Blattodea (Cockroaches and Termites)

The order Blattodea historically included only cockroaches, but recently the close evolutionary link to termites (formerly classified under the order Isoptera) has been confirmed and lead to their inclusion in the family Termitidae. The cockroaches live under debris or stones on the ground, or in the foliage of plants.  Some species are nocturnal and others will be active during the day.  The diet varies from species to species but is based on living and dead plant material including wood, fruit pollen and nectar, and fungi (Fearn, 2017).  Fortunately Tasmania does not currently have the unpleasant tropical species that invade homes, but some European species have established in the state and these have the potential to become pests.  Most cockroaches lay eggs in cases are called oötheca that can be carried around by the female for varying durations before they are dropped, glued to a substrate or covered (Roth, 1991). Some species develop the eggs within their body (Rentz, 2014).  Eggs hatch into nymphs, which then grow through a varied series of stages called instars until they reach the fertile adult form.

Most termites live in tropical or sub-tropical regions of Australia, but Tasmania still has a small number of species.  They live in colonies with three main castes (Watson and Gay, 1991.  The Reproductives (kings and queens) which initially have wings that later drop off, mate and dig the first chamber where the queen lays eggs which hatch into workers.  Soldiers which are sterile males and females that have large heads and mouthparts, can shoot a sticky substance from their rostrums to defend the colony.  Workers which are also sterile males and females, build chambers and collect food. Unlike species on the mainland, Tasmanian termite species such as Porotermes live in dampwood, consuming the central core of  Eucalyptus trees and leaving “mudguts” behind (Elliott & deLittle, 1985). Other species are found in rotting logs and the base of dead branches.