A. atratus puparia are elliptical, black, 1.0-1.1 mm long with a long marginal white wax fringe and dorsal wax filaments that often completely cover the insect. The puparia often occur in dense colonies that smother the underside of the fronds with puparia, wax secretions and honeydew, on which sooty moulds grow.
Eggs and larvae of A. atratus occur on the underside of palm fronds, and when abundant they are highly conspicuous due to the flocculent white wax which covers the pupae. Adult whitefly may be found on both upper and lower surfaces of palm fronds. The upper surfaces of infested fronds often exhibit chlorosis or necrosis. Infested palms may also exhibit wilting and a covering of sticky honeydew and associated sooty moulds.
However, field identification of A. atratus is unreliable as there are similar species with black pupae in the genus Aleurotrachelus and other genera such as Aleurotulus, Aleurolobus and Tetraleurodes.
Related invasive species
- Aleurotrachelus atratus
Related Farm Practice
- Host plants
- Hosts
- Feeding
The whitefly A. atratus is a highly invasive pest of coconut and ornamental palms (Arecaceae). Before the 1990s this species was only known to feed on coconut from Brazil (Hempel, 1922;Mound and Halsey, 1978), but since 2001 it has been reported widely in the tropics and subtropics on more than a hundred plant species and is known to be invasive in Cape Verde, Comoros, Mauritius, Mozambique and the Seychelles. Mainly thelytokous, it is oligophagous on perennial palms, and has winged adults, all of which allows it to naturalize in new areas after accidental introduction on host plant material. It has also been found on indoor plantings of palms in botanical collections in temperate regions (Malumphy and Tresedar, 2011). The biology, host range and increasing geographical distribution of A. atratus have been studied in detail by Borowiec et al. (2010), and reviewed by Malumphy and Tresedar (2011).
The upper surfaces of infested palm fronds often exhibit chlorosis and/or necrosis. The undersurfaces of infested fronds will be covered in dense patches of black puparia covered in conspicuous white wax secretions. The foliage, stems and fruit may be covered with sticky honeydew which serves as a medium for the growth of sooty moulds. Large whitefly infestations may cause wilting and the plant may lose vigour;consequently, there may be a decrease in fruit production.
A. atratus has been recorded feeding on 114 host plant species belonging to five families. Most (96%) hosts are palms in the family Arecaceae. Coconut is the most commonly reported host. A. atratus is occasionally recorded on non-palm hosts, including two highly important crops, citrus and aubergine. The significance of A. atratus on non-palm hosts, however, is unclear (Malumphy and Tresedar, 2011).