Inventory of terrestrial alien arthropod predators and parasites established in Europe

Abstract

There are currently 1590 terrestrial arthropod species identified as alien to Europe. Of these, 513 are predators or parasites. The largest group is the insects (409 species), followed by spiders (47 species), myriapods (34 species) and mites (23 species). The species within these alien groupings are extremely diverse, as highlighted by the large number of families represented (115 families). The majority (66.1%) of alien arthropod predator and parasite species arrived unintentionally, but at least 174 (33.9%) have been introduced intentionally, mainly for biological control purposes. Assessment of the major invasion pathways is difficult due to the lack of comprehensive information but it is likely that the majority of predatory or parasitic alien arthropods arrive through leading-edge dispersal or as contaminants and stowaways. The number of new species arriving in Europe has progressively increased since 1500, with the increase in global trade over the last century accelerating this rate of increase. Only a small number of alien predatory and parasitic arthropods in Europe have been shown to cause either an ecological or economical impact, yet knowledge is severely limited by a paucity of data.

Ecology of Arachnida alien to Europe

“…However, Kobelt and Nentwig (2008) found the eastern Palaearctic and the Indomalayan regions provided a significantly higher number of introductions than expected, whereas the Nearctic, Neotropical, and Afrotropical regions provided a significantly lower number of introduced species than expected, based on trade volume, area size, and geographical distance. The origin of 15% of spiders alien to Europe is doubtful or unknown, comparable to the global proportion of cryptogenic alien predators and parasites in Europe (Roy et al 2011b).…”

“…Unlike some other predators and parasitoids (cf. Roy et al 2011b) arachnids (again except mites, such as Phytoseiidae) are not being intentionally released as biological control agents.…”

“…Thirty-three percent of alien spiders have an Asian origin (Nentwig and Kobelt 2010) compared to 28% of all predatory and parasitoid aliens (Roy et al 2011b). About 20% come from North America (cf.…”

Alien arthropod predators and parasitoids: interactions with the environment

“…This is especially true in the case of arthropod predators and parasitoids (Roy et al 2011). Some of these entomophagous arthropods establish in new geographic regions as the result of being placed there intentionally, and being introduced specifically to agricultural or urban settings, through the practice of classical biological control.…”

Plum (Prunus spp.) aphid guild (Hemiptera: Sternorrhyncha, Aphididae) structure in Lithuania: any impact of an alien aphid species?

“…It is common knowledge that invasive species not only increase in numbers and spread geographically after their introduction into a new area, but might also start threatening the biodiversity of the invaded areas (UNEP, 2002;Mooney, 2005;DAISIE, 2009;Estoup, Guillemaud, 2010). The possible impact of the alien invasive species on the native biota concerns multiple interactions and is not easy to prove unambiguously (Sakai et al, 2001;Roy et al, 2011;Jeschke et al, 2012). Therefore, comparative analysis of native communities before and after the invasion is important both from the theoretical and practical viewpoints.…”