Key to Scirtothrips species from Lord Howe Island

1. Pronotum closely striate, striae separated by no more than base of a discal seta (Fig. 14); ocellar region transversely striate, setae pair III arising close to anterolateral sides of triangle; metanotal median setae arising at anterior margin; fore wing second vein with 3–8 setae; antennal segment III more than twice as long as wide............................. albomaculatus

-. Pronotum broadly striate, striae wider apart than base of any discal seta (Figs 15, 16); ocellar region without or with very weak striae, setae pair III arising between or behind midpoints of hind ocelli; metanotal median setae arising behind anterior margin (Fig. 17); fore wing second vein with 4 (or 3) widely spaced setae; antennal segment III slightly less than 2.0 times as long as wide............................................................................................... 2

2. Body pale brown; tergites II–VII lateral thirds with up to 10 transverse sculpture lines each bearing many microtrichia (Figs 18, 19); sternites with numerous microtrichia lateral to marginal setae pair S2 (Fig. 20); ocellar triangle with no sculpture lines (Fig. 15)................................................................................. cyatheae sp.n.

- Body yellow, only distal antennal segments brown; tergites II–VII without microtrichia on transverse sculpture lines (Figs 21, 22); sternites without microtrichia, or with a few lateral to marginal setae pair S3; ocellar triangle with faint irregular reticulation (Fig. 16)......................................................................... gymnos sp.n.