Tetrix undulata, the common ground-hopper,[3] is a species of groundhopper in the Orthoptera: Caelifera.

[4][2] T. undulata has a body length of 6–12 mm (0.24–0.47 in); females are usually slightly larger than the males.

The colour scheme varies between different individuals and different morphs are present, from darker brownish to lighter yellow-white.

T. undulata is essentially a European species, where it is widespread: distribution ranges from Spain via France, the Benelux countries, most parts of the British Isles, Germany, Denmark, southern Scandinavia, the southwestern tip of Finland and Poland east to the Baltic States, Belarus, Ukraine, Romania and the European part of Russia.

The southern boundary of their distribution runs through the Provence, the Jura, the south of Baden-Wuerttemberg, along the northern edge of the Alps and the north of Austria via the west of the Czech Republic and Poland.