Heterothera serraria
Observations/month
| Month | 1980–2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | total | |
|---|
| Januar | | | | | | | | | | | | | | | |
| Februar | | | | | | | | | | | | | | | |
| Mars | | | | | | | | | | | | | | | |
| April | | | | | | | | | | | | | | | |
| Mai | | | | | | 1 | | | | | | | | 4 % | |
| Juni | 2 | 1 | 1 | | | 3 | 1 | 2 | 3 | 2 | 1 | 1 | | 63 % | |
| Juli | 1 | 1 | 1 | 2 | 2 | | | | | | | | 1 | 30 % | |
| August | | | | 1 | | | | | | | | | | 4 % | |
| September | | | | | | | | | | | | | | | |
| Oktober | | | | | | | | | | | | | | | |
| November | | | | | | | | | | | | | | | |
| Desember | | | | | | | | | | | | | | | |