Fenusa Pusilla (Noun)
Meaning
Small black sawfly native to Europe but established in eastern United States; larvae mine the leaves of birches causing serious defoliation.
Classification
Nouns denoting animals.
Examples
- Fenusa pustula was formerly known as Fenusa pusilla and can still be referred to as such in some older literature.
- In Europe the primary hosts for the Fenusa pusilla larvae are white and paper birch trees, whereas in the northeastern US downy and yellow birch are favored.
- Although first discovered in North America in 1923 in Ontario the Fenusa pusilla had established a healthy presence by 1995 throughout eastern US states such as Pennsylvania, Ohio and Maine.
- Severe Fenusa pusilla outbreaks have been observed on isolated trees for example in areas such as the Green Mountains of Vermont, although this typically only occurs at intervals of 10 years or so.
- Fenusa pusilla larvae overwinter in protected areas as fourth instar larvae and emerge in the following spring to continue feeding and complete development.