February 2004. Is there a way to distinguish between Planococcus minor, P. lilacinus and P. citri externally, based on gross morphology, asked a member from India. And, among the three species, which are the species that reproduce viviparously and do not produce an ovisac?
Planococcus lilacinus can be distinguished from the other species by its mauve/lilac body colour (visible in life if not too much wax present; otherwise visible when insect is squashed on white paper). The other species have yellowy pink body contents.
Apparently P. lilacinus is not found above 1000 m. On cacao, ants are necessary for development of colonies of P. lilacinus; in Sri Lanka, this species is thought to be a vector of Ceylon Cocoa Virus disease (CCV). Reproduction is known to be sexual and that the species is ovoviviparous.
There is no reliable way to tell the difference between P. citri and P. minor in life – indeed they are extremely difficult to separate with confidence even when slide-mounted and studied under phase contrast illumination!
In terms of hosts, P. minor may prefer cacao more than P. citri. Similarly, although both species occur on citrus, this is the preferred host plant for P. citri and is seldom used by P. minor.
P. citri is known to reproduce sexually. There is no mention of the biology of P. minor in the literature, but on the basis of the number of ducts and pores present, it seems likely that this species also reproduces sexually.
All three species are capable of producing a small ovisac.