The Dark Side of the Light Show: Predators of Fireflies in the Great Smoky Mountains

In the Great Smoky Mountains of East Tennessee, the Light Show is a popular seasonal attraction created by thousands of courting male Photinus carolinus fireflies (Coleoptera: Lampyridae) that flash in synchrony to locate females. This study was undertaken to provide a temporal snapshot of whether invertebrate predators are active within these dense and conspicuous firefly breeding aggregations. In addition, we examined whether female Photuris fireflies, which are specialist predators on other fireflies, show any feeding preferences within the diverse local firefly fauna. A field survey revealed a surprisingly diverse suite of generalist insectivores feeding on fireflies within P. carolinus breeding aggregations. In addition, laboratory studies revealed major differences in prey consumption rates when Photuris predators were given access to several lampyrid taxa. This suite of generalist and specialist predators appears to create a complex selective landscape that is predicted to be a powerful force shaping the evolution of firefly defenses

Quick spreading of populations of an exotic firefly throughout Spain and their recent arrival in the French Pyrenees

In August 2018, a firefly (Coleoptera: Lampyridae) of American origin was observed in several localities in Girona (Catalonia, Spain) and was described as Photinus immigrans by Zaragoza-Caballero and Vinolas, 2018. Here, we show that this species dispersed very quickly throughout northeastern Spain and was, in 2020, observed in the French Pyrenees. The animal’s quick progress is documented, and part of its biology is described (dispersion speed, land use, phenology, identification of all life stages). An additional population was localized in Extremadura, and its special status is discussed. We were able to determine its Argentinian–Uruguayan origin and propose, therefore, to consider Photinus immigrans as a synonym of Photinus signaticollis (Blanchard, 1846) (=Photinus immigrans Zaragoza-Caballero and Viñolas, 2018, syn. nov.). Our data clearly show that at least the Catalan and French populations are spreading very quickly and are able to settle permanently if adequate ecosystems are found. The species is highly expansive and may well be invasive; our citizen science platforms are ideally suited to monitor their progress throughout Spain and France. This is important for avoiding future ecological problems with diverse native faunas, such as glow-worms, fireflies and earthworms. If no ways are found to stop the species’ progression, the animals will quite probably invade substantial areas of France, Spain and the rest of Europe in the years to come

Across the firefly-verse: comparison of niche suitability of an exotic firefly in its native and colonized range

2023 Acuerdos transformativos CRUEPhotinus signaticollis Blanchard, 1846 (Coleoptera: Lampyridae) is a firefly native to South America and recently established in Europe. Since 2016, this firefly has colonized the northeastern part of the Iberian Peninsula and crossed the Pyrenees to reach southern France in 2019. The larvae of this firefly feed on earthworms, so a high density of this species could negatively impact this key group in soil processes and agriculture. The precise extent of colonization, the environmental niche and the potential range expansion in non-native areas are currently unknown. Using species distribution models, we have found the high suitability areas across Europe where P. signaticollis may become established if introduced. Interestingly, using only South American records and associated conditions modelling it can be strongly predicted where the species is currently found in Europe. Despite a few propagules of P. signaticollis detected in very unsuitable areas of Spain were no longer detected after their initial observation, the climatic niche overlap between South America and Europe populations appeared to be very low. In our case, this pattern is more likely to reflect a high unfilled niche rather than a niche expansion or niche shift, because many occupied areas in South America possess a climate not occurring in Europe. Among the considered variables, we furthermore found that only the temperature seasonality appeared to be the same in both native and European areas and relevant in the models, suggesting that it may represent the main limiting factor for establishing this firefly.European CouncilMinisterio de Universidades (España)Universidad Complutense de MadridDepto. de Biodiversidad, Ecología y EvoluciónFac. de Ciencias BiológicasTRUEpubAPC financiada por la UC

Plant functional group composition and large-scale species richness in European agricultural landscapes.

International audienceQuestion: Which are the plant functional groups responding most clearly to agricultural disturbances? Which are the relative roles of habitat availability, landscape configuration and agricultural land use intensity in affecting the functional composition and diversity of vascular plants in agricultural landscapes? Location: 25 agricultural landscape areas in seven European countries. Methods: We examined the plant species richness and abundance in 4 km × 4 km landscape study sites. The plant functional group classification was derived from the BIOLFLOR database. Factorial decomposition of functional groups was applied. Results: Natural habitat availability and low land use intensity supported the abundance and richness of perennials, sedges, pteridophytes and high nature quality indicator species. The abundance of clonal species, C and S strategists was also correlated with habitat area. An increasing density of field edges explained a decrease in richness of high nature quality species and an increase in richness of annual graminoids. Intensive agriculture enhanced the richness of annuals and low nature quality species. Conclusions: Habitat patch availability and habitat quality are the main drivers of functional group composition and plant species richness in European agricultural landscapes. Linear elements do not compensate for the loss of habitats, as they mostly support disturbance tolerant generalist species. In order to conserve vascular plant species diversity in agricultural landscapes, the protection and enlargement of existing patches of (semi-) natural habitats appears to be more effective than relying on the rescue effect of linear elements. This should be done in combination with appropriate agricultural management techniques to limit the effect of agrochemicals to the fields