Species richness and seasonality of spiders (Arachnida, Araneae) in an urban Atlantic Forest fragment in Northeastern Brazil

Abstract

Species richness and forest seasonality of spiders in an urban fragment of Northeastern Brazil were investigated. Mata do Buraquinho is a remnant of Atlantic Rain Forest where no spider inventories have ever been made. Samplings during dry and wet seasons were carried out in order to establish if seasonality influences species richness and complementarily of the spider fauna. Pitfall traps, nocturnal collections, and beating tray samples were used to access a multi-guild spider fauna. Spider species were estimated using first order Jackknife method. Four hundred samples were obtained, resulting in 1681 adult spiders. A total of 166 species were recorded and 211 were estimated. No significant differences for species richness were observed between both periods, and the captured species were the same according to the complementarily coefficients. The fragmentation hypothesis as factor of biota impoverishment was not tested, but future investigations on this topic are suggested in the complex of forest remnants in João Pessoa.

Richness and composition of spiders in urban green spaces in Toledo, Ohio

“…Overall, the activitydensity that we observed for spiders (22.7 spiders per trap per month) was consistent with what others have found in urban and agricultural habitats (between 0.4 and 15.9 spiders per trap per month: Shochat et al 2004;Dias et al 2006;Magura et al 2010b). We collected more spiders in lots than in forests for all, and male spiders and female activity-density was greater in lots than in gardens and greater in gardens than in forests.…”

“…Spider communities have been well examined in forest ecosystems (Miyashita et al 1998;Dias et al 2006), in agricultural settings (Riechert & Bishop 1990;Landis et al 2000;McIntyre 2000;Ö berg 2007) and on islands (e.g., Schoener & Spiller 2006), and it is evident that both natural and human disturbances strongly affect spider abundance and richness. Spiders are also affected by changes in habitat structure including changes to plant richness, architecture, and plant density (Wise 1993).…”

Does urbanization have positive or negative effects on Crab spider (Araneae: Thomisidae) diversity?

“…Studies conducted on urban spiders in countries other than Argentina report relatively fewer species of Thomisidae from green patches. For example, eight species were detected from dry and wet season samplings that combined nocturnal and manual collecting, beating trays and pitfall traps within a 500 ha urban coastal Atlantic Forest in Northeastern Brazil (Dias et al 2006). On the other hand, Burkman and Gardiner (2014) sampled vacant lots, gardens and prairies in Cleveland, Ohio, for two years, finding only 226 thomisid individuals in one genus, Xysticus.…”

Composição e diversidade da fauna de aranhas (Arachnida, Araneae) da Fazenda Nazareth, Município de José de Freitas, Piauí, Brasil

“…Entretanto, este grupo zoológico é muito utilizado em diversos trabalhos envolvendo comparações entre estimadores de riqueza em espécies (e.g., Coddington et al 1996, Sørensen et al 2002, Scharff et al 2003, Dias et al 2006, Ricetti & Bonaldo 2007, comparações e testes de métodos de coleta (e.g., Coddington et al 1991, Toti et al 2000, comparações entre habitats distintos (e.g., Lo-Man-Hung et al 2008, Hore & Uniyal 2008, sazonalidade (e.g., Dias et al 2006), estrutura de guildas (e.g., Höfer & Brescovit 2001, Dias et al 2010, impactos de fragmentação florestal (Rego et al 2007), efeitos de clareiras naturais sobre a fauna de aranhas (Peres et al 2007), fatores que influenciam a distribuição de espécies (Pinto-Leite et al 2008), entre outros. Isso se torna possível, pois as aranhas são bastante susceptíveis a mudanças microclimáticas e variações ambientais (Foelix 1996).…”

“…Neste país, a ordem encontra-se ainda mal amostrada em muitas áreas, especialmente na região nordeste, onde estas lacunas amostrais são refletidas no pequeno número de publicações de escopo ecológico, com aranhas. A região coberta pela Mata Atlântica, no Nordeste, é a melhor estudada, tendo sido registradas amostragens na Paraíba (Dias et al 2006), em Pernambuco (Peres et al 2007) e, principalmente, na Bahia (Benati et al 2005, Dias et al 2005, Oliveira-Alves et al 2005, Souza-Alves et al 2007a, b, Pinto-Leite et al 2008. Por outro lado, na Caatinga do nordeste existe apenas um inventário publicado, realizado por Carvalho & Brescovit (2005) na área da Reserva Serra das Almas, no Ceará.…”