Antennae

The antennae consist of 3-6 segments (notation I-VI). These are variable in length.
The last segment is generally the longest. It is formed from a slightly swollen basal part and a terminal part called processus terminalis.
Certain antennal segments carry sensory organs that can be rounded, oval or flat, called sensoria or rhinaria.
There are two forms of rhinaria: the primary ones located on the distal part of the last two segments and secondary ones, smaller, situated on segment III and the following ones. The secondary rhinaria are present in great numbers in the alates, especially in males.

Schéma F. Leclant

In some species, the antennae also carry hairs.