Of the described Australian Paederus species, P. australis can be separated on the following combination of characters: antennae blackish (entirely except first three segments with parts reddish); mandibles red; abdominal segments 2-5 reddish; and legs black (ignoring coxae).
Only six Paederus species listed for Australia have abdominal segments 2-5 exclusively reddish – P. angulicollis, P. australis, P. fuscipes, P. koebelei, P. stenopterus, and P. tweedensis. From the above combination of characters described for P. australis, the other species differ by the following: P. angulicollis has black mandibles (and the colouring on the abdomen is generally obscure); P. koebelei has black mandibles, antennae apically reddish, and femora with some reddish colouring basally; P. stenoperus has antennae apically reddish and femora with some reddish colouring basally; P. fuscipes and P. tweedensis have legs with some reddish colouring basally. P. fuscipes is the only introduced species, and according to Lea (1923) it may be possible that P. tweedensis is actually that European species.
Late March 2016
Buckland
Late December 2014
Buckland
On the bank of a creek.
Late May 2012
Buckland
On the bank of a creek.
Late December 2013
Spring Beach
Late January 2018
Almo River Reserve, Kindred
Next to the Forth River
