Key to Horistothrips species

1. Pelta occupying no more than 60% of anterior margin of abdominal tergite II (Fig. 4); postocular setae about 1.5 times as long as width of antennal segment II; male glandular area transverse across sternite VIII ............................................................................................................................................... australiae

-. Pelta occupying more than 80% of anterior margin of abdominal tergite II (Fig. 8); postocular setae scarcely 1.2 times as long as width of antennal segment II; male glandular area on sternite VIII transversely oval ................................................................................................................................. platygaster