Simple technique based on taxonomic characters for distinguishing the cotton mealybugs (Pseudococcidae: Homoptera)

Adult males of P. solenopsis, P. solani and M. hirsutus possessed black, brown and pink coloration on their head, respectively. The long waxy anal filaments were observed in females of P. solenopsis followed with P. solani and M. hirsutus. Besides, a distorted black marking as “horse shoe shape” in P. solenopsis another prominent and almost regular black marking was present on the ventral side of abdomen of P. solani. These markings were invisible in M. hirsutus. Observations revealed that neither P. solani nor P. solenopsis possessed true ovisac unlike in M. hirsutus. Smaller size of loose sac attached to the female of P. solani was observed some times while larger in case of P. solenopsis, which contained crawlers. Body fluid colour of P. solenopsis, P. solani and M. hirsutus was noted as yellowish green, brownish green and pink, respectively. Elliptical cocoon produced males with black colour head, elongated and pointed cocoons at anterior end gave rise males with brown head, and produced globular prominent white cocoon forms in P. solenopsis, P. solani and M. hirsutus, respectively. Important taxonomic characters viz; presence of flacid circulus, nine segmented antennae and translucent pores on hind femur and tibia in P. solenopsis while rod shaped circulus, eight antennal segments and translucent pores on hind tibia of P. solani were matched with the field characters of each species. No hind femur and tibial translucent pores were seen in M. hirsutus while nine antennal segments and a goggle shaped circulus was present. Interestingly, circulus was observed in 2^nd and 3^rd instars of both the sexes and adult females while absent in 1^st instars as well as in 4^th instar male (pupa) and adult males, irrespective of species.