Mysterious booklice in the Netherlands


This 2013 video says about itself:

Female Badonnelia titei feeding on a dead, dried maggot in a laboratory culture.

Translated from the Dutch entomologists of EIS Kenniscentrum Insecten:

18 January 2016 – Booklice are very little studied due to their small size (smaller than 5 millimeters). In recent years, the attention for these fascinating insects has increased, but it is not yet clear exactly which species occur in our country. For example, recently it was announced that Badonnelia titei lives in various places in our country. …

Badonnelia titei is an exotic species that most likely originates from South America, where they may originally have lived in caves. Oddly enough, the species has never been observed in the wild. It is found in Europe and the USA where it has been imported, in buildings, such as archives, museums and laboratories.

Insects in warm Dutch December


Male common darter dragonfly, photo by L. Tettenborn

Waarneming.nl in the Netherlands reports that in unusually warm December 2015, unusually many crickets and grasshoppers were seen: seven species.

Not only two damselfly species were seen, as usually: common winter damselfly and Siberian winter damselfly; but also (unusually late) adult common darter dragonflies.

Hornets wake up from hibernation, video


This video was made by Ab Wisselink, on 3 December 2015, near Mariënvelde village (Achterhoek region, the Netherlands). Mr Wisselink was photographing fungi. When he lifted an old piece of wood, he unintentionally woke up two hornets from their hibernation. They reacted rather sluggishly. After making the video, Ab Wisselink put the piece of wood back again.

New hoverfly species discovery in the Netherlands


Psilota exilistyla, photo by John Smit

Translated from John Smits in the Netherlands:

16 December 2015

The genus Psilota includes some small black hoverflies. They have long been overlooked, possibly because they do not look like very typical hoverflies. Since 1988, P. anthracina and P. atra have been observed in the Netherlands. There was suspicion that there was another species still. This was recently confirmed by DNA barcoding research by Naturalis. An individual of the Filosofendal near Beek and an individual of Velp were found to belong to P. exilistyla.

See also here.

Jumping wasp larvae, new research


This 2013 video is called Cocoons of Bathyplectes anurus.

From BioMed Central:

Cocooned wasp larvae jump to shaded areas to improve their survival

December 21, 2015

Jumping is not about fun and games for insect larvae. They must do it to survive. This manoeuvre is all about finding a shady spot to develop in, according to researchers from Kyushu University in Japan, who led research into the jumping behavior of a minute parasitic wasp, published in Springer’s journal The Science of Nature.

The use of jumping as a means of movement has only been observed in a few species of parasitic wasp larvae, suggesting that this behavior does not easily evolve. One such wasp is the three millimeter long Bathyplectes anurus. This parasite is used as a form of biological pest control against alfalfa weevil (Hypera postica), a destructive agricultural pest that attacks legumes.

Adult Bathyplectes anurus wasps lay their eggs in alfalfa weevil larvae. When the wasp larva develops, it crawls out from inside its host and promptly feeds on it. It then spends ten months in a self-spun cocoon inside the cocoon of the alfalfa weevil larva it has eaten, before developing into a pupa. During this time, the wasp larva performs whip-like twitches against the interior of the cocoon causing the entire structure to move approximately five centimeters at a time.

Lead researcher, Yoriko Saeki, and her team conducted a series of experiments on 100 Bathyplectes anurus larvae to understand if this behavior is a survival technique, and whether it comes at a cost to the insects. They examined the effects of different light intensities, temperatures, as well as levels of humidity under different laboratory and field conditions.

The Bathyplectes anurus cocoons exposed to light jumped nearly three times more often than those kept in darkness. Jumping activity increased during rapid temperature increases, and was 60 percent higher at conditions of low humidity. When the cocoons were allowed to jump freely in an area of gradient light going from dark to bright, more cocoons ended up in shady areas. Cocoons in the shady area were more likely to survive, compared to the cocoons left out in brighter light.

The cocoons jumped and moved about 83 percent more when they were placed near Japanese giant ants, known predators of this type of larvae, compared to when there were no danger elements in the vicinity. The frequency of movements decreased once the predators made direct contact with the cocoons.

The results suggest that the larvae respond to environmental stresses by jumping to more favorable habitats that allow them to develop unrestrictedly. The body mass of the individuals that jumped was lower compared to those that did not. The researchers suggest that this is because jumping behavior comes at a cost as it requires more energy use.

Further studies of cocoon structures and the physical mechanisms that allow for such jumping in related species will help entomologists to fully understand the evolution of this behavior.

Beautiful wasp for first time in the Netherlands


Chrysis equestris, photo by Maarten Jacobs

Translated from the Dutch EIS Kenniscentrum Insecten entomologists:

14 December 2015 – In the summer of 2015 a very beautiful coloured emerald wasp was found in the Weerterbos nature reserve [in Limburg province]. It took a long time before people knew which species the small animal was, but after consultation with emerald wasp experts it turned out to be Chrysis equestris. This is a new species for the Netherlands.

This is a parasitical wasp. Chrysis equestris females lay their eggs in nests of another wasp species, Discoelius zonalis.

See also here.

Rare European mole cricket, video


The European mole cricket in this video was found in an allotment garden in the Netherlands.

This species is rare there.

Gerard de Buck made this video.