Thrips nigropilosus Uzel

Mound, Laurence A. & Masumoto, Masami, 2005, The genus Thrips (Thysanoptera, Thripidae) in Australia, New Caledonia and New Zealand, Zootaxa 1020 (1), pp. 1-64 : 37-38

Thrips nigropilosus Uzel

Thrips nigropilosus Uzel, 1895: 198

Diagnosis: Macropterous or micropterous. Body and legs largely yellow, light brown shadings on thorax and medially on tergites I–VI; major setae brown; antennal segment I yellow, II light brown, III ­ VII brown; forewings pale with very faint shading on clavus and at veinal fork. Antennae 7­segmented; ocellar setae pair III stout, arising lateral to first ocellus; postocular setae I slightly longer than III, setae II minute. Pronotum with transverse lines of sculpture weak, 16–20 discal setae all relatively long, also anteromarginal, antero­angular, midlateral and posteromarginal setae S1 unusually long and dark. Mesonotum with campaniform sensilla present or absent. Metanotum with irregular reticulation ( Fig. 60 ); median setae arising behind anterior margin, campaniform sensilla present or absent. Forewing first vein (when present) with 3 setae on distal half, wings variably reduced in length, sometimes no longer than width of pterothorax. Tergite II with 3 lateral marginal setae; tergites II–VII with lines of sculpture between median setal pair, these setae variable in length but usually more than half as long as their tergite ( Fig. 61 ); posterior margin of tergite VIII with complete comb of slender microtrichia; pleurotergites and sternites without discal setae. Male smaller than female, sternites III–VII with transverse glandular area.

Breeding: A leaf feeding polyphage, this species has been considered a pest of cultivated Pyrethrum in the highlands of Kenya, also of Chrysanthemum and lettuce under glass in Europe, and of Chrysanthemum in Japan. A substantial population was found on a garden Achillea species at Gosford, New South Wales. This is an unusual Thrips species , in that the wing condition varies from fully macropterous to micropterous. Males are always short winged, but females are more commonly long winged under long day lengths and short winged under short day lengths ( Nakao, 1993).

Distribution: Widespread in temperate countries around the world, including New Zealand, this species is also found in the cooler parts of tropical countries such as Kenya and Tanzania. In Australia, populations have been seen from near Adelaide and also from Gosford, north of Sydney.

Relationships: The abdominal chaetotaxy and ctenidia of this species are typical of Thrips , with S3 small on tergites VI–VIII despite S1 and S2 being unusually large, as might be expected in a species that exhibits microptery. However, even fully winged females have the pronotal anteromarginal and midlateral setae exceptionally long. The

only described member of the genus with which T. nigropilosus might usefully be compared is a little known Indian species, T. garuda Bhatti , in which the metanotal structure as well as the general body colour and chaetotaxy are similar.

Figures

FIGURES 60–71. Thrips species. T. nigropilosus 60–61: (60) Meso­metanota; (61) Tergites III–IV. T. novocaledonensis 62–63: (62) Meso­metanota; (63) Tergites & pleurotergites IV–V. T. obscuratus 64–67: (64) Head & pronotum; (65) Meso­metanota; (66) Tergites & pleurotergites III–IV; (67) Tergites VII–VIII. T.orientalis 68–69: (68) Meso­metanota; (69) Forewing clavus. T. pallisetis 70–71: (70) Meso­metanota; (71) Tergites VII–X.