Spatial overlap and temporal synchrony between guilds of insect hosts and parasitoids

Area of Science:

• Ecology
• Entomology
• Biodiversity research

Background:

• Understanding ecosystem functioning relies on knowledge of community structure and trophic dynamics.
• Spatiotemporal variation in insect feeding guilds and its drivers remain underexplored.

Purpose of the Study:

• To investigate spatial and temporal patterns in insect feeding guilds.
• To identify the drivers of variation in insect guild composition and species richness.

Main Methods:

• Utilized nationwide Swedish insect data from Malaise traps and DNA metabarcoding.
• Integrated a comprehensive trait database to assign species into feeding guilds (phytophages, saprophages, predators) and associated parasitoid guilds.
• Analyzed species richness patterns and their relationship with latitude, habitat, temperature, and phenology.

Main Results:

• Species richness across all insect guilds decreased with increasing latitude.
• Local variation in species richness between hosts and their parasitoids showed congruence, but they responded differently to habitat.
• Phenological peaks of parasitoid species richness occurred later than their hosts, with variable time lags among guilds.
• Guild-specific responses to temperature influenced spatiotemporal patterns, yet significant variation persisted across seasons and locations.

Conclusions:

• Spatiotemporal patterns in insect guilds are influenced by temperature, habitat, and phenological timing.
• Differential responses of hosts and parasitoids to environmental factors may lead to altered trophic synchrony.
• Climate and land-use change pose potential risks to the synchrony of insect trophic layers, with uncertain ecological consequences.