Nesting Associations without Interdependence: A Preliminary Review on Plesiobiosis in Ants

Abstract

Plesiobiosis, the most basic form of interspecific associations in ants, denotes occasional or regular nesting of heterospecific colonies of certain species pairs in close proximity to each other without biological interdependence. Plesiobionts differ from each other both in morphology and in behaviour (e.g., in their foraging strategies), and at least one of the plesiobiotic pair is a submissive species. Recent studies on plesiobiosis have revealed thatFormica fuscaandLasius flavusare two of the most frequent plesiobionts. To date, at least 48 different plesiobiotic species pairs have been recorded from various habitat types of the Holarctic region. Two main habitat properties may play a role in the forming of plesiobiosis: the scarcity of suitable nesting sites as a forcing factor and the sufficient amount of food sources available, influencing the abundance of colonies. Thus, high colony density may contribute to the formation of such associations, resulting in (1) frequent nesting in each other's neighbourhood and (2) stronger intraspecific competition, which forces colonies into the vicinity of heterospecific nests. Plesiobiotic associations formed this way may promote persistent coexistence, leading to the formation of other types of interspecific associations (e.g., clepto- or lestobiosis).

The Plesiobiontic Association of Formica lemani Bondroit with Lasius flavus (Fabricius) (Hymenoptera, Formicidae) in Norway

“…The resources exploited by each species thus show little overlap, permitting coexistence without competition. This follows the general pattern outlined for plesiobiontic relationships by Kanizsai et al (2013). Colony sizes of the two species are listed in the literature as a few Hundred to a few thousand for F. lemani and up to 100 000 workers for L. flavus (Douwes et al, 2012).…”

“…However, in many compound nests the association appears to be fully commensal, as different species may occur together in the same nest without interacting biologically. Such associations are typically called plesiobiontic or plesiobiotic relationships (See Kanizsai et al, 2013 for a review).…”

“…size, morphology and behaviour (Kanizsai et al, 2013), andCzechowski (2004) suggested that plesiobioses primarily form in landscapes where suitable nesting habitats are scarce. In their review of plesiobiosis in Holarctic ants, Kanizsai et al (2013) noted that the ants most frequently involved in plesiobiontic relationships tend to be comparatively less aggressive ants, and that plesiobiont partners tend to show little overlap in foraging strategies.…”

“…The most frequently plesiobiont species in the Holarctic region is Formica fusca L., 1758; which forms part of more than 60% of observed plesiobiontic relationships (Kanizsai et al, 2013). Despite the two species Formica lemani Bondroit, 1917 andF.…”

“…Despite the two species Formica lemani Bondroit, 1917 andF. gagatoides Ruzsky, 1904 being overall very similar to F. fusca in behaviour and biology (Collingwood, 1979), no plesiobiontic associations of either species were listed by Kanizsai et al (2013).…”