Icerya Signoret

Watson, Gillian W., 2022, Towards identification of the scale insects (Hemiptera: Coccomorpha) of continental Africa: 2. Checklists and keys to six archaeococcoid families, Zootaxa 5105 (3), pp. 301-356 : 334

Genus Icerya Signoret

Icerya is a tropical to subtropical genus of 38 species, five of which have been recorded from continental Africa ( García Morales et al. 2016). They are relatively large insects ( Fig. 10 ), so heavy infestations extract significant volumes of sap and can cause drying of tissues, premature leaf drop, sooty mould growth and reduction in fruit harvests. Woody hosts are preferred, and the insects feed on stems and leaf veins rather than on the leaf lamella ( Kondo & Watson 2022 in press).

Key to adult females of species of Icerya in continental Africa, derived from Unruh and Gullan (2008). See Figs 10 and 22 . Icerya corticalis is not included because it is known only from males.

1(0) Setae on abdominal margin black in slide mount. Abdominal spiracles numbering 2 pairs. Open-centre pores present.................................................................................................... purchasi

- Setae on abdominal margin stained red in slide mount. Abdominal spiracles numbering 3 pairs. Open-centre pores present or absent.............................................................................................. 2

2(1) Open-centre pores present.............................................................................. 3

- Open-centre pores absent...................................................................... aegyptiaca

3(2) Ovisac band present. Each open centre pore with a spur on inner edge of rim ( Fig. 22 ). Open-centre pores present around margin and often forming short transverse rows across parts of dorsum............................... seychellarum ( Fig. 10 )

- Ovisac band absent. Each open centre pore without a spur on inner edge of rim ( Fig. 22 ). Open-centre pores generally restricted to margins, not forming transverse rows on dorsum................................................... natalensis

Figures

FIGURE 10. Icerya seychellarum Westwood, adult female, from Williams & Watson (1990: 24, Fig. 5), reproduced with permission of the authors and CABI.

FIGURE 22. Gigantococcus and Icerya pores from Unruh & Gullan (2008: 16-18, parts of Table 2), © Magnolia Press, www. mapress.com/j/zt, reproduced with permission of the copyright holder.