Thripidae: Sericothripinae

Biology

Sericothripine species breed either in flowers or on leaves, the precise biology of most species remaining unknown and possibly being variable. The European species Neohydatothrips gracilicornis is generally considered specific to Fabaceae such as Vicia cracca, but it has also been reported causing damage to the needles of Pinus in Italy and Spain (Marullo, 1990). N. samayunkur is now widespread around the world as a pest of the leaves and flowers of cultivated marigold plants in the genus Tagetes.

Diversity

Currently only three genera are recognised for the 140 species in this subfamily, although the phylogenetic significance of these genera remains in doubt. This situation has been discussed, together with keys to genera and some species, by Mound & Marullo (1996) and Mound & Tree (2009). Sericothrips includes all of the species in the group that are known to produce short-winged adults, whereas the species in the other two genera are always fully winged. Hydatothrips and Neohydatothrips are distinguished from each other by whether or not the metasternum anterior margin is deeply excavate, but this distinction involves some species that are intermediate in condition. The abdominal tergites have closely spaced rows of microtrichia laterally, the abdominal dorsoventral muscles insert onto distinctive plates on the tergites and sternites, the forewing first vein has a complete row of setae but the second vein has no setae, and the larvae have distinctive expanded and fringed major setae. Moreover, in almost all of the species the major sensorium on the sixth antennal segment has a very long and narrow base, such that in face-view the segment appears to have a longitudinal suture.

Distribution

Although most species in this subfamily are found in the tropics and subtropics, a considerable number of species are found in the northern and southern hemisphere temperate zones. In Australia, one species-group has radiated in association with the genus Parsonsia (Apocynaceae), but almost nothing is known of the biology of the many Neotropical species.

Sericothripinae Keys

Subfamilies A-Z