Passalidae are commonly known as “bessbugs”, “bess beetles”, “betsy beetles” or “horned passalus beetles”. The family is mainly tropical with most of the 500-odd species being tropical. The North America species are notable for their size, ranging from 20 to 43 mm, for having a single “horn” on the head, and for a form of social behavior unusual among beetles.
Their bodies are elongate-cylindrical and mainly black. Ventral surfaces may be covered with yellow setae. The head is narrower than the thorax, with antennae consisting of 10 antennomeres with a three-segment club. The elytra are elongated with parallel sides, and heavily striated.
These are subsocial (brood caring) beetles that live in groups within rotting logs or stumps, excavating tunnel systems within rotting wood where the females then lay their eggs. They care for their young by preparing food for them and helping the larvae construct the pupal case. Both adults and larvae must consume adult feces which have been further digested by microflora for a time, an arrangement that might be described as a sort of external rumen.
They are also able to produce fourteen acoustical signals, more than many vertebrates. Adults produce the sounds by rubbing the upper surface of the abdomen against the hind wings. The larvae produce sounds by rubbing the third leg against a striated area on the coxa of the second leg.
Source: Wikipedia
(Sabah, Malaysia)
(Singapore)
Subfamily Macrolininae
(Sabah, Malaysia)
(Sabah, Malaysia)
(Sabah, Malaysia)
Subfamily Solenocyclinae
(Sabah, Malaysia)