Eight "cerrado" (savanna) fragments in the State of São Paulo (Brazil) were surveyed from 2000 to 2002 to produce an inventory of Asteraceae species. This family is one of the most important in the herbaceous and shrubby components at cerrados. Each fragment was sampled on average once a year during the plants' peak flowering period, using a fixed number of randomly placed transects. We obtained 399 samples and recognized 89 morphospecies (of which 74 were identified to species). Forty percent of the species were encountered only once (unicates). Only ten percent of the species that occurred in more than a sample were recorded again in the same fragment or in the same year. Species richness was estimated from frequencies and abundances within transects, and then compared to the observed total richness in the area, which was most of the times higher than the estimates based on transects. Our species list was then compared to other 24 cerrado species lists in the literature. Although most of our commoner species were recorded in published lists, eight species were not found in any. We conclude that the studied cerrado fragments in São Paulo State are isolated and fragile areas composed of many rare and exclusive herbaceous and shrubby species. We suggest that the maintenance of current diversity of Asteraceae species depends on maintaining and preserving all cerrado fragments in the State. Asteraceae, "cerrado", savanna, biodiversity, São Paulo, Brazil. Key words: ResumoDe abril a maio de 2000 a 2002 oito localidades com remanescentes de cerrados sensu stricto no estado de São Paulo foram amostradas para o levantamento das espécies de asteráceas, uma das famílias mais representativas da flora herbáceo-arbustiva nestas formações. Foram feitas 23 amostragens e cada área de estudo foi amostrada em média uma vez por ano durante o pico de floração das plantas. Ao todo foram obtidas 399 amostras, nas quais foram reconhecidas 89 morfoespécies (74 foram identificadas como espécies conhecidas). Quarenta por cento das espécies foram registradas uma única vez (unicatas), indicando um grande número de espécies raras. Apenas 10% das espécies que ocorreram em mais de uma amostra foram obtidas de uma mesma área (sobreposição espacial) ou de um mesmo ano de estudo (sobreposição temporal). A riqueza de espécies em cada área foi estimada por meio de transeções e depois comparada à riqueza total observada em cada área de estudo, sendo esta na maioria das vezes mais alta que a estimada com base nas transeções. A lista de espécies obtida para os cerrados amostrados foi comparada a outras 24 listas publicadas para cerrados no Brasil. Embora a maioria das espécies mais comuns tenha coincidido, oito espécies (11% das espécies identificadas) não constam das listas publicadas. Concluímos que as áreas de cerrado sensu stricto estudadas no estado de São Paulo encontram-se isoladas, com uma grande parte da flora herbáceo-arbustiva composta por várias espécies raras e exclusivas. Diante deste quadro, sugerimos que a manutenção da b...
A survey of the endophagous insects fauna associated to Asteraceae capitula was carried out from 2000 to 2002 in eight cerrado sensu stricto sites located in the Brazilian state of Sdo Paulo. Sixty-four endophagous species of Diptera and Lepidoptera were recorded from 49 asteracean host plants. Approximately half of the species were obtained from a single locality, with a large proportion emerging from a single sample (unicates). Thirty percent of the species were singletons (i.e. only one individual was recorded). The large proportion of rare species suggests a high species turnover among localities. Lepidopteran species were recorded on more host species than dipterans, confirming their more polyphagous food habit, also observed in other Brazilian biomes and in Europe. We conclude that the studied cerrado localities, all within São Paulo State, are isolated with its invertebrate fauna composed of many rare and exclusive species. We suggest that the maintenance of Asteraceae biodiversity and their endophagous insects depend on the conservation of all cerrado remnants in the state.
-Ecological theory of habitat heterogeneity and limited niche-similarity assumes that more heterogeneous environments provide a greater amount and diversity of resources than simple environments, resulting in a greater diversity of species. This study aimed to evaluate the effect of the habitat heterogeneity on the richness of dung beetles and to examine the spatial patterns of assemblage structure in relation to patterns of habitat heterogeneity. Dung beetles were collected using pitfall traps without bait in 30 points distributed in an area of cerrado sensu lato, in the region of Tangará da Serra, MT, Brazil, including areas of cerrado sensu stricto, campo sujo, cerradão and gallery forest. A total of 1,291 dung beetles were collected, distributed in 16 genera and 29 species. Overall habitat heterogeneity exerted a negative effect on patterns of dung beetles richness. Higher levels of species richness were observed in areas of cerrado campo sujo, while the areas of gallery forest were the most species poor. Regarding assembly structure, it was found that the dung beetles were separated into two major groups, one formed by the presence of specialized species in forest areas and other composed of species that occurred predominantly in cerrado. In conclusion, it was found that habitat complexity infl uenced the distribution of dung beetles, but the level of turnover in species composition along the heterogeneity gradient was relatively weak.
-Anthropogenic changes in the landscape result in an environmental mosaic with serious consequences for biodiversity. The aim of the present study was to assess the effects of the anthropogenic changes on Asteraceae richness and abundance, and to evaluate the consequences for the richness of Tephritidae assemblages in fi ve sampling sites, with three sampled habitats in each: cerrado (Brazilian savanna), eucalyptus stands and pasture. Sampling was carried out in 15 random transects (cerrados and one pasture) and in 30 transects (eucalyptus stands and the remaining pastures). Composition, species richness and insect abundance in each habitat type was estimated by sampling the fl ower heads for each species of host plant, collected by four people for 1h. Differences in mean abundance of plant population between habitats and sites were tested by two-way ANOVA. Differences in plant species richness between habitats and sites and effects of habitat, site and host plant richness on insect richness were tested using a generalized linear model with Poisson errors. Within each sampling site, cerrados showed higher species richness of Asteraceae than pastures and eucalyptus stands. There were also signifi cant differences in plant richness among sites. Mean population abundance values were signifi cantly different among habitats, but not among sites. Increased host plant richness led to signifi cant insect species richness. There were no additional signifi cant effects of habitat on insect richness. Therefore, anthropogenic alterations in landscape determined the impoverishment of plant assemblages and therefore of insect assemblages, because of the positive relationship between host plant richness and insect richness.
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