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Ceratovacuna lanigeraSugarcane woolly aphidOn this page: Identification & Distribution Other aphids on the same host Damage & ControlIdentification & DistributionAll populations of Ceratovacuna lanigera are thought to be anholocyclic on the secondary host (grasses). Adult apterae of Ceratovacuna lanigera (see first picture below) are pale green or brownish yellow or greyish brown, densely covered with white wax that forms thick columns at margins of body and may become filamentous. The head and prothorax are fused, forming a cephalothorax. The head bears frontal horns (visible on th clarified mount in third picture below) that are acute and divergent. The antennae are 4-5-segmented, and 0.12-0.16 times the body length. The longest hair on antennal segment III is 0.90-1.40 times that segment's basal diameter, and the terminal process is 0.33-0.56 times as long as the base of the last antennal segment. Wax glands, when present on the cephalothoracic region, are located just below the base of antennae and on the posterolateral margin of pronotum. The rostrum reaches the fore-coxae, and the ultimate rostral segment is 0.45-0.55 times the second hind tarsus segment. The abdominal dorsum is pale, and bears some fine irregular sculpturing. Wax glands may be present laterally on the meso- and meta-notum, and are almost always present on tergites I-VII. First tarsal segments have 4-3-2 or 3-3-2 hairs (fore-mid-hind). The siphunculi are on slightly elevated cones. The cauda is transversely oval, bearing 11-12 hairs. The anal plate is bilobed. The body length of adult Ceratovacuna lanigera apterae is 1.4-2.3 mm.
Images above by permission, copyright Sunil Joshi & Poorani, J. Aphids of Karnataka (accessed 12/2/20). Alatae of Ceratovacuna lanigera (see second picture above) have a brown-black head and thorax, and dusky transverse bands on tergites VI-VIII. The frontal horns are short, much reduced from those of apterae. Antennae are 5-segmented, 0.24-0.28 times the body length, with secondary rhinaria distributed 16-25 on segment III, 5-10 on segment IV, and 2-9 on the base of segment V. The terminal process is 0.19-0.21 times the base of the last segment. The siphunculi are pore-like, and the cauda is semi oval. Wings have normal venation, with the media once branched, and a short pterostigma. Young immatures (see second picture below) have little wax dust on the body. Wax filaments develop gradually, and the third instar shows clear intersegmental lines between the wax bands. The fully grown aphid has a totally woolly appearance. Immature alatae often cluster together and produce abundant long filamentous wax (see second image above).
Images above by permission, copyright Sunil Joshi & Poorani, J. Aphids of Karnataka (accessed 12/2/20). As with several other Ceratovacuna species, Ceratovacuna lanigera has only been found on what is thought to be its secondary host, in this case various grasses (Poaceae), especially sugar cane (Saccharum), but also Imperata, Miscanthus, Oplismenus, Pseudechinolaena, & Themeda. Populations appear to be completely anholocyclic, reproducing parthenogenetically throughout the year. Alate sexuparae have been found in a colony on sugar cane in Japan (Kurosu & Aoki, 1986), and some first instar sexual morphs were obtained, but these were thought to be non-functional. Ceratovacuna lanigera are often attended by ants. This species is a serious pest of sugar cane in south-east Asia, and more recently in western and southern India. Sunil Joshi and Viraktamath (2014) review prospects for biological control. The species is currently distributed in India, Nepal, Bangladesh, east and south-east Asia, Fiji and the Solomon Islands. Other aphids on the same host
Damage and controlSunil Joshi and Viraktamath (2014) review its biology, damage caused, and biological control in south India. Copious honeydew excretion often covers the entire upper surface of the leaves, leading to growth of sooty mould. Due to continuous sap-sucking, the crop becomes stunted, and continuous infestation leads to reduction in the length, circumference, weight and sugar content of the stalk. Control has mainly been carried out with insecticides, although there is increased emphasis on the need to develop biological control methods.
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