World’s biggest spiderweb discovered inside ‘Sulfur Cave’

Researchers found over 111,000 spiders inhabiting a colossal web spanning 1,140 square feet (106 square meters) in a pitch-black section of Sulfur Cave. The web forms a patchwork of thousands of individual funnel-shaped structures along a narrow, low-ceilinged passage near the cave entrance.​

• Scientific Significance:
  This marks the first documented colonial behavior in two common spider species, Tegenaria domestica (barn funnel weaver) and Prinerigone vagans, making it likely the largest spiderweb ever recorded. The cave was formed by sulfuric acid from oxidizing hydrogen sulfide in groundwater.​
• Research Background:
  Cavers from the Czech Speleological Society first spotted the web in 2022, with scientists collecting samples in 2024 for DNA analysis led by István Urák. The colony’s extreme conditions reveal unexpected genetic plasticity in these typically solitary species.​
• Conservation Note:
  The unique cohabitation of over 69,000 T. domestica and 42,000 P. vagans in one structure highlights the need to protect this site despite its cross-border location.

Source: LIVE Science