The nymphal instars of grasshoppers are difficult to differentiate; first and second instars are especially easy to confuse. Also, extra instars or reduced numbers of instars are sometimes encountered. In some species, males apparently have one fewer instar than females. Extra instars generally occur between the third and fourth instars. The following generalized key will help distinguish the instars in most cases. Both macropterous (long-winged, capable of flight) and brachypterous (short-winged, flightless) species can be differentiated, using principally wing pad development, although brachypterous species are more difficult. The most useful keys to identification of grasshopper nymphs are provided by Handford (1946), Brusven (1972) and Scoggan and Brusven (1972).
A Tegmina overlying the folded wings; tegmina and wings fully developed, often extending to the tip of the abdomen or beyond.
A' Wings overlying tegmina, or wings and tegmina poorly developed and represented by pads.
(Go to B)