Thanks to Graeme Smith for the following information on Tasmanian silverfish:
Heterolepisma and Ctenolepisma are easy to tell apart under the microscope. Ctenolepisma have bristles that are distinctly barbed along the length of the shaft and the last abdominal segment is trapezoidal rather than semicircular and has two small rows of bristles (or at least you can see the sockets of them) near the back corners. They also have several combs each of several bristles along the lateral margins of the thorax. The bristles of Heterolepisma are smooth except for a small fork at their ends and the last segment of the abdomen is round and only has one or two bristles in the posterior “corners” and has just a few single bristles (or maybe in groups of 2) along the lateral margins.