Liothrips Uzel

(Figs 52, 53, 67)

Liothrips Uzel, 1895: 261 . Type species: Phloeothrips setinodis Reuter, by subsequent designation.

The largest genus in the subfamily Phlaeothripinae, this genus comprises 283 named species from around the world. Three subgenera have been proposed, of which Epiliothrips includes just two species from Africa, and Zopyrothrips 25 species from Southeast Asia. Mirab-Balou et al. (2011) list 25 species of Liothrips from China, and zur Strassen (1994) lists 74 species from Indonesia. However, species identification in this genus is very difficult. The only available identification key (Priesner 1953) is unreliable and misleading, having been based largely on slides prepared by H. Karny who mounted each specimen ventral-side uppermost. According to that key, some plant genera such as Piper and Schlefflera share a surprisingly large number of Liothrips species. In order to to establish a reliable basis for species recognition in this genus, studies are needed on variation in body size, structure and setal lengths within and between populations on single plant species.

Diagnosis: Head longer than wide (Fig. 67); postocular setae well-developed; stylets retracted into head, variable in length; antennae 8-segmented, III with 1 sensorium, IV with 3; pronotum with 5 pairs of well-developed setae (am sometimes small), notopleural sutures complete; basantra absent; mesopresternum transverse or eroded medially; sternopleural sutures present (Fig. 52); fore tarsal tooth absent in both sexes; fore wings parallel-sided, with duplicated cilia (Fig. 53); pelta triangular; tergites II–VII with 2 pairs of wing-retaining setae; tube with straight sides, usually shorter than head; male sternite VIII usually with an entire pore plate.