21 May 2012

Zebra Cockroach - Robshelfordia hartmani

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Zebra Cockroach - Robshelfordia hartmani 

The endemic Robshelfordia cockroach genus currently has 12 species and belongs to the Blattellidae family. It is thought that this species Robshelfordia hartmani, is associated with termites as they have been found in rotting, termite ridden logs, although a specimen has also been found in a cave. 

Robshelfordia hartmani is currently only known from the SW coastal region of Western Australia, with the above encountered wandering around in sandy Banksia heath, 20 km (12 miles) east of Esperance. I asked Dr D Rentz who kindly identified this species, if they were common to which he responded “it is not known if it is common. Who collects cockroaches!” This I think sums up the position of most of our indigenous roaches, specifically they are very poorly known. 

Males of this species are fully winged, but the wings of females are much reduced (as the above). However this situation does not apply to all Robshelfordia spp. for with at least one species both male and female are fully winged. 

The individual above was around 1 cm (3/8”) in head/body length and is the only one of this species I have seen over a number of years looking for unusual invertebrates, so locally they are far from being common. The name Zebra Cockroach is my own invention to better aid the recall of Esperance species, especially those people like me with a poor memory for Latin and Greek.