Green spruce gall louse
| Green spruce gall louse | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Systematics | ||||||||||
|
||||||||||
| Scientific name | ||||||||||
| Sacchiphantes viridis | ||||||||||
| ( Ratzeburg , 1843) |
The green spruce gall louse ( Sacchiphantes viridis ) is a gall-forming aphid with a biennial, pentamorphic (five different morphs), Hererözischen (two different hosts) holocycle (alternation between parthenogenic and bisexual reproduction). Their primary host is the spruce, the secondary host is the larch.
features
The green spruce gall louse has five different types of morphine. Two of them are winged.
Symptoms of the host plants: Pineapple-shaped galls form on the spruce due to the suckling activity of the generation of emigrants. The needles of the larch turn yellow at the suction point and bend off.
distribution
The green spruce gall louse occurs where its two hosts, spruce and larch, occur together. Their original range are the Alps.
Life cycle
In spring, the Fundatrix lays its eggs on the spruce. The sucking activities of the hatched lice form a bile in which they spend the still wingless larval stages. Before adult molt, the emigrants leave the gall. After molting, they fly out and lay eggs on a larch. The hatched young hibernate there under bud and bark scales. In spring they complete their development as wingless adults and in turn lay eggs themselves at the base of fresh shoot buds. This results in either more wingless spring generations or so-called remigrants who fly back to spruce trees. The remigrants lay eggs on spruce trees, from which sexualis hatch. A sexual female lays exactly one egg from which a fundatrix hatches. This hibernates and the cycle begins again.
Individual evidence
- ↑ a b Forest Health Diagnostic Program. Beat Wermelinger. WSL - Forest Protection Switzerland. October 19, 2010. Retrieved August 10, 2013.
- ↑ Sacchiphantes viridis - Green spruce gall louse. ( Memento from July 25, 2008 in the Internet Archive ) Online reference work by Werner Heitland. May 5, 2002. Accessed August 10, 2013.
