Mole Cricket

• The male sings from a burrow he digs himself in the shape of a double horn, whose geometry amplifies the sound so effectively that his call carries more than a kilometre.
• Its front legs are a case of perfect convergent evolution with those of the mole: two entirely unrelated lineages that have arrived at the same tool.
• It has disappeared from much of Europe through agricultural intensification and the draining of wet meadows, and is protected in several countries.
• Its front legs are transformed into toothed shovels, very like a mole's, and it is a classic case of evolutionary convergence: two entirely unrelated animals solving the problem of digging in the same way.
• It builds an amplifier. The male digs a burrow shaped like a double horn, with two flared openings towards the surface, and sings from the exact spot where the geometry resonates best. The design turns his stridulation into a trill that can be heard more than a kilometre away.
• It is a much-cited case of acoustic niche construction: the horn's efficiency depends on its shape and size, and the cricket tunes it by singing and modifying the tunnel until the volume is maximised.
• It swims, flies and digs: it is one of the few insects capable of all three.
• The female cares for her clutch, something uncommon among orthopterans: she watches over the eggs in an underground chamber and keeps them clean.
• Its populations have fallen sharply in western Europe, and in the United Kingdom it is practically extinct.

Skeleton type

Invertebrate - chitin exoskeleton (insect)

Habitat and environment

Damp, soft, rich soils of vegetable plots, meadows and riverbanks

Sexual maturity

The nymphs begin to mature from the following spring, but some do not do so until their third spring

Gestation / incubation

The eggs hatch between 10 and 20 days after laying according to some sources and in 2 to 4 weeks according to others; the nymphs moult six times and take one to three years to mature

Litter / clutch size

100 to 350 eggs in an underground chamber dug in spring; the female guards them and goes on watching over the nymphs for another two or three weeks

Sources consulted: https://es.wikipedia.org/wiki/Gryllotalpa_gryllotalpa; Ficha de especie de Gryllotalpa gryllotalpa; SINA; Arkive; e-nema, ficha Mole cricket; SINA, capitulo Gryllotalpinae; Orthopterists' Society (SINA), capitulo Gryllotalpinae; Arkive, ficha Mole cricket

Best time: Spring, when the males sing at dusk from their burrows