Porismus McLachlan, 1867

(Figs 24–26)

Type species. Osmylus strigatus Burmeister, 1839: 184 (by monotypy).

Diagnosis. Wings with highly distinctive contrasting colour pattern; wings ovoid; body glossy black with head bright orange; RP with numerous crossveins irregularly arranged; CuA and CuP strongly sinuous in both wings, branching near wing margin in FW; HW CuA with few dichotomous branches; female forecoxa with 11–15 short pedicellate setae and a prominent preapical process on dorsal surface; female tergite 9 strongly produced posteroventrally; sternite 8 with posterior end forked and with two small setose lobes; spermathecae rounded.

Comments. Commonly called the ‘pied lacewing’ this highly distinctive species is placed in a separate subfamily based on a series of autapomorphies features in the wings such as the branching pattern of medial and cubital veins, lack of gradate series crossveins and multiple sc-r crossveins. Porismus strigatus is associated with Eucalyotus trees during the autumn months in eastern Australia when adults have been observed ovipositing under tree bark; larvae are sub-corticolous on these trees and not associated with riparian habitats (Winterton et al., 2017). Krüger (1913) erected Porisminae along with Eidoporisminae as separate subfamilies based on distinctive venational characters, and although the male and female abdominal sclerites and genitalic morphology reflect a close relationship with Stenosmylinae, their status as separate subfamilies is maintained (discussed in New, 1983b). Winterton et al. (2017 a,b) also concluded that Porisminae was closely related to Eidoporisminae and Stenosmylinae, consistent with previous proposals (Esben-Petersen, 1917, Kimmins, 1940, New, 1983b), but relationships amongst the three subfamilies were inconclusive.