(Thysanoptera: Thripidae)
Issue No. 172
H. A. Denmark
Introduction
Reuter (1891) first described this thrips from specimens taken in a greenhouse at Helsingfor, Finland. Bagnall (1932) transferred Heliothrips femoralis to Hercinothrips. White (1916) found large numbers of this thrips infesting a number of plants, but were mainly confined to sugar-beet seedlings in greenhouses in Washington, D. C, White referred to this pest as the sugar-beet thrips and did a life history study with an average mean temperature of 73F and found that it took about 30 days from egg to adult. The greenhouse thrips, Heliothrips haemorrhoidalis (Bouche), and the banded greenhouse thrips were both reduced in numbers below the economic threshold for several years following the medfly sprays in Florida in 1956-58, both species presently are increasing, particularly under greenhouse conditions.