Corresponding author: Ron Felix (
Academic editor: Jinze Noordijk
The discovery of
A decade ago, the discovery of
A literature survey revealed that occurrence data from Northern France, Italy, Switzerland, Germany and Eastern Europe were based on very old records and could not be checked. Its presence and/or arrival in the Netherlands therefore seems difficult to relate to its currently known occurance. A source area for this species remains unknown. Although
Subsequently, we concentrated on the trunks themselves to learn more about the behaviour and life cycle of
In this paper we present information on the biology and ecology of
The nature restoration area ‘De Kaaistoep’ lies immediately west of Tilburg in the south of the Netherlands. It is a former agricultural area, belonging to a waterworks company. The actual research site consists of open arable grasslands on poor sandy soil. This open area is bordered by woodland in the west, north and east. In the area itself there are three large and two small artificial pools, a brook and some patches or rows of deciduous trees and shrubs. Almost in the middle of these grasslands there are two rows of Pedunculate oaks, the trunks of which were investigated. One short row (A) runs from north-north-west to south-south-east and numbers seven oaks. Another, longer, row (B) runs from south-west to north-east and numbers 19 oaks. Some of the trees in row B stand alone, this means that their crowns do not touch other trees. Most of the oaks in row B are bigger and have lower branches than the oaks in row A. The ground around row B is covered with shoots of European elder (
We used a non-standard method to collect carabid beetles from the tree trunks: ‘wrapped paper bands’ (
Paper bands at several heights. Photo: Paul van Wielink
During more than six years, we monitored all 26 oaks from the base up to about 3 m height, 144 times at night. For more than two years within that period, the inspections were carried out nearly every week always on the same day (104 times). We started 1 to 6 hours after sunset; early in summer and in relatively late winter. Each visit took 35 to 90 minutes, depending on the number of beetles found. The trunks were illuminated by torch and we counted and noted the carabid beetles and their behaviour. For
In total, we observed 3069 specimens of 24 carabids beetle species (
Survey of species and numbers of
|
|
|
---|---|---|
18 | 2 | |
5 | - | |
4 | - | |
44 | 1 | |
8 | 1 | |
2 | 3 | |
- | 9 | |
|
13 | - |
1 | - | |
1 | - | |
1 | - | |
1 | 2 | |
- | 1 | |
1 | - | |
77 | 27 | |
1 | - | |
1 | - | |
9 | - | |
1 | - | |
41 | 2 | |
377 | 165 | |
38 | 4 | |
1654 | 64 | |
378 | 86 | |
10 | 4 | |
larvae undet | 8 | 4 |
Total number | 2694 | 375 |
Relative abundance ofCarabidaeduring weekly observations at night (
We observed six species of
On some trees we always saw more
The four most abundant species
Based on weekly observations at night on the lower 3 m of the trunks during two years we can present the phenology of
Phenology of
Phenology of
During the 144 nightly observations, we noted 63 copula in 1654
We never found larvae, neither on the trunks at night, nor in the bands. However we found two freshly emerged specimens of
Observing
Abdomen with sternites of
The common opinion seems to be that
The behaviour of biting algae and sphere building has not been recorded before in Europe.
During the nightly observations many copula of
We like to thank Henk Spijkers for his participation and creative suggestions at the beginning of the project.