4. Genus Halmatettix Hancock, 1909

Halmatettix is found in Peru, Bolivia and southeastern Brazil (Fig. 37) and currently has five species, Halmatettix allardi Grant, 1955 (Figs. 12, 13); Halmatettix cristinotus Hancock, 1909 (Fig. 14); Halmatetix furcatus Grant, 1955 (Fig. 15); Halmatettix major Grant, 1955 (Fig. 16); Halmatettix sordidus Grant, 1955 (Fig. 17) (Grant, 1955a, 1962, Cigliano et al. 2021). This genus is characterized by pronotum tectate; frontal costa elevated, lateral carinae cristate; antennae with 19-22 segments; pronotal lobes with tegminal sinus absent or weakly developed, ventral sinus weakly developed; brachypronotal; tegmina fully exposed or, usually, only partly exposed (cryptic) or absent; wings cryptic or lacking; middle femora with a short, usually blunt, median dorso-apical spine (sometimes barely indicated) (Grant, 1955a, 1962) and the species are readily distinguished by the morphology of the pronotal scapular area and the degree of furcation exhibited by the lateral carinae of the frontal costa (Grant, 1955a).

There is some doubt in Halmatettix distinction with some species of Tettigidea, but a detailed study of the specimens allows distinguishing these two taxa easily. Halmatettix is a robust taxon and has tegmina lacking or cryptic, tegminal sinus absence or vestigial and no macropronotal form is known. In Tettigidea, there are specimens macropronotal and brachypronotal with the wings normally developed, but sometimes reduced; tegmina presence and tegminal sinus always present and well defined, except Tettigidea empedonepia Hubbell, 1937 (Fig. 41).