Ecosystem engineering by leaf-rolling mites enhances arthropod diversity

Gallers as leaf rollers: ecosystem engineering in a tropical system and its effects on arthropod biodiversity

“…The leaf shelters created by the Ditylenchus sp. are subtle and ephemeral structures, but with strong effects in community organization, as previously shown to other ecosystem‐engineered structures created by arthropods (e.g., Lill & Marquis, 2003; Nakamura & Ohgushi, 2003; Crawford et al ., 2007; Wang et al ., 2012; Vieira & Romero, 2013; Baer & Marquis, 2014; Wetzel et al ., 2016; Henriques et al ., 2019; Novais et al ., 2020). Our results demonstrated the strong and positive indirect effect of gall‐induction and leaf sheltering on diversity and composition of arthropod species at different spatial scales, revealing the positive effect of shelters induced by gallers on arthropod diversity and its indirect effects on leaf herbivory.…”

“…Arthropods sheltered inside the leaf‐rolled galls may represent important and readily available groups of prey that attract predators to these engineered structures, which is supported by the large number of spiders found in these plants, which also exhibited species composition different from plants with galls removed, indicating that arthropod communities can be influenced by these structures. These results show that the effects of galls as EE can go beyond merely providing habitat for specialists and influencing the structure of communities that do not directly interact with habitat modifications (Wetzel et al ., 2016; Novais et al ., 2020). We suggest that leaf shelters can be an adequate place to ambush and capture prey, in addition to having an adaptive value, as predators resting and nesting inside them can save time and energy by occupying already existing structures (Fukui, 2001; Vieira & Romero, 2013; Slinn et al ., 2017).…”

“…These structures can be secondarily occupied by other arthropods, that sometimes co‐occur with the EE (Cornelissen et al ., 2016). Gallers are seldom suggested as EE, representing only 4.3% of EE records for invertebrates in a global meta‐analytic review (Romero et al ., 2014), but they are important allogeneic engineers because by inducing cell differentiation – by hyperplasia and/or hypertrophy – in their host plants (Price et al ., 1986; Fernandes et al ., 2014), they create a variety of structures that can provide shelter for several arthropods, such as ants who use galls as nests (e.g., Fernandes et al ., 1988; Fukui, 2001; Shorthouse et al ., 2005; Maruyama et al ., 2012; Barbosa et al ., 2019; Novais et al ., 2020).…”

“…Galls are primarily induced by insects (Gagné, 1994; Espírito‐Santo & Fernandes, 2007) but also by nematodes (Giblin‐Davis et al ., 2004; Maruyama et al ., 2012) and they alter the architecture of host plants by providing additional shelter and resources for several organisms, including beetles (Sugiura & Yamazak, 2009), caterpillars (Cooper & Riskie, 2009), hemipterans (Fernandes et al ., 1987), spiders (Wetzel et al ., 2016), springtails (Novais et al ., 2020), and thrips (Lindner et al ., 2018). These structures can increase the diversity of associated organisms, changing for example arthropod community richness and/or composition (Crawford et al ., 2007; Maruyama et al ., 2012; Vieira & Romero, 2013; Novais et al ., 2020).…”

“…Galls are primarily induced by insects (Gagné, 1994; Espírito‐Santo & Fernandes, 2007) but also by nematodes (Giblin‐Davis et al ., 2004; Maruyama et al ., 2012) and they alter the architecture of host plants by providing additional shelter and resources for several organisms, including beetles (Sugiura & Yamazak, 2009), caterpillars (Cooper & Riskie, 2009), hemipterans (Fernandes et al ., 1987), spiders (Wetzel et al ., 2016), springtails (Novais et al ., 2020), and thrips (Lindner et al ., 2018). These structures can increase the diversity of associated organisms, changing for example arthropod community richness and/or composition (Crawford et al ., 2007; Maruyama et al ., 2012; Vieira & Romero, 2013; Novais et al ., 2020). These changes might, in turn, change the functional structure of these communities when functional groups such as herbivores and predators become more or less frequent in plants, changing ecosystem processes such as herbivory and decomposition at different spatial – leaves, plants, or patches – and temporal scales (i.e., over seasons) (see Vieira & Romero, 2013; Barbosa et al ., 2019).…”