The female and larvae of these species are considered the largest light producing animal in regions like central Pennsylvania.

[7][8] Phengodes lacticollis belongs to a species that are medially smoother, and lengthways longer, known as the frontalis Lec.

It is also known that the eggs that are laid on the ground within groups are encapsulated by the female glowworm beetle for a certain amount of time.

[10] These two subspecies belong to the species Phengodes laticollis: Further, in the article, "Rendering the inedible edible: Circumvention of a millipede's chemical defense by a predaceous beetle larva (Phengodidae)", by Thomas Eisner, Maria Eisner, Athula B. Attygalle, and Jerrold Meinwald, looking at the anatomy of Glowworm Beetles, specifically their feeding apparatus, there can be a lot revealed.

The article additionally points out, "The mandibles could clearly serve for both uptake and delivery of fluid," (Eisner, 1998).

[11] This illustrated how the larvae of the P. laticollis species can use their mandibles for the intake of food or to relieve what comes out of their internal system.

When looking at the research done on the biophysical and biochemical aspects of railroad-worms, and their bioluminescence done by Vadim R. Viviani and Etelvino J. H. Bechara, it was uncovered that "The different bioluminescence colors of the lanterns of Phrrxothrix species and other phengodid species are probably elicited by the presence of luciferase isoenzymes" (Viviani and Bechara, 1993).

This conclusion presents the nature of similarities between the glowworm/railroad-worm beetles and that of fireflies, since they both carry luminescent qualities.

When looking specifically at the male and female species of these glowworm beetles, they tend to be more active at night.

Moreover, there has been evidence to reveal that females use their glowing as a warning to nocturnal predators at night (Viviani and Bechara 1997).

[19] Overall, the researchers were able to understand that the larvae devours its prey without having to come into contact with the millipede's toxic secretion.

The researchers had retrieved F. penneri gland samples with methylene chloride to study the quinone content.