The introduced oak Quercus rubra and acorn‐associated arthropods in Europe: An opportunity for both carpophagous insects and their ant predators

Abstract

We studied the interactions involving oak acorns and associated arthropods focusing on the role of the introduced Quercus rubra in Italy. We conducted our study in areas where native oaks coexist with Q. rubra. We carried out a survey on the arthropods inhabiting fallen acorns and a colonisation experiment. Furthermore, we conducted laboratory experiments documenting the interactions among the most abundant arthropod species on Q. rubra. Acorns were colonised by ant species and carpophagous insects showing different preferences concerning acorns' position within the leaf litter and oak species. Acorns of Q. rubra were colonised frequently by ants (mostly Temnothorax nylanderi) and Cydia fagiglandana. Cydia splendana preferred native acorns, while Curculio beetles were ubiquitous. Our data suggest that ants occupy exclusively acorns previously attacked by Cydia, killing or displacing their caterpillars if still developing inside the acorns. Vertebrates may prefer to feed on Q. rubra acorns over native species. Quercus rubra has a meaningful influence on native arthropods associated with oak acorns. The ecological consequences of this interaction are still not fully clear, yet our data suggest an increase in acorn‐consuming insects, partly affecting the acorns of neighbouring native oaks, but also an increase of predatory ants.

Integrating morphology with phylogenomics to describe four island endemic species of Temnothorax from Sicily and Malta (Hymenoptera, Formicidae)

“…Part of the tribe Crematogastrini Forel, 1893 (see Ward et al 2015), Temnothorax are mostly diminutive, inconspicuous, timid and cryptically colored ants, which form small colonies with only a few notable exceptions (Prebus 2017;Seifert 2018). Due to these characteristics, most species are easily overlooked during field surveys, yet many may play important ecological roles (e.g., Prebus 2017;Seifert 2018;Giannetti et al 2022). In addition, while the vast majority of the species are free-living, several are social parasites, the correct naming of which has become a debated issue among myrmecologists (Seifert et al 2016;Ward et al 2016).…”