Quantifying beetle-macrofungal associations in a temperate biodiversity hot spot

Area of Science:

• Ecology
• Entomology
• Mycology

Background:

• Beetles (Coleoptera) are abundant fungal consumers, but their dietary specialism remains poorly understood.
• Fungal sporocarps are a key resource, yet the factors influencing beetle associations are unclear.

Purpose of the Study:

• To characterize associations between mycophagous beetles and macrofungi.
• To quantify relationships between sporocarp traits and beetle assemblages.
• To investigate how fungal sporocarp characteristics influence beetle specialism and generalism.

Main Methods:

• Surveyed over 9000 fungal sporocarps in Appalachian montane hardwood forests.
• Collected and identified over 50,000 adult beetles across two years.
• Utilized network analyses to quantify beetle-fungus interactions and sporocarp traits (mass, age, persistence, toughness).

Main Results:

• Strict host specificity was rare; most beetles and fungi had multiple partners.
• Beetle diversity increased with sporocarp age and fresh mass in ephemeral fungi (Agaricales, Russulales).
• Softer sporocarps (Polyporales) supported greater beetle diversity than tough or woody ones.
• Interaction networks and community-level specialism/generalism varied with sporocarp age and traits.

Conclusions:

• Sporocarp traits, such as age and texture, significantly influence beetle community diversity and interaction patterns.
• Fungal sporocarp characteristics are key drivers of specialism and generalism in beetle-fungus interactions.
• Findings contribute to understanding fungal and forest ecology in a temperate biodiversity hotspot.