Crawlers are 0.3 mm long. Immature and newly matured females have yellowish bodies dusted with mealy white wax that is often thinner between the segments, giving the body a slightly barred appearance. Short, waxy filaments develop around the margin in the adult female, each less than a quarter as long as the body. The adult female is 2.0-3.5 mm long, soft-bodied, elongate oval and slightly flattened;on maturation she begins to secrete sticky, elastic, white wax filaments from the edges of her abdomen to form a protective ovisac for her yellow eggs. The ovisac can be as much as twice as long as the body, or more (Miller et al., 1999). Sometimes the body colour of the mature female is not immediately apparent if she has become buried under white ovisac material. The male is a short-lived, small insect with long, segmented antennae;six legs each bearing a single claw;one pair of simple wings coated with white wax powder;a pair of long, white waxy filaments at the posterior of the abdomen;and no mouthparts. Live specimens have yellow body contents;within 24 hours of death, the body contents characteristically darken to grey or black.
Related invasive species
- Paracoccus marginatus
Related Farm Practice
- Thinning
- Development
- Canning
- Protection
Paracoccus marginatus is a mealybug native to Central America. It has been spread accidentally outside its native range by trade in live plant material, such as papaya fruits. It became an invasive pest in the Caribbean Islands and USA (Florida) in 1994-2002;the West and Central Pacific islands in 2002-2006;South-East Asia and the Indo-Pacific islands in 2008-2010;West Africa in 2010-2016;East Africa from 2015;and Israel in 2016. The pest is expected to continue spreading, and climate warming is likely to increase the areas where it can establish. It is is polyphagous and spreads rapidly, forming heavy infestations on aerial plant parts and killing some host-plants, including papaya. It poses a threat to commercial papaya plantations.
Heavy infestations by P. marginatus cause stunting and deformation of new growth, leaf yellowing, leaf curl and early fruit drop (Anon., 2000). Fruit may become completely covered by a layer of mealybugs and wax secretions (Miller et al., 1999), and papaya fruit tissue underneath the mealybug colonies becomes hard and bitter. Papaya, hibiscus and annona species are particularly badly affected.
The species was described from material collected on cassava and papaya, but P. marginatus is now recognized to be highly polyphagous, attacking vegetables and fruits as well as ornamental plants belonging to 136 genera in 49 plant families (García Morales et al., 2019). It causes significant damage to cassava in Central America. Papaya, hibiscus and annona species are particularly badly affected (Matile-Ferrero et al., 2001). Papaya is a preferred host.