Density-dependent-dispersal
Guides
Eucallipterus tiliae
Linden aphid, Lime-tree aphid, Lime Leaf Aphid
Eucallipterus tiliae is a specialist aphid species feeding exclusively on Tilia (lime/linden) trees. Adults are readily identified by a black stripe along the body and cloudy-black wing edges. The species exhibits pronounced seasonal polyphenism in nymphal pigmentation, with first-generation nymphs always unpigmented and later generations developing black dorsal bands in response to crowding and leaf maturity. Flight behavior is density-dependent, with both direct crowding and plant-mediated cues stimulating dispersal. Native to Eurasia, it has established worldwide wherever host Tilia species occur.
Trirhabda
skeletonizing leaf beetles, goldenrod beetles
Trirhabda is a genus of skeletonizing leaf beetles in the family Chrysomelidae, comprising over 30 described species distributed in North America and Mexico. These beetles are specialist herbivores primarily associated with plants in the Asteraceae family, particularly goldenrods (Solidago), asters, and related composites. The genus has been extensively studied in ecological research due to its host-specific feeding habits, density-dependent dispersal behaviors, and potential keystone species effects on plant community dynamics. Several species are notable for sequestering defensive compounds and exhibiting complex movement behaviors in response to landscape structure and host plant quality.