15 May Camel Crickets
The orthopteran family Rhaphidophoridae includes the cave weta, cave crickets, camelback crickets, camel crickets, spider crickets (sometimes shortened to “criders”, or “land shrimp” or sprickets”) and sand treaders, of the suborder Ensifera. Those occurring in New Zealand, Australia, and Tasmania are typically referred to as jumping or cave weta. Most are found in forest environments or within caves, animal burrows, cellars, under stones, in wood or in similar environments. They are characterized in part by their long antennae and legs. The well-known field crickets are from a different superfamily (Grylloidea) and only look vaguely similar, while members of the family Tettigoniidae may look superficially similar in body form.
Their distinctive limbs and antennae serve a double purpose. Typically living in a lightless environment, or active at night, they rely heavily on their sense of touch, which is limited by reach. While they have been known to take up residence in the basements of buildings, many cave crickets live out their entire lives deep inside actual caves. In those habitats, they sometimes face long spans of time with insufficient access to nutrients. Given their limited vision, cave crickets will often jump towards any perceived threat in an attempt to frighten it away. Although they look intimidating, they are completely harmless.
The group known as “sand treaders” are restricted to sand dunes, however, and are adapted to live in this environment. They are active only at night, and spend the day burrowed into the sand, to minimize water loss. In the large sand dunes of California and Utah, they serve as food for scorpions.
Cave and camel crickets are of little economic importance except as a nuisance in buildings and homes, especially basements. They are usually “accidental invaders” that wander in from adjacent areas. They may reproduce indoors, especially in situations that provide continuous dark, moist conditions, such as a basement, shower or laundry area, as well as organic debris (e.g. compost heaps) to serve as food. They are fairly common invaders of homes in Hokkaido and other cool regions in Japan, where they are called kamado-uma or colloquially benjo korogi (literally “toilet cricket”).