Gigantococcus Pesson & Bielenin

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 : 333

Genus Gigantococcus Pesson & Bielenin

Gigantococcus is an African genus of 19 described species, 13 of which occur in eastern Africa ( García Morales et al. 2016). Woody hosts are preferred. They are relatively large insects ( Fig. 14 ) so heavy infestations extract significant volumes of sap and can cause drying of tissues, premature leaf drop, honeydew fouling, sooty mould growth and reduction in fruit harvests ( Kinuthia & Mwangi 1988). It is possible that “ Steatococcus ” hystrix may belong in Gigantococcus (see comments below).

Key to most of the species of Gigantococcus found in continental Africa, from Unruh and Gullan (2008). See Figs 14 and 22.

1(0) Ovisac band present. Marsupium absent................................................................... 2

- Ovisac band absent. Marsupium present or absent........................................................... 8

2(1) Adult female very large (> 8 mm long,> 5 mm wide). Simple multilocular pores in ovisac band each with a quadrilocular or quinquelocular centre........................................................................... maximus

- Adult female not especially large (4–6 mm long, 3–5 mm wide). Simple multilocular pores in ovisac band each with a bilocular or trilocular centre.................................................................................... 3

3(2) Inner ovisac band composed of simple multilocular pores, each with a bilocular centre only. Compound multilocular pores, each with a quadrilocular or quinquelocular centre and 8–12 rectangular outer loculi, present on ventral derm. Wax white, quite long and rather wispy on posterior margin................................................ bimaculatus ( Fig. 14 )

- Inner ovisac band composed of simple multilocular pores, each with a trilocular centre. Compound multilocular pores, each with a quadrilocular or quinquelocular centre and 8–12 rectangular outer loculi, absent. Wax colour and texture various... 4

4(3) Ventral surface with compound pores, each with an 8‒12-lobed centre and 6–8 elongate reniform outer loculi........... 5

- Compound pores with this structure absent................................................................. 7

5(4) Head and thorax with compound pores forming marginal clusters, each pore with a large trilocular centre and 6–8 reniform outer loculi.......................................................................................... 6

- Compound pores with this structure absent........................................................ schoutedeni

6(5) Head and thorax with marginal clusters each of 3 or 4 compound pores. Wax yellow and white................ alboluteus

- Head and thorax with compound pores occurring singly and in pairs. Wax pale yellow....................... pattersoni

7(6) Dorsal surface covered with pores of 2 types: simple multilocular pores, each with a trilocular centre and 6–9 evenly distributed outer loculi, not elongate in profile ( Fig. 22 ); and distinctive compound multilocular pores, each with a 6-lobed centre and 6–8 elongate, slightly reniform, outer loculi ( Fig. 22 ). Wax white....................................... nigroareolatus

- Dorsal surface covered with pores of 1 type: multilocular pores, each with a trilocular centre, 3 pairs of outer loculi and a distinctive elongate profile ( Fig. 22 ). Compound multilocular pores with this structure absent. Wax white....... brachystegiae

8(1) Marsupial band forming a sclerotized V shape with lateral wings. Dorsum with large multilocular pores, each 17–20 μm in diameter, with a trilocular (sometimes bilocular) centre and 4–6 outer loculi (arranged in pairs).............. theobromae

- Marsupial band forming a sclerotized semicircle. Dorsum with small multilocular pores, each 10–12 μm in diameter, with a trilocular centre and 6–9 outer loculi (not arranged in pairs)................................................... 9

9(8) Setae on most antennal segments and around margin very long, each up to 1500 μm long.................................................................................................... gowdeyi , madagascariensis, bicolor

- Setae on antennae and around margin only 900–1000 μm long..................... caudatus , euphorbiae , longisetosus

Figures

FIGURE 14. Gigantococcus bimaculatus De Lotto, adult female, from De Lotto (1959: 386, Fig.1), reproduced with permission of the Entomological Society of Southern Africa.

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.