|July 2013. A request from India for the confirmation that the photo is showing a species of Ceroplastes, and help in the identification of a caterpillar, both on mango.
A member wrote: Order Hemiptera: Suborder Sternorrhyncha: Superfamily Coccoidea: Family Coccidae: Genus Ceroplastes. The specimen is unlikely to be C. cirripediformis, as this species has never been recorded from India. Ten species of Ceroplastesoccur in India and they are very difficult to identify, even in slide mounts examined at very high magnification. Accurate identification to species level mostly is not possible from photographs. On the basis of appearance, you do not have C. stellifer. It could be one of: C. actiniformis, C. ajmerensis, C. alami, C. ceriferus, C. destructor, C. floridensis, C. pseudoceriferus, C. rubens or C. stipulaeformis.
Of these species, the following have been recorded feeding on mango before: C. actiniformis, C. ceriferus, C. floridensis, C. pseudoceriferusorC. rubens. C. stelliferalso feeds on mango, but your specimen is definitely not this species.
As for the caterpillars, they are partly grown caterpillars of a limacodid moth, Parasa lepida lepida(Cramer), which is widespread, polyphagous and reported from mango. As they mature, the projecting spine-covered scoli will become shorter, until they resemble the usual published illustrations of P. lepida(see http://www.nbaii.res.in/insectpests/Parasa-lepida.php).