GRASSHOPPERS OF COLORADO
KEY TO STAGES OF GRASSHOPPER DEVELOPMENT
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).
Grasshoppers of Colorado Contents
A Tegmina overlying
the folded wings; tegmina and wings fully developed, often extending to
the tip of the abdomen or beyond.
ADULT (Key to Subfamilies of Acrididae)
A' Wings overlying
tegmina, or wings and tegmina poorly developed and represented by pads.
(Go to B)
B
Tegmina and wing pads pointed down (ventrally).
B' Tegmina and wing
pads pointed up (dorsally).