Nyctophila reichii, commonly known as the Mediterranean firefly, is a species of firefly. The species is very common in the southern and eastern part of the Iberian Peninsula.
Fireflies are insects of the order Coleoptera, that is, of the group of beetles, and of the family Lampyridae, whose members have the remarkable characteristic of emitting light from the end of the abdomen by means of a chemical reaction. This luminescence that we see as small points of light on summer nights has the function of sexual attraction.
Nyctophila reichii, the Mediterranean firefly, is the most common species of firefly in the Bages region. Like other fireflies, Nyctophila reichii has a very marked sexual dimorphism; males and females would be considered different species if they were not seen copulating (in image 5a).
Adult females - in images 1 and 2 - are much larger than males; they have a large, swollen abdomen, about 4 cm long, light in colour with a pinkish tinge, short elytra that do not quite cover the abdomen, vestigial wings that are not used for flight and the pronotum forming a pinkish growth on the head. At night, females emit a cold, greenish light through the luminescent organs located on the ventral side of the last three abdominal segments, in order to attract a male. Females often adopt a contorted posture with the tip of the abdomen pointing upwards so that the luminescence is more visible.
The males - in images 3 and 4 - are much smaller, about 15-18 mm; they have the appearance of a typical beetle with well-developed elytra covering the abdomen and membranous wings that allow it to fly. The males of the Mediterranean firefly do not emit luminescence.
The larvae are dark and segmented, with the sides of the body red (photos 6, 7, 8 and 9). Both in the larval and adult stages, fireflies are specialized predators in the capture of snails and slugs. Image 6 shows a Nyctophila reichii larva devouring a dune snail ( Theba pisana ) .