Tropical Trees as Islands: Diversity Accumulation of Armored Scale Insects (Hemiptera: Diaspididae) on Trees as a Function of Forest Age

Armored scale insects (Hemiptera: Diaspididae) are some of the most invasive insects in the world. These cryptic plant parasites are most often encountered in managed agricultural ecosystems, but very little is known about their distribution, abundance, and diversity in tropical rainforest canopies, where they are likely to have their highest diversity. Because these ubiquitous insects are extreme generalists with undirected dispersal, their diversity (alpha and beta) accumulation can conceivably be modeled according to tenets derived from island biogeography theory. For example, one expectation is that older established trees should boast a higher species diversity and abundance than younger ones. Other aspects of island biogeography theory have been unexplored, especially in regards to expected phylogenetic patterns of community structure. In this study we combine an intense ecological survey with a community phylogenetics approach to examine these unexplored aspects. Specimens were collected in an intensive survey from both (1) a tropical rainforest canopy using a canopy access crane in the Daintree Rainforest in Australia; and (2) an adjacent five year-old reforestation plot that had a similar diversity and constituency as the mature plot. We use a combination of systematic environmental sampling and molecular and morphological species delimitation techniques to compare and contrast the abundance, diversity, and community phylogenetics of these two habitats in order to address this question.