Theridion strepitus sp. nov. is described from lava tube caves from Isla Santa Cruz, Galapagos, Ecuador. It is the only species known in this worldwide genus that is eyeless and it is the only Galapagos species that has stridulatory picks on the male abdomen. The stridulatory apparatus demonstrates that the species is not a descendant from the other Theridion species known in the Galapagos, but is probably a relict of a lineage now extinct there in epigean habitats.
The Canadian Entomologist
Department of Biology

Peck, S. (1987). A new eyeless, stridulating theridion spider from caves in the galápagos islands (araneae, theridiidae)1. The Canadian Entomologist, 119(10), 881–885. doi:10.4039/Ent119881-10