Genetical studies of the lady-bird beetle, Harmonia axyridis Pallas (Report VIII)

Abstract

1. In this report two subtypes of succinea, succinea-7 (Figs. 1-5) and succinea-8 (Figs. 6-8), and three subtypes of axyridis, axyridis-4 (Figs. 9-11), axyridis-5 (Figs. 12-14) and axyridis-6 (Figs. 15, 16), are dealt with. Each of these subtypes is due to a factor (p⁷=factor for succinea-7, p⁸=factor for succinea-8, P^A-4=factor for axyridis-4, P^A-5=factor for axuridis-5 and P^A-6=factor for axyridis- 6) belonging to the same allelomorphic series as conspicua (P^C), gutta (P^G), distincta (P^D), transversifascia (P^T), spectabilis (P^S), rostrata (P^R), axyridis-1 (P^A-1), axuridis-2 (P^A-2), axyridis-3 (P^A-3), forficula (P^F), aulica-1 (P^Au-1), aulica-2 (P^Au-2), succinea-1 (p¹), succinea-2 (p²), succinea-3 (p³), succinea-4 (p⁴), succinea-5 (p⁵) and succinea-6 (p⁶).
2. The homozygoue of succinea-8 is missing. This gene apparently has a lethal effect in the homozygous state, or else it is closely linked with a lethal gene.
3. Eight subtypes can be distinguished among succinea, which are characterized by the mode of appearance, disappearance or confluence of individual spots.
4. Six subtypes can be distinguished among axyridis bred at 30°C; they are characterized by the configuration of individual orange spots.