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.

Blinded by the Light: Artificial Light Lowers Mate Attraction Success in Female Glow-Worms (Lampyris noctiluca L.).

Nocturnal light pollution from anthropogenic origin is increasing worldwide and is recognised as a major threat for nocturnal biodiversity. We studied the impact of artificial light on the mate attraction success of female common glow-worms (Lampyris noctiluca L.) by daily monitoring their glowing status in the field, acting as a proxy for mating status throughout the mating season. We found that females in dark surroundings typically stopped glowing after one night, indicating that they had mated, while females in illuminated areas glowed for significantly more nights, in some cases up to 15 nights. Our study confirms previous findings and hypotheses that females exposed to artificial light suffer from a reduced mate attraction success with a negative impact on populations.

Larval and adult emission spectra of bioluminescence in three European firefly species.

We studied the spectral characteristics of the larvae of three sympatric Belgian species of fireflies, Lampyris noctiluca, Phosphaenus hemipterus and Lamprohiza splendidula. An in vivo spectral study was performed to compare bioluminescence spectra. The emission spectrum of a laboratory reared female L. noctiluca was recorded by a different, more exact method. The mean peak wavelength (lambdamax = 546 nm) and shapes of the unimodal emission spectra are visually similar for the larvae of all three species. The emission spectrum of the adult female L. noctiluca peaked in the same range as the larval bioluminescence between 546 and 551 nm. The bandwidth at half-maximum intensity was slightly greater for larval L. noctiluca (77 +/- 4 nm) compared with P. hemipterus (70 +/- 10 nm). The bandwidth of larval L. splendidula (77 +/- 8 nm) was not different compared with the other larvae, whereas the females' bandwidth was somewhat narrower (68 nm). The ecological significance of the color of bioluminescence and conservancy of green emission in larval fireflies and other luminescent beetle larvae is discussed.