Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes


TaxonomyBrowse
Info
ImagesLinksBooksData

Family Phengodidae - Glowworm Beetles

Glowworm Beetle- Phengodes sp. - Phengodes - male Phengodidae larva, glowing - Phengodes plumosa - female Which Glowworm Beetle? - Phengodes - male Phengodidae - Phengodes - male Cenophengus debilis LeConte - Cenophengus debilis Pterotus obscuripennis ? - Zarhipis integripennis I'm not even sure of the correct order of this one. - Phengodes Glowworm Beetle? - Distremocephalus - male
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga (Water, Rove, Scarab, Long-horned, Leaf and Snout Beetles)
Superfamily Elateroidea (Click, Firefly and Soldier Beetles)
Family Phengodidae (Glowworm Beetles)
Other Common Names
Glow-worms, Railroad Worms
Numbers
23 spp. in 6 genera of 2 tribes north of Mexico, >250 spp. in the New World; two subfamilies: Phengodinae (New World) and Rhagophthalminae (Asia)(1)
Identification
Adult males have variously shortened/narrowed soft elytra, branched antennae, and bulging eyes; adult females are larviform (often all but impossible to tell from fully-grown larvae) and, like the larvae, have bioluminescent organs(1)

J. M. Cicero provided this information on distinguishing adult females from larvae:
"Adult females are of course much larger, having supernumerated beyond the male instar count and/or grown larger on nutritional bases; we really don't know which of these factors is responsible for the larger size. Zarhipis and Phengodes larvae, at least, have strong opaque dorsal sclerites while in the female, those markings are bleached and weak. Lastly, females have a semi-circular slit on the penultimate ventrite that is associated with a copulatory gonopore. Larvae don't have either."
Range
the Americas and Asia; in our area, mostly so. US, with 1 sp. (Phengodes plumosa) reaching ON(1)(2)
Food
adult females and larvae feed on millipedes(1); adult males do not feed
Remarks
mostly nocturnal; males come to lights(3)