Arachnologische Mitteilungen 57

Diaspores as food for spiders 33 dubius from West Africa, and from five species of European temperate regions: Chelidonium majus L. (1753), Corydalis so- lida (L. 1753) Clairv. 1811 (Papaveraceae), Galanthus niva- lis L. (1753) (Amaryllidaceae), Asarum europaeum L. (1753) (Aristolochiaceae) and Hepatica nobilis Schreb. 1771 (Ranun- culaceae). The arachnofauna of heated greenhouses in the BG PJŠU comprises 62 spider taxa in 21 families (Šestáková et al. 2017). Parasteatoda tepidariorum (C. L. Koch, 1841) (Theridiidae) and Uloborus plumipes Lucas, 1846 (Uloboridae) are the most abundant spider species here and were confronted with the diaspores of myrmecochorous plants mentioned above. As the syntopic P. tepidariorum and Parasteatoda tabulata (Levi, 1980) are barely distinguishable in their webs, they are usually referred together here as Parasteatoda sp. in this paper. Some spiders, especially cobweb spiders (Theridiidae), reside in the same place for a long time. Seventeen such si- tes with spider individuals (coded as P01–P17) were selected along inner sides of greenhouses. Below each selected spider, 20 seeds of Costus dubius were placed on the sill, trying not to touch nearby sticky threads anchored to the sill (Fig. 2a). In the following 20 days the number of seeds picked up was checked (once a day, usually around midday). Only nine Pa- rasteatoda who stayed for the full 20 days at the same site (others disappeared in the meantime) were included in the final evaluation (Fig. 1, 2). Fig. 2: A Parasteatoda sp. (in red circle) with the code P05 (see text and Fig. 1 for other details) with the seeds of Costus dubius (in blue circles) in a greenhouse of BG PJŠU. a. 20 seeds put on the sill be- low spider (10.I.2018) at the begin- ning of the test; b. Three days later (13.I.2018), 13 seeds were pulled up from the sill by this spider; c. Detail of the spider with some of the pulled up seeds (11.I.2018); d. Detail of the spider feeding on one of the seeds (15.I.2018) Fig. 3: Different individuals of Pa- rasteatoda sp. with the diaspores of: a. Costus dubius ; b. Galanthus nivalis ; c. Hepatica nobilis ; d. Che- lidoniummajus