Candy‐striped spider leaf and habitat preferences for egg deposition

Abstract

Candy‐striped spiders (Enoplognatha spp.; Araneae: Theridiidae) are among Britain's commonest theridiid spiders and are potential immigrant biocontrol agents of many pests in arable fields. Though the presence of these spiders in proximity to agriculture is dependent on the availability of suitable leaves for their egg deposition, their preference for different plant species and habitat types has not been fully investigated. Candy‐striped spiders were observed in leaf‐rolls during transect surveys of semi‐natural habitats (hedgerow, woodland and grassland) adjacent to oilseed rape fields at 10 sites across northeast England in August and September 2021. The local plant community was surveyed and compared against the leaves used by candy‐striped spiders via null models. Candy‐striped spiders preferentially deposited their eggs in hedgerow, demonstrating relative avoidance of woodland and grassland. They exhibited preference for bramble, common nettle and hogweed leaves, but also used those of dock, ash and blackthorn. Candy‐striped spiders appeared to preferentially use leaves with roughly equal length and width and avoided longer, narrower leaves irrespective of their total size. The leaves used by candy‐striped spiders are taxonomically broad, but share some morphological commonalities. Candy‐striped spiders exhibit some degree of generalism, regularly utilizing suboptimal leaves in sites lacking their preferences. The availability of preferred plants for these spiders in agriculturally proximate semi‐natural habitat may enhance their possible contribution to biocontrol.

Host Plant Specificity in Web-Building Spiders

“…Many web-building spiders often interact with and inhabit multiple plant species from different families and orders, as described, for example, by Rose et al [ 54 ] and Whitney [ 71 ]. A recent study conducted by Cuff et al [ 81 ] in England evaluated the leaf and habitat preferences for oviposition in the candy-striped spiders Enoplognatha ovata and E. latimana in the family Theridiidae. These spiders create a retreat, or nest, for oviposition by rolling a leaf with silk [ 81 ].…”

“…A recent study conducted by Cuff et al [ 81 ] in England evaluated the leaf and habitat preferences for oviposition in the candy-striped spiders Enoplognatha ovata and E. latimana in the family Theridiidae. These spiders create a retreat, or nest, for oviposition by rolling a leaf with silk [ 81 ]. Enoplognatha appeared to preferentially select the leaves of bramble ( Rubus fruticosus ), nettle ( Urtica dioica ), hogweed ( Heracleum sphondylium ), and have also been found using fireweed ( Chamaenerion angustifolium ) for their leaf-roll nests.…”

“…Enoplognatha appeared to preferentially select the leaves of bramble ( Rubus fruticosus ), nettle ( Urtica dioica ), hogweed ( Heracleum sphondylium ), and have also been found using fireweed ( Chamaenerion angustifolium ) for their leaf-roll nests. Plant preferences were not taxon-related, nor was the size and structure of leaves important; however, certain traits, such as the length–width ratio, were thought to influence leaf selection [ 81 ]. Cuff et al [ 81 ] even suggested that the spiders could possibly provide a degree of protection from herbivorous insects in a mutualistic association.…”

“…Plant preferences were not taxon-related, nor was the size and structure of leaves important; however, certain traits, such as the length–width ratio, were thought to influence leaf selection [ 81 ]. Cuff et al [ 81 ] even suggested that the spiders could possibly provide a degree of protection from herbivorous insects in a mutualistic association.…”

Sources of prey availability data alter interpretation of outputs from prey choice null networks

“…If accurately constructed, null models can elucidate the fundamental mechanisms underpinning species interactions. Null model approaches have therefore been used to explore a range of research questions including prey selectivity changes in response to perturbations (Cuff et al, 2021), seasonal variations in prey availability (Gajski et al, 2023; Verschut et al, 2019), host–parasite–parasitoid specialisation (Ramirez et al, 2022), pollinator preferences across different landscapes (Gómez‐Martínez et al, 2022), changes in foraging ecology corresponding with weather conditions (Cuff, Windsor, et al, 2023) and plant–invertebrate commensalisms (Cuff, Evans, et al, 2022). Alongside taxonomic units (e.g., species), the nodes in these networks can represent data such as consumer age class (Davies et al, 2022), functional groups (Méndez‐Castro et al, 2020) and environmental context (Cuff, Windsor, et al, 2023), increasing the value and applicability of these models.…”