Ceroplastes rusci (Linnaeus, 1758)

Pellizzari, Giuseppina, Rainato, Alessio & Stathas, George J., 2010, Description of the immature female instars of Ceroplastes rusci (Linnaeus) (Hemiptera: Coccidae), Zootaxa 2556 (1), pp. 40-50 : 48

Key to immature instars of C. rusci

Usually male 2 nd -instar nymphs are intermingled with female 2 nd -instar nymphs on the host plant. For this reason, the following key also includes 2 nd -instar males.

1 With 3 stigmatic spines in each stigmatic cleft ............................................................................................................ 2

- With more than 3 stigmatic spines in each stigmatic cleft............................................................................................ 4

2 With 3 or 4 spiracular disc-pores in each spiracular pore band, each with 3 loculi; stigmatic spines subequal in size, usually globular or bullet-like; claw digitules both slender ...............................................................first-instar nymph

- With 4–7 spiracular disc-pores in each spiracular pore band, each mainly with 5 loculi; stigmatic spines conical, median stigmatic spine distinctly longer than other two; claw digitules dissimilar, one broad and other slender ...... 3

3 Ventral tubular ducts present in a single row of 28–30 ducts around body margin, except posterior 1/3 of margin. .... ................................................................................................................................................................. 2 nd instar male

- Ventral tubular ducts absent ................................................................................................................. 2 nd instar female

4 With 7–11 spiracular disc-pores in each spiracular pore band; each stigmatic cleft with 7 or 8 stigmatic spines. Pregenital disc-pores absent ...................................................................................................................... 3rd instar female

- With an average of 60 spiracular disc-pores in each spiracular pore band; each stigmatic cleft with about 20 stigmatic spines. Pregenital disc-pores present................................................................................................adult female