Both sexes fully winged. Adult females vary greatly in size and color, probably depending on the temperature during development, from small and whitish yellow to large and brown; ocellar pigment usually grey, never red; fore wings pale. Antennae 7-segmented; segments III & IV each with a short forked sense cone; VII short. Head wider than long; with 2 pairs of ocellar setae; pair III small, arising on anterior margins or just within ocellar triangle; postocular setae pairs I–III about equal to ocellar setae III. Pronotum with 2 pairs of prominent posteroangular setae; posterior margin with 3 (sometimes 4) pairs of setae. Metanotum variable, usually irregularly reticulate medially with lines converging to midpoint at posterior margin; median setae short, arising behind anterior margin; campaniform sensilla absent. Fore wing first vein usually with 4 (varying 2–6) setae on distal half; second vein with about 15 setae. Abdominal tergite II with 3 lateral marginal setae; V–VIII with paired ctenidia, on VIII posteromesad to spiracles; tergite VIII posteromarginal comb complete, microtrichia long and slender; pleurotergites without discal setae, with closely spaced rows of fine ciliate microtrichia. Sternite II with 2 pairs of marginal setae, III–VII with 3 pairs; sternites without discal setae.
Males usually rare; body small and yellow; tergite VIII with marginal comb represented by few irregular microtrichia; sternites III–V with narrow transverse pore plate.
T. tabaci is unusual within the genus in lacking red pigment around the ocelli, and is usually easily recognized by the closely spaced rows of ciliate microtrichia on the pleurotergites. The genus Thrips is the second largest genus in the Thysanoptera, and currently includes, worldwide, about 295 species. All members of the genus lack ocellar setae I on the head, and they all have ctenidia on tergite VIII posteromesad to the spiracles. Other characters, such as number of antennal segments, number of setae on the fore wing veins, and number of discal setae on the sternites are variable between species (Palmer, 1992; Nakahara, 1994; Mound & Masumoto, 2005).
Breeding on leaves and in flowers, with larvae and adults sometimes predatory on leaf mites. Males are usually rare (Nault et al., 2006), but have been studied in good numbers from eastern Mediterranean countries and also from New Zealand. Although particularly abundant on onions, this species is highly polyphagous, breeding on many hosts including monocotyledonous and dicotyledonous plants. It is particularly important as a pest on onions and garlic, but also on Brassica and tobacco crops in parts of Europe, and on various other crops including potatoes and greenhouse plants in different parts of the world. It is also a vector of the Tospovirus, TSWV.
Presumably originally from the eastern Mediterranean, together with its primary host plants, Allium spp, but now cosmopolitan except for the wet tropics.
THRIPIDAE - THRIPINAE
Thrips tabaci Lindeman
Thrips tabaci Lindeman, 1889: 61
Limothrips allii Gillette, 1893: 15
Thrips communis Uzel, 1895: 176
Thrips annulicornis Uzel, 1895: 177
Thrips pulla Uzel, 1895: 177
Thrips obsoleta Uzel. 1895: 187
Thrips bremnerii Moulton, 1907: 59
Parathrips uzeli Karny, 1907: 48
Thrips bicolor Karny, 1907: 49
Thrips brachycephalus Enderlein, 1909: 441
Thrips hololeucus Bagnall, 1914: 24
Thrips adamsoni Bagnall, 1923: 58
Thrips debilis Bagnall, 1923: 60
Thrips mariae Cotte, 1924: 2
Thrips frankeniae Bagnall, 1926: 654
Thrips seminiveus Girault, 1926: 1
Thrips tabaci f. irrorata Priesner, 1927: 436
Thrips tabaci f. atricornis Priesner, 1927: 437
Thrips tabaci f. nigricornis Priesner, 1927: 436
Thrips dorsalis Bagnall, 1927: 576
Thrips shakespearei Girault, 1927: 1
Thrips indigenus Girault, 1929: 29
Thrips dianthi Moulton, 1936: 104
Ramaswamiahiella kallarensis Ananthakrishnan, 1960: 564.
Mound LA & Masumoto M (2005) The genus Thrips (Thysanoptera, Thripidae) in Australia, New Caledonia and New Zealand. Zootaxa 1020: 1–64.
Nakahara S (1994) The genus Thrips Linnaeus (Thysanoptera: Thripidae) of the New World. United States Department of Agriculture. Technical Bulletin 1822: 1–183.
Palmer JM (1992) Thrips (Thysanoptera) from Pakistan to the Pacific: a review. Bulletin of the British Museum (Natural History) Entomology Series 61 (1): 1–76.