06 September 2009

Apterogryllus species - Gryllidae

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Apterogryllus sp. - Gryllidae

Gryllidae is the largest cricket family and the members are known as the 'true crickets' when compared to other Orthoptera families. The genus Apterogryllus is an endemic one and collectively known as Wingless Burrowing Crickets, as they make extensive burrows and spend much of their time there. Their vertical burrows are 30 cm (12") or more in depth, with an enlarged living and vegetative storage chamber often with one or more side tunnels. During the heat of summer the entrance is sealed off, leaving the cricket safely entombed to emerge after seasonal rainfall.

The Australian Faunal Directory lists 20 Apterogryllus species, of which most were described or revised during the 1980's. From the distribution of these species, it is clear they are primary a tropical group, being largely found in the Northern Territory and Queensland. In Western Australia there are only 4 described species and all were collected from the far north of the State.

As these crickets are wingless, it is thought with their limited means of migration and sedentary lifestyle, various groups could easily become isolated to evolve into numerous localised species. If this speculation is valid, then the southerly distribution of the Apterogryllus species above, may mean it is undescribed

The photographs of the above male burrowing cricket were taken in late March, a time when the first rains often begin to fall and although these are not sufficient to cause flooding in our local sandy soils, it could have stirred a cricket predator requiring the cricket to flee for its life, or as I suspect, he was seeking a female wingless borrowing cricket, as is common with many burrowing male spiders at this time of year, who take advantage of pleasantly warm and humid nocturnal conditions.

My thanks to Dr David Rentz for identification.