Natural prey ot the crab spider Rundnia grammica (Araneae: Thomisidae) on Eryngium plants

摘要

The natural prey of the crab spider Rundnia grammica (C. L. Koch, 1837) inhabiting Eryngium plants was studied in Absheron Peninsula, Azerbaijan. The percentage of specimens of R. grammica found while feeding was low (8.9%). Adult males fed significantly less frequently than adult and immature females. Investigation has shown that R. grammica is a polyphagous predator feeding on a wide range of arthropods. Representatives of four arthropod orders were found in its diet. The primary food of R grammicawas Diptera, which accounted for 65.9% of total prey. The length of prey killed by R grammica ranged between 0.82 and 15.00mm (mean 7.96mm) and constituted from 40.2 to 202.7% (mean 134.0%) of the length of their captors. The most frequently captured prey were large arthropods, exceeding the size of the spiders (86.4%). Adult males, however, captured exclusively prey smaller than themselves.