Edaphic and arboricolous oribatid mites (Acari; Oribatida) in tropical environments: changes in the distribution of higher level taxonomic groups in the communities of species

Abstract

We analysed the community of oribatid mites in 25 environments of northern Brazil and one in a rain forest in Peru, encompassing fauna sampled on natural and artificial (nylon-mesh bags) substrata, from primary and secondary forests, caatinga, savannahs, flooded forests, bark and epiphytes of trees, and polyculture. A hundred and forty six species are definitively identified from a total of 444 taxa. To determine changes in the community, we took as a basis of comparison the species dominance of Lower Oribatida vs. Oppioidea and Lower Oribatida vs. Poronota. Even considering the different periods in which the inventories were realized and the different sampling methodology compared, the partition of the species of Oribatid mite in larger groups shows tendencies indicating partition of species dominance among the environments studied, showing that they differed in their suitability as habitats for the Oribatid mite community, mainly in respect to the Lower Oribatida, Oppioidea and Poronota composition. These tendencies should be explored in more detail as more becomes known about the species composition in each environment.Keywords: humid tropics, Lower Oribatida, Oppioidea, Poronota, soil invertebrates. Oribatídeos (Acari; Oribatida) edáficos e arborícolas em ambientes tropicais: mudanças na distribuição de grupos taxonômicos superiores nas comunidades de espécies ResumoAnalisou-se comunidade de ácaros oribatídeos em 25 ambientes do Norte do Brasil e em uma floresta no Peru, compreendendo fauna de substratos naturais e artificiais (sacos de malha) coletada em florestas primárias, florestas secundárias, caatinga, savanas, florestas inundáveis, casca e epífitas de árvores e policultivo. Cento e quarenta e seis espécies são definitivamente identificadas de um total de 444 taxa. Foram comparadas as dominâncias de espécies de Oribatida Inferior vs. Oppioidea e Oribatida Inferior vs. Poronota para determinar as mudanças na comunidade. Mesmo considerando os diferentes períodos dos inventários e as diferentes metodologias de coleta comparadas, a partição de espécies de Oribatida em grandes grupos mostra tendências que podem ser indicadoras da partição da dominância entre os ambientes estudados, indicando que eles diferiram em suas qualidades como habitat para a comunidade de ácaros oribatídeos, principalmente no que diz respeito à composição dos Oribatida Inferiores, Oppioidea e Poronota. Essas tendências devem ser exploradas com mais detalhes à medida que se conheça mais sobre a composição das espécies em cada ambiente.

Species diversity of edaphic mites (Acari: Oribatida) and effects of topography, soil properties and litter gradients on their qualitative and quantitative composition in 64 km2 of forest in Amazonia

“…As one example, the ratio between Lower Oribatida versus Oppioidea was compared in 12 sites in Germany (Beck et al 1997), whose numbers varied from 0.13 to 1.69 (on average 0.60). In contrast, on the litter and soil of 17 environments in northern Brazil and one in a rain forest in Peru, the ratio varied from 1.3 to 26.7 (on average 10.3; Franklin et al 2007), which represents an average probability to find much more species belonging to Lower Oribatida.…”

“…Franklin et al (1997a) attributed the difference in their taxonomic composition at different latitudes as a possible cause, as most species in tropical forest have a low reproductive rate, like Lower Oribatida, in contrast to the species from temperate forest soils, which have a high reproductive rate, like Oppioidea. The litter in tropical forest is relatively weakly developed compared to litter in temperate or cooler woodland, and the diversity of Oppioidea is much lower compared to temperate or cooler forest (Beck et al 1997;Woas 2002;Franklin et al 2007). Representatives of Oppioidea have a high reproductive rate (Stefaniak and Seniczak 1981) which results in a high number of individuals per species (Franklin et al 1997a).…”

Synthesis of the first 10 years of long-term ecological research in Amazonian Forest ecosystem – implications for conservation and management

“…Some animal groups, especially those assumed to have limited dispersal -such as amphibians (Menin et al, 2008) and Q2 soil invertebrates (Araújo, 2007;Franklin et al, 2007;Oliveira et al, 2009;Dambros, 2010;Souza et al, 2012) -displayed distributions to some degree associated with topography and soil characteristics. There is evidence that abundance and diversity of edaphic arthropods are associated with differing levels of C, P, Na and Ca in litter and/or in soil.…”