Abstract Ants are significant structural and agricultural pests, generating a need for human-safe and effective insecticides for ant control. Erythritol, a sugar alcohol used in many commercial food products, reduces survival in diverse insect taxa including fruit flies, termites, and mosquitos. Erythritol also decreases longevity in red imported fire ants; however, its effects on other ant species and its ability to be transferred to naïve colony members at toxic doses have not been explored. Here, we show that erythritol decreases survival in Tetramorium immigrans Santschi (Hymenoptera: Formicidae) in a concentration-dependent manner. Access to ad-libitum water reduced the toxic effects of erythritol, but worker mortality was still increased over controls with ad-lib water. Foraging T. immigrans workers transferred erythritol at lethal levels to nest mates that had not directly ingested erythritol. Similar patterns of mortality following erythritol ingestion were observed in Formica glacialis Wheeler (Hymenoptera: Formicidae), Camponotus subarbatus Emery (Hymenoptera: Formicidae), and Camponotus chromaiodes Bolton (Hymenoptera: Formicidae). These findings suggest that erythritol may be a highly effective insecticide for several genera of ants. Erythritol’s potential effectiveness in social insect control is augmented by its spread at lethal levels through ant colonies via social transfer (trophallaxis) between workers.
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Always under foot: Tetramorium immigrans (Hymenoptera: Formicidae), a review
The pavement ant Tetramorium immigrans is a widespread and prevalent species in temperate urban areas. Yet, despite this commonness, it was only in 2017 that T. immigrans was differentiated from other members of its complex which had largely been regarded under the umbrella species “T. caespitum”. As a result, past literature treats multiple species synonymously while current papers continue to cite T. caespitum findings as authoritative on T. immigrans. This review delineates what is known about T. immigrans while placing this information in a natural history context where possible. Given the state of our knowledge, it is likely a semi-arid open-field specialist which has multiple fortuitous “preadaptations”to human disturbance, and which has spread across Europe and North America in tight synanthropy as a result. It recruits rapidly to food, whereby making use of spotty urban resources, and is comparatively self-compatible as a species, allowing it to live at high densities where it is the dominant ant. However, it appears to have a comparatively mild impact on both human activity and biodiversity. Some future avenues of research are discussed concerning this widely distributed ant which is a convenient and interesting study system.
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- Award ID(s):
- 1656465
- PAR ID:
- 10392955
- Editor(s):
- Suarez, Andrew V.
- Date Published:
- Journal Name:
- Myrmecological news
- Volume:
- 32
- ISSN:
- 1997-3500
- Page Range / eLocation ID:
- 75-92
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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