Tetrix undulata : Common groundhopper
Unlike the previous species, this groundhopper is a sturdy looking insect with a pronotum
that does not extend beyond the hind femora. The hindwings are much shorter than the
pronotum. T. undulata varies considerably in colour from almost black to a sandy
colouration on a greyish background. It is much more tolerant of dry conditions than the
previous species, and is often found alongside it in moist habitats. It favours mossy
ground cover in many of our woodlands; particularly on the Backwarden reserve, which is
part of the Danbury Common complex in central Essex.
Because of their small size and often dark colouration, both our groundhoppers are
difficult to detect and are often found incidentally when one is out walking.
T. undulata appears to be widespread though localised in the County and is almost
certainly under-recorded here. Like the previous species, further field work should
produce many new records, yielding a more accurate picture of its distribution.
Tetrix undulata
Omocestus viridulus: Common green grasshopper
A medium-sized grasshopper, usually green in colouration, 0. viridulus is a relatively
scarce insect in Essex. It occurs only in the western half of the County and appears to be
most common in the Epping Forest area where damp, coarse grassland suits this insect's
requirements; although it is probably under-recorded here. It has also been found in
good numbers at Hatfield Forest and is widespread but local over a fairly large area at
Mill Green, near Ingatestone in central Essex, where the damp soils support both Ling
Page 31