa de crescimento médio de 1,64; 7) suas colônias são poligínicas, sendo que, as vespas apresentam padrões de desenvolvimento ovariano variando de filamentoso a muito desenvolvido; 8) a casta das rainhas se diferencia significativamente da casta das operárias principalmente na fase de estabelecimento e 9) as castas das colônias em fase de estabelecimento são morfometricamente menores, quando comparadas com as de outras colônias com ciclo de desenvolvimento mais avançado / Abstract: The present work was carried out seeking to know aspects of the biology and ecology of Angiopolybia pallens, an important species of Brazilian rain forests. Regarded as a very frequent species in the environments of Atlantic Forest in the state of Bahia, the data collected in the cities of Vera Cruz, BA (12º 58’ S; 38º 36’ W Gr) and Ilhéus, BA (14º 47’ S and 39º 03’ W Gr) showed that: 1) this wasp prefers to nest on wide leaves of shrubs and short trees (nests between 0.30 and 3m from the ground) located in half-shaded environments (clearings and shaded cultures); 2) they have low flight autonomy and take flight for short distances, with an effective radius of action of about 24 meters and a foraging area of approximately 1,800m2; they exhibit intense activity at the beginning (from 6 to 7 a.m.) and the end of the day (from 5:30 to 6 p.m.) (bimodal circadian rhythm); they have a low efficiency rate in resource collecting, with equivalence among the items collected (nectar, prey and pulp); they react negatively to temperature or luminosity rising, and positively to increases in air relative humidity; 6) their larvae have three instars and an average growth rate of 1.64; 7) their colonies are polygynous, and the wasps show patterns of ovarian development ranging from filamentous to very well developed; 8) the queen caste differs significantly from the worker caste mainly in the establishment stage and 9) the castes of the colonies in the establishment stage are morphometrically smaller, if compared to the ones of other colonies with more advanced development cycles / Doutor

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / A doenÃa de Chagas, considerada uma doenÃa negligenciada, à uma infecÃÃo parasitÃria causada pelo Trypanosoma cruzi e endÃmica em diversos paÃses. No Brasil, apenas o Benzonidazol à usado para o tratamento da doenÃa. Nesse contexto, o potencial terapÃutico das toxinas vem cada vez mais conquistando espaÃo e despertando grandes interesses da comunidade cientÃfica. Os venenos de invertebrados tÃm apresentado grande interesse como fonte de substÃncias bioativas. Os mastoparanos, a classe mais amplamente descrita de peptÃdeos isolados a partir da peÃonha de vespas, ja evidenciaram diferentes atividades biolÃgicas. Assim, os peptÃdeos isolados tÃm despertado interesse cientÃfico como fonte de modelos moleculares para o possÃvel desenvolvimento de novas terapias farmacolÃgicas. Este estudo investigou o efeito do peptideo mastoparano (MP) isolado do veneno da vespa Polybia paulista sobre cepa Y de Trypanosoma cruzi e seu possÃvel mecanismo de aÃÃo. Formas epimastigotas de T. cruzi foram cultivadas, tratadas com diferentes concentraÃÃes de MP e incubadas durante 24, 48 e 72 horas. Formas tripomastigotas de T. cruzi obtidas atravÃs de infecÃÃo de cÃlulas LLCMK2 foram subcultivadas, tratadas com diferentes concentraÃÃes de MP e incubadas durante 24 horas. Para investigar a participaÃÃo das espÃcies reativas de oxigÃnio (ERO) no efeito citotÃxico do mastoparano sobre formas epimastigotas de T.cruzi, placas foram incubadas com a CI50 de 24h de MP e a anÃlise da emissÃo de fluorescÃncia foi realizada em citometria de fluxo apÃs adiÃÃo de DCF. O efeito de mastoparano sobre o potencial de membrana mitocontrial das formas epimastigotas foi realizado pelo ensaio com rodamina 123. A citotoxicidade foi avaliada sobre celulas Raw 264.7 e a viabilidade dos macrÃfagos foi determinada utilizando o ensaio com MTT. No estudo de Docking molecular, obteve-se inicialmente a estrutura tridimensional do mastoparano a partir da sequÃncia primÃria em programa especÃfico. ApÃs anÃlise dos sÃtios de ligaÃÃo entre peptÃdeo e enzima TcGAPDH, a estrutura cristalogrÃfica do complexo TcGAPDH-chalepina foi utilizada para comparaÃÃo. O mastoparano inibiu o crescimento das formas epimastigotas de T. cruzi, apresentando uma CI50 de 102 Âg/mL, 53,95 Âg/mL e 58,51 Âg/mL para 24, 48 e 72 horas de incubaÃÃo respectivamente. Na anÃlise da produÃÃo de espÃcies reativas houve um aumento significativo na intensidade relativa de fluorescÃncia, quando comparado ao grupo controle. O peptideo alterou o potencial da membrana mitocondrial do parasita. Para as formas tripomastigotas a CI50 foi 8,83 Âg/mL apÃs 24h de incubaÃÃo. A citotoxidade do mastoparano avaliada em macrÃfagos nÃo induziu morte celular significativa nas diferentes concentraÃÃes estudadas. No estudo de docking, foi evidenciado o acoplamento do mastoparano na TcGAPDH, demonstrando os diferentes sÃtios de ligaÃÃo dos resÃduos de aminoÃcidos do centro ativo da enzima e comparando a semelhanÃa na posiÃÃo ocupada pela molÃcula chalepina na TcGAPDH. Conclui-se que o mastoparano apresentou atividade tripanocida envolvendo a participaÃÃo do estresse oxidativo e alteraÃÃo do potencial de membrana sem apresentar citotÃxica em cÃlulas de macrÃfagos e parece inibir a TcGAPDH de T. cruzi. Portanto, o mastoparano se destaca como importante molÃcula bioativa contra os parasitas.

The Sycoecinae are a distinct and well-defined subfamily of old world fig wasps (Agaonidae, Chalcidoidea 1 Hymenoptera) , exclusively associated with the figs of Ficus species (Moraceae). The most likely sister group of the Sycoecinae was determined to be the Sycoryctini (Sycoryctinae) based largely on synapomorphies of the underside of the head. 67 sycoecine species and 3 subspecies were recognised and included in a phylogenetic analysis of the subfamily. This analysis clearly delimited six genera (four African and two extra-African), although the phylogenetic relationships between the genera were not strongly supported and remain flexible. Comparisons of the phylogeny of the Sycoecinae with the classifications of the Agaoninae and their host fig trees (Ficus, Moraceae) suggest a degree of cospeciation sensu lato. Numerous homoplasies were detected within the Sycoecinae, some of which were shared with another group of fig wasps that also enter the fig to oviposit, the Agaoninae. The anatomy of the figs apparently provides strong selection pressures that have resulted in both parallelisms and convergences within and between the two subfamilies. Among the 67 species and 3 subspecies that were recognised, 43 species and 2 subspecies are described as new. The males of three previously recognised species are also described for the first time. One generic and two specific synonyms are established together with five new combinations. Keys are provided to the genera and species, for both sexes.

Mating success and nutrient reserve effects on queen survival and nest initiation were examined with respect to the reproductive fitness of queens of the baldfaced hornet, Dolichovespula maculata. The sperm content of the Spermatheca was examined in queens of this hornet species and in queens of 10 other yellowjacket species collected in spring and summer of 1987, 1988 and 1989. Queens of the baldfaced hornet, D. maculata, were also analyzed for sperm content prior to nest initiation and during colony development. A regression model was employed to determine sperm utilization. Based on total cell counts and adult census, the sperm use efficiency of this species changed from approximately 90-100 sperm released per egg in the initial stages of colony development, to 2-3 sperm released per egg after 1000 eggs had been laid. Near the end of the season the predicted number of sperm released per egg was 0-1. The number of sperm in D. maculata males ranged from 2-2.5 million; a value considerably greater than the mean sperm number (20,223; ±4,669) found in mated spring queens (n=15). Nineteen (18.4%) of 103 yellowjacket queens analyzed in the spring seasons of 1987 and 1988 were uninseminated. The effects of mating success and sperm utilization on colony development are discussed. A significant regression of sperm content on colony size was also found for 8 species of yellowjacket. Queens of D. maculata were collected for studies of nutrient reserves before hibernation in the fall, during nest initiation, and after colonies had produced more than 2 worker broods. Fresh and dry weights were determined for all queens and a seasonal comparison of the energy reserves of lipids, sugar, and glycogen was performed on the thoracic and abdominal tagmata. Total nitrogen was also quantified to estimate protein changes by season. The results show that lipids accounted for 35% of the weight lost during hibernation, sugars 12%, and glycogen 6%. Total thoracic nitrogen remained constant throughout the year, whereas abdominal nitrogen was the same in the fall and spring queens but increased in the summer queens. The results from this study suggest that most queens which survive the winter and successfully initiate nests have similar energy reserve quantities. The implications of these findings to solitary foraging behavior are discussed. The eggs of D. maculata were examined in the spring and summer to quantify the energetic contributions provided by the queen. Mean egg weight was highest in the spring and decreased with progressive nest development. Both egg weight and energy reserves were variable among and within nests. The nutrient reserves for eggs in embryo nests, in order of importance, were lipid (22%), glucose (9.5%), and glycogen (5%). A 10-day egg incubation experiment demonstrated a mean loss of 83 ug dry weight; lipids could not completely account for the weight loss, either quantitatively or qualitatively. A study on egg developmental time failed to provide sufficient data; all eggs eventually died although embryonic larval movement was detected in 2 eggs after 16 days. The energetic contributions which a queen provides to the eggs are discussed with respect to foraging behavior and environmental influences. / Ph. D.

"April 2004" / Bibliography: leaves 152-171. / xv, 171 leaves : ill., maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2004

The worldwide knowledge of the ecology and natural history of the masarid wasps, those wasps which bee-like provision their nest cells with pollen and nectar, is synthesized and discussed putting into context the investigations concerning nesting and flower visiting by southern African masarids conducted by the present author. Masarids are found mostly to favour warm to hot areas with relatively low rainfall and open scrubby vegetation. At the generic level the masarids of the Nearctic, Neotropical and Australian regions are distinct from each other and from those of the Palaearctic and Afrotropical regions combined. No species are shared between regions. Southern Africa is apparently the area of greatest species diversity. In this region, at least, there is a high incidence of narrow endemism. Masarids are associated with a relatively small range of plant families. Where sufficient records are available distinct major preferences are shown between zoogeographical regions. Relatedness of plant preferences between zoogeographical regions is apparent when relatedness of plant taxa is considered. Within a region there is marked overlap in masarid generic preferences for flower families. At the specific level there is marked oligolecty and narrow polylecty. The majority of nesting studies indicate that nest construction, egg laying and provisioning are performed by a single female per nest, however, nest sharing has been alledged for two species. No parasitic masarids have been recorded. Egg laying precedes provisioning. Mass provisioning is the rule. According to species, nests are sited in the ground, in non-friable soil or friable soil, in earthen vertical banks, on stones or on plants. Seven nest types are defined. Three bonding agents, water, nectar and self-generated silk are used. Masarids are evaluated as potential pollinators of their forage plants in southern Africa. The "masarid pollination syndrome", though less broad is shown to fall within that designated melittophily. The case studies considered make it clear that, whereas the masarids visiting some flower groups are members of a guild of potential pollinators, the masarids visiting others are probably their most important pollinators. Increasing land utilization is shown to threaten the existence of narrowly endmic masarid species.