Andricus-quercustozae_8 - a photo on Flickriver

Andricus quercustozae Bosc, syn.: Cynips argentea Hartig, Cynips kiefferi Cabrera, Cynips quercustojae Fabricius, Cynips rosenhaueri Hartig in Rosenhauer, Cynips tozae Kieffer
Cynipid gall wasp, Oak bud gall wasp DE: Kronengallwespe
Slo.: kroglasta hrastova šiškarica

Dat.: April 24. 2017
Lat.: 45.08283 Long.: 14.46628
Code: Bot_1049/2017_DSC7517

Habitat: a small opening in light broad-leaved trees and bushes; stony, nutrients pure grassland; flat terrain, calcareous, skeletal ground; predominantly sunny, dry place; elevation 165 m (540 feet), average precipitations ~1.000 mm/year, average temperature 13 - 14 deg C, submediterranean phytogeographical region.

Substratum: young Quercus pubescens trees.

Place: Next to the dirt road between villages Milohnići and Poljica, inland of the west part of island Krk, Adriatic Sea, Kvarner bay, Rijeka region, Croatia EC.

Comment: These galls are produced by gall-wasp (family Cynipidae) Andricus quercustozae. Heavily attacked young downy oaks (Quercus pubescens) were full of them. Generally, galling insects are not considered pests (some are even beneficial and used in biological control for weeds). However, heavy attack may harm young trees as it is evident from the pictures of one of them.

The plant galls develop after the female wasp insect lays egg(s) in a particular plant tissue. The inducement for the gall formation is largely unknown. Experts consider chemical, mechanical, and/or viral triggers. Anyway, insects demonstrate perfect DNA manipulation of host, which forces him to produce galls. Galls are shelters and food for larvae living in it. After complete metamorphosis larva transforms into adult wasp, which bores a small hole into the outer hard shell of the gall and leaves it.

But this is not necessarily the end of the story. Abandoned galls can be later populated by another inquiline species (another insect species that lives commensally in the abandoned galls). Since all galls on my pictures have distinct holes in their outer hard shell, through which grown up wasps abandoned their `homes`, the white larva inside internal shell (see picture 6a), must belong to another insect species and not to Andricus quercustozae. Which one cannot be determined from the pictures only.

Less lucky Andricus quercustozae larvae can be attacked by certain wasp species in spite of the fact that they reside inside their apparently safe homes. These parasitic wasps lay their eggs inside them from outside of the gall through their hard shell using their long, hardened egg-laying tube (ovipositor). In this case Andricus quercustozae larva serves as food for the new inhabitant of the gall. And yet, this is still not the end of the (worst case) story. There exist other insects, which recognize that galls are populated by parasitic insects and lay their eggs into them (hyperparasitoid species). So, a super-killer kills a killer, who broke in a foreign house and killed the house owner.

Ref.:
(1) Personal communication with Dr. Andreja Kavčič and dr. Nikica Ogris, Slovenia Forest Institute, Ljubljana
(2) www.invasive.org/browse/subthumb.cfm?sub=22149 slike (accessed Nov. 3. 2017)
(3) citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.334.499... (accessed Nov. 3. 2017)
(4) en.wikipedia.org/wiki/Gall_wasp (accessed Nov. 6. 2017)

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Taken on: April 24, 2017

Tags:

taxonomy:binomial=Andricus quercustozae

Cynips argentea

Cynips quercustojae

Cynips rosenhaueri

Cynips tozae

Cynipid gall wasp

Oak bud gall wasp

Kronengallwespe

kroglasta hrastova šiškarica

Andricus quercustozae

Cynips

argentea

kiefferi

quercustojae

rosenhaueri

tozae

gall wasp

hall

galls

Downy Oak

bud gall wasp

hrastova šiškarica

Andricus

quercustozae

wasp

oak

šiškarica

šiškarice

Cynipidae « less

Sets appears in: • Andricus quercustozae

Groups appears in: • Insects and butterflys • Las i łąka - Wald und Wiese more » • Encyclopedia of Life Images « less

Camera: Sony ILCE-6000, f/13.0, 1/40 sec, 69mm (=103mm), ISO 400 (more info) (hide info)

Camera:	Sony ILCE-6000
Lens:	E 16-70mm F4 ZA OSS
Aperture:	f/13.0
Exposure Time:	0.025 sec (1/40)
Focal Length:	69mm (35mm equivalent: 103mm)
ISO:	400
Exposure Bias:	-0.3 EV
Flash:	Off, Did not fire
Exposure Program:	Aperture-priority AE
Exposure Mode:	Auto
Metering Mode:	Center-weighted average
White Balance:	Auto
Color Space:	sRGB
Software:	Adobe Photoshop CS5.1 Windows
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