Invertebrates
Bess Beetle
Passalidae · also called patent leather beetle
Inside a single rotting log, an entire colony of bess beetles goes about its business together, adults chewing wood into a form their own larvae can digest, the whole group staying in contact through a quiet series of squeaks most people would never think to listen for.
Overview
The bess beetle, family Passalidae, is a glossy black beetle found within rotting logs in deciduous forest across eastern North America. Its genuinely social colony lifestyle, sound-based communication, and direct parental care of larvae make it one of the more behaviourally sophisticated beetles found anywhere.
A beetle that actually talks to its family
Far from the solitary existence typical of most beetles, the bess beetle lives, works, and communicates as part of a genuine family group, using sound to coordinate colony life in a way that would be unremarkable in a bird but is genuinely striking in an insect.
Status
Least Concern — widespread and common across suitable deciduous forest habitat throughout eastern North America.
Bess Beetle: common questions
How social is a bess beetle compared to other beetles?
A bess beetle lives in a colony alongside other adults and developing larvae within tunnels carved through a single rotting log, a genuinely social lifestyle that stands out among beetles generally, most of which live and develop entirely independently without any comparable family group structure.
How do bess beetles communicate with each other?
A bess beetle communicates through stridulation, rubbing specialised body parts together to produce sound, and researchers have documented a surprisingly varied range of distinct signals used between adults and larvae within the same colony, a level of acoustic communication unusual among insects generally.
Why is it called the patent leather beetle?
The bess beetle has a smooth, glossy, jet-black exoskeleton with a sheen closely resembling polished patent leather, a visual similarity striking enough to give the species its alternate common name.
Do bess beetles take care of their young?
Yes, an adult bess beetle partially processes decaying wood before making it available to larvae within the colony, a genuine form of parental care that helps the larvae access nutrients from tough plant material they could not break down as effectively on their own.