Habitat:
Omocestus defauti inhabits rocky slopes and especially scree in altitudes between 400 and 1400m.
Life cycle:
The adults appear in summer and autumn. They are quite inconspicuous and usually keep themselves on stones within the screes.
Remarks:
Omocestus defauti is endemic to Corsica and known only from few sites in the north.
Hints on determination:
The females may look similar to those of Chorthippus corsicus. Details in the wings and especially the pronotum keels are helpful. The keels are more incised in defauti, not coherent in this incised center (broad colour gap) and form a regular x when elongated imaginarily.