Evidence for displacement of a North American spider, Steatoda borealis (Hentz), by the European species S. bipunctata (Linnaeus) (Araneae: Theridiidae)

摘要: The European spider Steatoda bipunctata has apparently been introduced into North America through human transport. earliest American collections were made in Nova Scotia 1913. Until about 1933, specimens known only on the coast of Atlantic provinces, Maine, and along St. Lawrence River Lake Ontario, but they are now found widely Provinces, northernmost New England, southern Quebec Ontario. Habitats include buildings, bridges, piles lumber firewood, crevices tree trunks or among rocks. Evidence indicates that S. bipunctata, which closely resembles native borealis size, colour, microhabitat, diel activity, prey selection utilization, life history, sexual behaviour, can displace borealis. Displacement is, however, partial, as persists forest habitats, where influence is minimal. Laboratory tests reproductive potential interspecific aggression failed to demonstrate method by displaceme...