|Adult Photinus sp. specimens
Cody Hough collection
Many, see text
The Photinini are a large tribe of fireflies in the subfamily Lampyrinae. Photinus pyralis is famous in biotechnology for its luciferase gene. This is sometimes employed as a marker gene; genetically modified organisms which contain it start to glow like the firefly when brought in contact with a luciferin-containing medium. Firefly luciferases differ slightly between taxa, resulting in differently colored light and other properties, and in most cases where "firefly luciferase" is used in some application or study, it is the specific luciferase of P. pyralis
The delimitation and relationships of the many genera are often insufficiently resolved. For example, Lamprohiza and Phausis as presently delimited are apparently paraphyletic in respect to each other. The Phosphaenini, containing Phosphaenus and some other genera from the Holarctic, might indeed be a tribe distinct from the main North American lineage of Photinini, as was once proposed. Phausis may be even more distinct.
Among the Lampyrinae, the Phosphaenus group seems to occupy an even more basal position than the ancient and probably unrelated lineages assembled in the Cratomorphini (a possibly invalid group); most do not produce any light and rely on pheromone communication instead, though Lamprohiza produces a continuous glowing light. The Photinus group, though, contains flashing "lightning bugs" and some that have lost the ability to produce light signals, and is apparently much closer related to the advanced Lampyrini.
Photinini sensu stricto:
- Ellychnia Blanchard, 1845
- Photinus – rover fireflies (possibly paraphyletic)
- Pyropyga Motschulsky, 1852
Possibly separable as Phosphaenini:
The puzzling genus Lucidina might also belong here.
- Stanger-Hall et al. (2007)