Figs. 14-17. Austroperla cyrene (Newmann, 1845) (Austroperlidae). Details of the arculus, all dorsal view. 14. Left forewing; the arrow indicates the arculus, usual morphology. 15. Right forewing, same individual as in 14; the left arrow indicates the base of the arculus, i.e. the first cross-vein between M and Cu(A), basal to the base of CuA (itself indicated by the right arrow). 16. Left forewing; the left arrow indicates a vestigial crossveins directed towards the arculus (itself indicated by the right arrow). 17. Right forewing, same individual as in 16; the left arrow indicates a vestigial cross-vein occurring basal to the arculus (itself indicated by the right arrow); the arculus is reticulated.