Investigation of activity and vertical distribution of spiders in Sphagnum tussocks of peat bogs

Anotacija

plant polymorphism, metal stress, CoThe spider fauna of European peat bogs is under active investigation, but data on the activity and distribution of spiders in the hummock layer is very sparse. The optimal setting of traps for gathering most representative data in peat bogs is not known. The activity of epigeic spiders in Sphagnum moss cover and the effectivity of pitfall traps was investigated in Lithuania in 2001. Eight sets of pitfall traps (5 traps each) differing in setting design were randomly set in Sphagnum moulds of a small peat bog area. The sets variem in the depth of placement, covering and conservation liquid. A total of 1484 adult specimens of 87 species belonging to 13 families were registered. The results show that only three species (Centromerus arcanus, Lepthyphantes angulatus, Trochosa spinipalpis) were equally distributed in various depths of the moss cover. The highest number of species (63) and individuals (690) was registered in the set of traps levelled with the surface of the moss Po (Set 1). The set of traps placed 2–3 cm below the surface (Set 2, Set 8) captured two times less individuals (277) and species (40), but the number of species found in more than three specimens was quite similar in both sets. The lowest number of individuals was registered in the sets of traps placed deep in moss cover (Set 7 – N = 30, Set 6 – N = 43). Only one specines (Micrargus apertus) was registered as more abundant in deeper layers. A high activity of Trochosa spinipalpis in deep layers was registered too. No marked differences in species and individual numbers were registered between the sets with different conservation liquids (4% formalin and 10% sodžium benzoate). action, chlorophyll morphoses, regenerants, callus, Vicia faba, protochlorophyll Keywords: Araneae, peat bog, pitfall traps, Lithuania, Sphagnum