How Far Could the Alien Boatman Trichocorixa verticalis verticalis Spread? Worldwide Estimation of Its Current and Future Potential Distribution

Abstract

Invasions of alien species are considered among the least reversible human impacts, with diversified effects on aquatic ecosystems. Since prevention is the most cost-effective way to avoid biodiversity loss and ecosystem problems, one challenge in ecological research is to understand the limits of the fundamental niche of the species in order to estimate how far invasive species could spread. Trichocorixa verticalis verticalis (Tvv) is a corixid (Hemiptera) originally distributed in North America, but cited as an alien species in three continents. Its impact on native communities is under study, but it is already the dominant species in several saline wetlands and represents a rare example of an aquatic alien insect. This study aims: i) to estimate areas with suitable environmental conditions for Tvv at a global scale, thus identifying potential new zones of invasion; and ii) to test possible changes in this global potential distribution under a climate change scenario. Potential distributions were estimated by applying a multidimensional envelope procedure based on both climatic data, obtained from observed occurrences, and thermal physiological data. Our results suggest Tvv may expand well beyond its current range and find inhabitable conditions in temperate areas along a wide range of latitudes, with an emphasis on coastal areas of Europe, Northern Africa, Argentina, Uruguay, Australia, New Zealand, Myanmar, India, the western boundary between USA and Canada, and areas of the Arabian Peninsula. When considering a future climatic scenario, the suitability area of Tvv showed only limited changes compared with the current potential distribution. These results allow detection of potential contact zones among currently colonized areas and potential areas of invasion. We also identified zones with a high level of suitability that overlap with areas recognized as global hotspots of biodiversity. Finally, we present hypotheses about possible means of spread, focusing on different geographical scales.

Parasitism by water mites in native and exotic Corixidae: Are mites limiting the invasion of the water boatman Trichocorixa verticalis (Fieber, 1851)?

“…We can expect the opposite to the dilution effect hypothesis, which predicts that the introduction of a less competent host species may reduce infection prevalence in the native host (Telfer et al 2005). Moreover, given the likely high dispersal abilities of T. v. verticalis (Guareschi et al 2013), this species may enhance dispersal of mites and their introduction into new environments, as has been suggested for epibiotic mites infecting the invasive crab Eriocheir sinensis MilneEdwards, 1853(Normant et al 2013.…”

“…v. verticalis is a highly successful invader in coastal wetlands of higher salinities in the southern Iberian Peninsula (Rodríguez-Pérez et al 2009;Van De Meutter et al 2010b;Guareschi et al 2013). Although information remains limited, its ability to outcompete native corixids at high salinities seems to be related to its high fecundity and a capacity to complete several generations a year.…”

“…Studies of mite parasitism in corixid communities in parts of Iberia where T. v. verticalis has not yet arrived would shed light on this question. The means by which T. v. verticalis arrived on the peninsula are unknown, as is the date of arrival (Rodríguez-Pérez et al 2009;Guareschi et al 2013).…”

“…Recently it has invaded aquatic ecosystems in Africa, Oceania and Europe, where it is the only known exotic corixid (Rabitsch 2008(Rabitsch , 2010Guareschi et al 2013). It is predicted to spread extensively across Europe during the course of this century (Guareschi et al 2013).…”

On the Iberian endemism Eurylophella iberica Keffermuller and Da Terra 1978 (Ephemeroptera, Ephemerellidae): current and future potential distributions, and assessment of the effectiveness of the Natura 2000 network on its protection

“…This procedure has been widely used in spatial animal ecology (e.g. Etherington et al 2009) and is considered an useful tool to estimate the environmental suitability area for a given species (Calenge et al 2008;Sánchez-Fernández et al 2013;Guareschi et al 2013). Thus the final representation of the potential distribution for E. iberica was a map with continuous favourability values within its potential distribution, which ranged from 0 (low suitability) to 100 (high suitability).…”