Density-dependent-regulation
Guides
Aphrophorinae
Aphrophorinae is a subfamily of spittlebugs (family Aphrophoridae, order Hemiptera) characterized by their xylem-feeding habits and association with grasses and herbaceous vegetation. Members are known hosts for Strepsipteran parasites, with documented density-dependent parasitism regulating host populations in African grasslands.
Eurosta solidaginis
Goldenrod Gall Fly, Goldenrod Ball Gall Fly
Eurosta solidaginis is a tephritid fruit fly that induces spherical stem galls on goldenrod plants (Solidago spp.). The species is notable for its freeze tolerance, surviving temperatures down to -80°C through the production of unique acetylated triacylglycerols that remain liquid at low temperatures. Populations exhibit host-race formation, with genetically differentiated populations associated with different Solidago host species showing assortative mating. The galls serve as nutrient-rich overwintering chambers and have been demonstrated to accumulate environmental contaminants at higher concentrations than surrounding plant tissues, making them useful as biological pollution detectors.
Phytomyza ilicis
holly leaf miner, European Holly Leafminer
Phytomyza ilicis is a small agromyzid fly whose larvae create distinctive pale leaf mines in European holly (Ilex aquifolium). Native to Europe, it has been introduced to western North America where it became a significant pest of ornamental holly. The species is univoltine, with highly synchronized phenology: adults emerge in late spring to oviposit into the soft tissue of newly expanding leaves, and larvae feed internally until completing development the following spring. It has been extensively studied as a model system for understanding population regulation, density dependence, and multi-trophic interactions including parasitism and predation.