Crickets in general
The crickets (Family Gryllidae) are a group of insects within the order Orthoptera (literally, “straight wing”). The Orthoptera include the grasshoppers, crickets and katydids. All Orthopterans have two pairs of wings. The front pair is hardened and leathery. When the insect is resting, this pair covers the inner second pair, which is membranous. In flighted species, the second pair is used for flight. Orthopterans have large compound eyes and long, powerful hind legs which are used for jumping. Many of them produce sounds by stridulation—rubbing one body part against another.
Crickets (the family Gryllidae) can be distinguished from grasshoppers by the fact that crickets have long antennae, while grasshoppers have short ones. Also, most crickets are nocturnal (active at night), while most grasshoppers are diurnal (active during the day). The cricket family includes three subfamilies: field crickets, ground crickets, and tree crickets. Worldwide, there are about 3,800 species, and in North America, about 100 species.
Crickets are good singers. In general, female crickets cannot produce sound, but male crickets can stridulate. They rub the bottom of their left wing against the top of the right wing to produce a chirping or trilling sound, which attracts females. Each cricket species has a unique song. Crickets can hear with “ears” situated on their front legs.
There are many myths about crickets. In Asia, they are considered to be good luck and are kept as pets. People also stage and gamble on cricket fights, especially in Asia. In Brazil, cricket song is believed to foretell rain or the coming of a large sum of money. Some people in Africa and Asia eat crickets as food; they are frequently regarded as a delicacy.
How to identify snowy tree crickets
Like most other tree crickets, snowy tree crickets have slender bodies, long, hair-like antennae, and are pale green in color. They are usually found on bushes and trees. Males have broad, clear wings; females wings are narrower and are held tightly against their bodies. Snowy tree crickets measure 15-18 mm (~3/4 inch) from the tip of the head to the tip of the abdomen.
Several other tree cricket species look very similar to the snowy tree cricket, including the narrow winged tree cricket, the black-horned tree cricket, and Davis’ tree cricket. To distinguish the snowy tree cricket from other species, look at the first two segments at the base of the cricket’s antennae. Under a magnifying glass or dissecting microscope, you can see black markings. Snowy tree crickets have one round, black spot on the first segment and one on the second segment.
Probably the easiest way to identify a tree cricket is by its very distinctive song. The snowy tree cricket is also known as the “thermometer cricket” because its chirping can be used to tell the temperature. To find the temperature in degrees Fahrenheit, count the number of chirps in 13 seconds and then add 40.
Above: A spectrogram of a snowy tree cricket's song, recorded in the lab by Alison Ravenscraft.
A spectrogram is a visual representation of sound. Time (in seconds) is on the horizontal axis, the pitch of the sound (in frequency, kHz) is on the vertical axis, and volume is represented by the darkness of the gray shading