Labyrinth spider

The Labyrinth spider (lat. Agelena labyrinthica) belongs to the order Araneae and the family Agelenidae. Within the agricultural sector, this species is occasionally classified as a pest not because it feeds on crops, but because its elaborate silk structures can interfere with plant development and hinder standard horticultural maintenance practices.

This spider does not damage plant tissues directly as it is an obligate predator, feeding exclusively on insects. The primary concern for farmers is the construction of dense, funnel-shaped webs that may cover significant parts of foliage, potentially restricting sunlight and airflow, which are critical for the healthy development of young seedlings.

The biology of Agelena labyrinthica is defined by its sedentary lifestyle. The spider builds a large, sheet-like web with a funnel retreat where it hides. Throughout the growing season, it remains in its chosen location, waiting for prey. The life cycle involves egg-laying in late summer or autumn, with the offspring overwintering in protected web structures among plant debris.

Damage symptoms are primarily indirect. The presence of these large webs can cause physical deformation of delicate shoots due to the tension of the silk. Furthermore, excessive web cover can create a humid microclimate beneath the sheets, which may inadvertently encourage the growth of molds and fungal pathogens on the leaves of the host plants.

Control measures are generally minimal, as these spiders also provide a natural benefit by preying on other insect pests. Recommended management practices include:

• Clearing away crop residues and weeds that provide anchoring points for the webs.
• Regular soil cultivation and hoeing to disturb the spider's habitat.
• Manual removal of webs during routine crop inspection.
• Ensuring optimal spacing between plants to improve air circulation and reduce favorable conditions for web construction.