The life cycle of the alien boatman Trichocorixa verticalis (Hemiptera, Corixidae) in saline and hypersaline wetlands of south-west Spain

Abstract

The life cycle of the alien boatman Trichocorixa verticalis (Hemiptera, Corixidae) in saline and hypersaline wetlands of southwest Spain.

Is the spread of the alien water boatman Trichocorixa verticalis verticalis (Hemiptera, Corixidae) aided by zoochory and drought resistant eggs?

“…Approximately 300 adults of T. v. verticalis were collected during each of six visits to Veta la Palma fish ponds (VLP) in Doñana Natural Park (see Céspedes, et al., 2019; Sebastián‐González & Green, 2017; Walton et al., 2015 for further information concerning this area, and its flora and fauna; Table 1). We measured temperature, conductivity, and salinity by spot sampling in situ using a conductivity meter (WTW® ProfiLine Cond 3,110).…”

“…It has been recorded as an alien species in South Africa, New Caledonia, Morocco, Spain, and Portugal. Since its first report in Europe (Sagres, Portugal, 1997) by Sala and Boix (2005), it has been expanding along coastal areas in south‐west Iberia and northern Morocco (Carbonell et al., 2012; Guareschi et al., 2013; Taybi et al., 2020), where it has become the dominant corixid in brackish and saline permanent water bodies (Céspedes et al., 2019; Rodríguez‐Pérez et al., 2009; Van de Meutter et al., 2010).…”

“…However, there is no previous study of the drought tolerance of the eggs of T. v. verticalis in the native or introduced range (note, these subspecies are described purely based on morphological characters, and a molecular study is desirable to establish if they are really different species). Recent studies have highlighted the need to evaluate whether this subspecies has eggs resistant to desiccation or gut passage, and its potential for passive dispersal (Carbonell et al., 2016; Céspedes, et al., 2019), in order to understand how it spreads within the introduced range. The alien corixid shares its habitat with flamingos and other waterbirds that move widely within the Mediterranean region and are major vectors of dispersal of other organisms, such as aquatic plants and invertebrates (Amat et al., 2005; Green & Figuerola, 2005; Lovas‐Kiss et al., 2019).…”

Water boatman survival and fecundity are related to ectoparasitism and salinity stress

“…Given the different susceptibility of different corixid species to water mite infection [20], our results suggest water mites can have an influence on interactions among corixid species, and hence the structure of aquatic insect communities. For example, mites may limit the invasion success of the American Trichocorixa verticalis , which is now widespread in our study area [20, 26, 52].…”

“…In particular, increasing salinities will favour halotolerant species such as the alien T . verticalis [26, 52]. However, given the context-dependent nature of environmental stress and the particular characteristics of host-parasite interactions, predicting these changes is difficult, and more experimental work is required (e.g.…”