Exothrips sacchari (Moulton)

Mound, Laurence A., 2011, Grass-dependent Thysanoptera of the family Thripidae from Australia, Zootaxa 3064 (1), pp. 1-40 : 18-20

Exothrips sacchari (Moulton)

( Fig. 38 )

Anaphothrips sacchari Moulton, 1936: 265

This species, known previously only from a single female taken at Victorias, Philippines, is identified here from Australia based on the redescriptions of the holotype by Bhatti (1975) and Reyes (1994). Antennal segment VI of the holotype was described as brown with the base paler. In a series of six females from Sorghum flowers at Kununurra, Western Australia, three have antennal segment VI dark brown with V medium brown, and three have VI pale in the basal half, and V largely pale; two males collected with these females have the antennae almost uniformly pale. In a series of 11 females taken from grass flowers at Litchfield, near Darwin in Northern Territory, antennal segment VI is consistently paler at the base than medially, with V very pale brown, and three males taken with these females have pale antennae. The colour of the antennal segments in sacchari is here considered to be variable.

The males taken in Australia in association with sacchari females lack a tooth on the fore tibia. This condition is shared with the Indian species sakimurai, although that species has the metanotal median pair of setae arising close to the lateral pair. Also similar is hemavarna, a species that is widespread across India, but the males of that species have a stout tooth on the fore tibia, and a transverse row of microtrichia on sternites VII–VIII. The two males from Sorghum at Kununurra have no sternal microtrichia, but the three males taken at Litchfield have a transverse row of microtrichia on sternites VII–VIII that varies from weakly to strongly developed, and two males taken in Brisbane Forest Park with four females are similar to these. On the head, the setae of postocular pair I are minute and wide apart, a condition shared with hemavarna (see Bhatti, 1975), but ocellar setae pair III vary in position from just in front of, to just behind the tangent between the anterior margins of the posterior ocelli ( Fig. 38 ); moreover, the position of these two setae is often asymmetric. A few males from near Darwin, and also from Brisbane, have the craspedum on tergites VI–VII more or less dentate laterally, but the craspedum is smooth laterally in the males from Kununurra and also in some males from other northern localities. At present it seems best to consider all of these Australian specimens as conspecific under the name sacchari .

Figures

FIGURES 38 – 45. Grass living Thripinae. (38) Exothrips sacchari, head. Parexothrips palumae 39 – 44: (39) head; (40) female sternites VI – VII; (41) tergites VI – VII; (42) tergites VII-IX; (43) meso & metanota; (44) prosternum. (45) Caprithrips insularis, prosternum.