प्रारम्भिक कीट विज्ञान/२१
THYSANOPTERA-THRIPIDAE THYSANOPTERA Synonyms : Physopoda Etymology : Thysano - fringe; ptera - wings Common name : Thrips.
Characters They are minute, slender, soft bodied insects.
Mouthparts are rasping and sucking. Mouth cone is formed by the labrum and labium together with basal segments of maxillae. There are three stylets derived from two maxillae and left mandibles. Right mandible is absent. Hence mouthparts are asymmetrical.
Wings are either absent or long, narrow and fringed with hairs which increase the surface area. They are weak fliers and passive flight in wind is common.
Tarsus is with one or two segments. At the apex of each tarsus a protrusible vesicle is present.
Abdomen is often pointed. An appendicular ovipositor may be present or absent.
Nymphal stage is followed by prepupal and pupal stages which are analogous to the pupae of endopterygote insects.
Classification: This order is subdivided into two suborders.
1. TEREBRANTIA: Female with an appendicular ovipositor. Wing venation is present.
2. TUBULIFERA: Ovipositor is absent. The abdomen is tubular. Wing venation is absent.
Importance They suck the plant sap. Some are vectors of plant diseases. Few are predators. e.g. Rice thrips: Stenchaetothrips biformis is a pest in rice nursery.