Macrothele funnel-web spiders

Spiders of the genus Macrothele are members of the Macrotheleidae family. While they are primarily predators, they are often observed in agricultural settings, particularly in greenhouses and orchards. These spiders are known for constructing dense, tunnel-like webs, which can interfere with normal plant development and routine cultivation practices.

The habitat preference of Macrothele usually involves undisturbed soil or the base of dense vegetation. In cultivated areas, they utilize the shelter provided by crop debris, mulch, or low-hanging foliage. By building their webs in these locations, they inadvertently create barriers that can disrupt root aeration and restrict the movement of air around the plant stem.

The life cycle of these spiders is characterized by longevity and high environmental adaptability. Females build deep burrows where they lay egg sacs, providing protection against environmental fluctuations and chemical treatments. This cryptic behavior makes them resilient to standard pest control protocols, requiring specific interventions if their density becomes problematic.

Damage caused by Macrothele is mainly indirect. The heavy webbing can trap moisture, leading to localized fungal growth on leaves and stems. Additionally, their presence can be a nuisance for workers, and in some species, the venom may pose a risk to human health, necessitating strict safety measures when handling infested plants in the field.

Management strategies for Macrothele focus on habitat modification and integrated pest control:

• Remove excessive plant debris and mulch near the base of plants to eliminate nesting sites.
• Improve ventilation in greenhouses to lower humidity levels, making the environment less favorable for web building.
• Conduct regular monitoring to identify and manually clear webbing from plants.
• Maintain clean field borders to discourage spider migration into production areas.