Genetic diversity and gene flow of the soil arthropod (Scolopendra mutilans) in urban landscapes: The roles of rivers, mountains and fragmentation

Abstract

Soil invertebrates are a major element of soil biodiversity, which play critical roles in soil ecosystems. However, the impacts of urban landscapes on the genetic diversity and gene flows of soil arthropods remain unclear. Here, we studied the genetic diversity and gene flow of Scolopendra mutilans in an urban area using mitochondrial Cytb genes and eight novel microsatellite loci. A total of 22 haplotypes and 24 variation sites were identified based on 556 bp Cytb sequences from 84 individuals of five populations in Nanjing, Jiangsu Province, China. There were 5.63–8.00 alleles in the average of eight microsatellites found in the S. mutilans arthropod populations, which showed high genetic diversity in urban landscapes. There was no correlation between the natural habitat size and genetic diversity of S. mutilans. The global Fst value based on microsatellites was 0.115, which suggested a medium genetic differentiation and population isolation. The genetic structure of S. mutilans might be affected by urbanisation, as urban patches might hinder gene flow between populations. Ecological corridors preserved in cities might serve as pathways for population migration, which increases gene flow. The gene flows of S. mutilans might not be hindered by natural barriers within cities, as there were strong relationships between populations separated by rivers. These results may contribute to the conservation of S. mutilans diversity and elucidate its adaptation to urbanisation.

Insect ecology and conservation in urban areas: An overview of knowledge and needs

“…Many works indicate a homogenisation and decrease in functional type, species diversity and/or insect abundance as urban density increases (in this SI see: Barao et al, 2024;Casanelles-Abella et al, 2024;Federico et al, 2024;Rivest & Kharouba, 2024;Sanetra et al, 2024;Svenningsen et al, 2024). This picture is, however, nuanced (e.g., Ancillotto & Rocco, 2024;Federico et al, 2024;Ombugadu et al, 2024) and although urban areas can detrimentally impact some insect taxa through the predominance of artificial environments, constrained habitats and disturbances, other taxa can adapt and thrive in the mosaic of semi-natural and novel environments, management variation and abundant resources (Curry et al, 2024;Hill et al, 2024;Nunes et al, 2024;Plummer et al, 2024;Xu et al, 2024).…”

“…Peralta et al (2011) found that walls restrict movement of a leaf miner, whereas Corcos et al (2019) found that at a local scale (< 50 m), buildings acted as barriers to movement and reduced species richness of tachinid parasitoids. Conversely, the presence of ecological green corridors connecting green spaces considered as habitat patches facilitates insect movement in urban areas and enhances the metacommunities of insects, centipedes and spiders in these patches (Balbi et al, 2020; Vergnes et al, 2012; Xu et al, 2024).…”

“…Adaptations that arise from selective pressures of urban environments have been addressed comprehensively elsewhere (Szulkin et al, 2020; Winchell et al, 2022). Here, we consider effects of the urban landscape on movement and dispersal, which are likely to translate into effects on gene flow, with consequences for genetic structure and diversity of urban insect populations (e.g., Xu et al, 2024). Overall, the fragmented nature of insect populations that rely on urban greenspaces is predicted to result in high genetic differentiation among, and reduced genetic diversity and effective population size within the local populations (Johnson & Munshi‐South, 2017; Keyghobadi, 2007).…”