Du Toit, G.D.G. 1975 Notes on the biology and behaviour of Sphaeraspis prieskaensis Jak. (Hemiptera: Coccoidea) a pest on grape vine roots.. Proceedings of the First Congress of the Entomological Society of Southern Africa, Stellenbosch, 1974. Entomological Society of Southern Africa Pretoria 273 pp.
Notes: The biology of Sphaeraspis prieskaensis Jakubski, a pest of sultana grape-vines along the lower Orange river, South Africa, is described from observations there in 1960-62. Eggs were laid in spring in the soil close to the vine roots at a depth of about 50 cm. Newly hatched larvae attached themselves to the roots by their mouthparts, became sessile and secreted a waxy material to form pearl-like cysts. The second larval or cyst stage had two phases, a feeding and growing one followed by a non-feeding one. Once the first phase was completed, the margarodid could remain inactive in the soil for a long period. The species is paedogenetic, and sexually mature females and male prepupae emerged from the cysts. The larviform females with fossorial legs made their way upwards through the soil in mid-July just after the lowest subterranean winter temperatures of 6-7 deg C. Males underwent complete metamorphosis, pupating just below the soil surface in early May when temperatures were about 16 deg C. After mating, which was usually completed by early September, females burrowed into the soil and oviposition took place. The peak period for oviposition was from the end of October to the beginning of November. Symptoms displayed by an infested vineyard were similar to those caused by phylloxera (Viteus vitifoliae (Fitch)).